Merge remote-tracking branch 'origin/master'

.idea/modules.xml

@@ -65,6 +65,7 @@
       <module fileurl="file://$PROJECT_DIR$/plugins/devkit/jps-plugin/devkit-jps-plugin.iml" filepath="$PROJECT_DIR$/plugins/devkit/jps-plugin/devkit-jps-plugin.iml" group="plugins" />
       <module fileurl="file://$PROJECT_DIR$/platform/diff-api/diff-api.iml" filepath="$PROJECT_DIR$/platform/diff-api/diff-api.iml" group="platform" />
       <module fileurl="file://$PROJECT_DIR$/platform/diff-impl/diff-impl.iml" filepath="$PROJECT_DIR$/platform/diff-impl/diff-impl.iml" group="platform" />
+      <module fileurl="file://$PROJECT_DIR$/platform/diff-impl/diff-tests.iml" filepath="$PROJECT_DIR$/platform/diff-impl/diff-tests.iml" group="platform" />
       <module fileurl="file://$PROJECT_DIR$/xml/dom-impl/dom-impl.iml" filepath="$PROJECT_DIR$/xml/dom-impl/dom-impl.iml" group="xml" />
       <module fileurl="file://$PROJECT_DIR$/xml/dom-openapi/dom-openapi.iml" filepath="$PROJECT_DIR$/xml/dom-openapi/dom-openapi.iml" group="xml" />
       <module fileurl="file://$PROJECT_DIR$/xml/dom-tests/dom-tests.iml" filepath="$PROJECT_DIR$/xml/dom-tests/dom-tests.iml" group="xml" />

bin/scripts/unix/idea.sh

@@ -136,18 +136,22 @@ if [ -n "$@@product_uc@@_PROPERTIES" ]; then
   IDE_PROPERTIES_PROPERTY="-Didea.properties.file=$@@product_uc@@_PROPERTIES"
 fi
 
+vm_options_file="$IDE_BIN_HOME/@@vm_options@@$BITS.vmoptions"
+user_vm_options_file="$HOME/.@@system_selector@@/@@vm_options@@$BITS.vmoptions"
+if [ -r "$user_vm_options_file" ]; then
+  vm_options_file="$user_vm_options_file"
+fi
+if [ -n "$@@product_uc@@_VM_OPTIONS" ]; then
+  vm_options_file="$@@product_uc@@_VM_OPTIONS"
+fi
+
 VM_OPTIONS=""
-VM_OPTIONS_FILES_USED=""
-for vm_opts_file in "$IDE_BIN_HOME/@@vm_options@@$BITS.vmoptions" "$OS_SPECIFIC_BIN_DIR/@@vm_options@@$BITS.vmoptions" "$HOME/.@@system_selector@@/@@vm_options@@$BITS.vmoptions" "$@@product_uc@@_VM_OPTIONS"; do
-  if [ -r "$vm_opts_file" ]; then
-    VM_OPTIONS_DATA=`"$CAT" "$vm_opts_file" | "$GREP" -v "^#.*" | "$TR" '\n' ' '`
+if [ -r "$vm_options_file" ]; then
+    VM_OPTIONS_DATA=`"$CAT" "$vm_options_file" | "$GREP" -v "^#.*" | "$TR" '\n' ' '`
     VM_OPTIONS="$VM_OPTIONS $VM_OPTIONS_DATA"
-    if [ -n "$VM_OPTIONS_FILES_USED" ]; then
-      VM_OPTIONS_FILES_USED="$VM_OPTIONS_FILES_USED,"
-    fi
-    VM_OPTIONS_FILES_USED="$VM_OPTIONS_FILES_USED$vm_opts_file"
-  fi
-done
+else
+  message "Cannot find VM options file."
+fi
 
 IS_EAP="@@isEap@@"
 if [ "$IS_EAP" = "true" ]; then
@@ -172,7 +176,7 @@ LD_LIBRARY_PATH="$IDE_BIN_HOME:$LD_LIBRARY_PATH" "$JDK/jre/bin/java" \
   $AGENT \
   "-Xbootclasspath/a:$IDE_HOME/lib/boot.jar" \
   -classpath "$CLASSPATH" \
-  $VM_OPTIONS "-Djb.vmOptionsFile=$VM_OPTIONS_FILES_USED" \
+  $VM_OPTIONS "-Djb.vmOptionsFile=$vm_options_file" \
   "-XX:ErrorFile=$HOME/java_error_in_@@product_uc@@_%p.log" \
   -Djb.restart.code=88 -Didea.paths.selector=@@system_selector@@ \
   $IDE_PROPERTIES_PROPERTY \

java/execution/impl/testDiscovery/org/jetbrains/testme/instrumentation/Instrumenter.java

@@ -17,11 +17,11 @@
 package org.jetbrains.testme.instrumentation;
 
 import org.jetbrains.org.objectweb.asm.ClassVisitor;
-import org.jetbrains.org.objectweb.asm.Label;
 import org.jetbrains.org.objectweb.asm.MethodVisitor;
 import org.jetbrains.org.objectweb.asm.Opcodes;
 
 public class Instrumenter extends ClassVisitor {
+  private static final int ADDED_CODE_STACK_SIZE = 6;
   protected final ClassVisitor myClassVisitor;
   private final String myClassName;
   private final String myInternalClassName;
@@ -88,7 +88,7 @@ public class Instrumenter extends ClassVisitor {
       mv = new StaticBlockMethodVisitor(mv);
       mv.visitCode();
       mv.visitInsn(Opcodes.RETURN);
-      mv.visitMaxs(myMethodNames.length + 2, 1);
+      mv.visitMaxs(ADDED_CODE_STACK_SIZE, 0);
       mv.visitEnd();
     }
     super.visitEnd();
@@ -102,12 +102,11 @@ public class Instrumenter extends ClassVisitor {
     public void visitCode() {
       super.visitCode();
 
+      visitLdcInsn(myClassName);
       pushInstruction(this, myMethodNames.length);
       visitIntInsn(Opcodes.NEWARRAY, Opcodes.T_BOOLEAN);
-      visitFieldInsn(Opcodes.PUTSTATIC, myInternalClassName, METHODS_VISITED, METHODS_VISITED_CLASS);
 
       pushInstruction(this, myMethodNames.length);
-
       visitTypeInsn(Opcodes.ANEWARRAY, "java/lang/String");
 
       for(int i = 0; i < myMethodNames.length; ++i) {
@@ -117,28 +116,16 @@ public class Instrumenter extends ClassVisitor {
         visitInsn(Opcodes.AASTORE);
       }
 
-      visitVarInsn(Opcodes.ASTORE, 0);
+      visitMethodInsn(Opcodes.INVOKESTATIC, ProjectData.PROJECT_DATA_OWNER, "trace", "(Ljava/lang/String;[Z[Ljava/lang/String;)[Z", false);
+      visitFieldInsn(Opcodes.PUTSTATIC, myInternalClassName, METHODS_VISITED, METHODS_VISITED_CLASS);
 
-      Label startLabel = new Label();
-      visitLabel(startLabel);
-
-      visitLdcInsn(myClassName);
-      visitFieldInsn(Opcodes.GETSTATIC, myInternalClassName, METHODS_VISITED, METHODS_VISITED_CLASS);
-      visitVarInsn(Opcodes.ALOAD, 0);
-      visitMethodInsn(Opcodes.INVOKESTATIC, ProjectData.PROJECT_DATA_OWNER, "trace", "(Ljava/lang/String;[Z[Ljava/lang/String;)V", false);
-
-      Label endLabel = new Label();
-      visitLabel(endLabel);
-
-      visitLocalVariable("methodNames", "[Ljava/lang/String;", null, startLabel, endLabel, 0);
       // no return here
     }
 
     public void visitMaxs(int maxStack, int maxLocals) {
-      final int ourMaxStack = myMethodNames.length + 2;
-      final int ourMaxLocals = 1;
+      final int ourMaxStack = ADDED_CODE_STACK_SIZE;
 
-      super.visitMaxs(Math.max(ourMaxStack, maxStack), Math.max(ourMaxLocals, maxLocals));
+      super.visitMaxs(Math.max(ourMaxStack, maxStack), maxLocals);
     }
   }
 

java/execution/impl/testDiscovery/org/jetbrains/testme/instrumentation/ProjectData.java

@@ -17,42 +17,31 @@ public class ProjectData {
         myTraceDir = traceDir;
     }
 
-    private ConcurrentMap<String, Set<String>> myTrace;
     private final ConcurrentMap<String, boolean[]> myTrace2 = new ConcurrentHashMap<String, boolean[]>();
     private final ConcurrentMap<String, String[]> myTrace3 = new ConcurrentHashMap<String, String[]>();
 
     public static ProjectData getProjectData() {
         return ourData;
     }
-    
-    public static void trace(String className, String methodSignature) {
-        ourData.traceLines(className, methodSignature);
-    }
 
     // called from instrumented code during class's static init
-    public static void trace(String className, boolean[] methodFlags, String[] methodNames) {
-        ourData.traceLines(className, methodFlags, methodNames);
-    }
-    
-    public void traceLines(String className, String methodSignature) {
-        if (myTrace != null) {
-            Set<String> methods = myTrace.get(className);
-            if (methods == null) {
-                methods = new HashSet<String>();
-                Set<String> previousMethods = myTrace.putIfAbsent(className, methods);
-                if (previousMethods != null) methods = previousMethods;
-            }
-            synchronized (methods) {
-                methods.add(methodSignature);
-            }
-        }
+    public static boolean[] trace(String className, boolean[] methodFlags, String[] methodNames) {
+        return ourData.traceLines(className, methodFlags, methodNames);
     }
 
-    public synchronized void traceLines(String className, boolean[] methodFlags, String[] methodNames) {
+    private synchronized boolean[] traceLines(String className, boolean[] methodFlags, String[] methodNames) {
         //System.out.println("Registering " + className);
         assert methodFlags.length == methodNames.length;
-        myTrace2.put(className, methodFlags);
-        myTrace3.put(className, methodNames);
+        final boolean[] previousMethodFlags = myTrace2.putIfAbsent(className, methodFlags);
+
+        if (previousMethodFlags != null) {
+            assert previousMethodFlags.length == methodFlags.length;
+            final String[] previousMethodNames = myTrace3.get(className);
+            assert previousMethodNames != null && previousMethodNames.length == methodNames.length;
+        } else {
+            myTrace3.put(className, methodNames);
+        }
+        return previousMethodFlags != null ? previousMethodFlags : methodFlags;
     }
 
     private static final int STRING_LENGTH_THRESHOLD = 255;
@@ -163,22 +152,6 @@ public class ProjectData {
         catch (IOException e) {
            e.printStackTrace();
         }
-        finally {
-            myTrace = null;
-        }
-    }
-
-    private void saveOldTrace(DataOutputStream os) throws IOException {
-        os.writeInt(myTrace.size());
-        for (Iterator<String> it = myTrace.keySet().iterator(); it.hasNext();) {
-            final String classData = it.next();
-            os.writeUTF(classData);
-            final Set<String> methods = myTrace.get(classData);
-            os.writeInt(methods.size());
-            for (Iterator<String> iterator = methods.iterator(); iterator.hasNext(); ) {
-                os.writeUTF(iterator.next());
-            }
-        }
     }
 
     public synchronized void testStarted(final String name) {
@@ -190,8 +163,4 @@ public class ProjectData {
             }
         }
     }
-
-    private void clearOldTrace() {
-        myTrace = new ConcurrentHashMap<String, Set<String>>();
-    }
 }

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightMethodUtil.java

@@ -446,16 +446,30 @@ public class HighlightMethodUtil {
       final PsiMethod containerMethod = PsiTreeUtil.getParentOfType(methodCall, PsiMethod.class, true, PsiLambdaExpression.class);
       if (containerMethod != null) {
         final PsiMethod method = candidate.getElement();
-        final List<PsiType> list = ContainerUtil.map(method.getParameterList().getParameters(),
-                                                     new Function<PsiParameter, PsiType>() {
-                                                       @Override
-                                                       public PsiType fun(PsiParameter parameter) {
-                                                         return parameter.getType();
-                                                       }
-                                                     });
-        PsiType[] leftTypes = list.toArray(new PsiType[list.size()]);
+        final PsiType[] expressionTypes = methodCall.getArgumentList().getExpressionTypes();
+        final PsiParameter[] parameters = method.getParameterList().getParameters();
+        final int max = Math.max(parameters.length, expressionTypes.length);
+        PsiType[] leftTypes = PsiType.createArray(max);
+        PsiType[] rightTypes = PsiType.createArray(max);
+        for (int i = 0; i < max; i++) {
+          if (i < parameters.length) {
+            leftTypes[i] = parameters[i].getType();
+            rightTypes[i] = i < expressionTypes.length ? expressionTypes[i] : null;
+
+            if (leftTypes[i] instanceof PsiEllipsisType &&
+                !(max == expressionTypes.length && 
+                  expressionTypes[i] instanceof PsiArrayType && 
+                  expressionTypes[i].getArrayDimensions() == leftTypes[i].getArrayDimensions())) {
+              leftTypes[i] = ((PsiEllipsisType)leftTypes[i]).getComponentType();
+            }
+          }
+          else {
+            leftTypes[i] = null;
+            rightTypes[i] = i < expressionTypes.length ? expressionTypes[i] : null;
+          }
+        }
         final PsiSubstitutor substitutor = resolveHelper
-          .inferTypeArguments(method.getTypeParameters(), leftTypes, methodCall.getArgumentList().getExpressionTypes(),
+          .inferTypeArguments(method.getTypeParameters(), leftTypes, rightTypes,
                               PsiUtil.getLanguageLevel(methodCall));
         PsiType methodCallTypeByArgs = substitutor.substitute(methodCall.getType());
         //ensure type params are not included

java/java-impl/src/com/intellij/codeInsight/completion/JavaKeywordCompletion.java

@@ -227,7 +227,7 @@ public class JavaKeywordCompletion {
 
     if (psiElement().withText(";").withSuperParent(2, PsiIfStatement.class).accepts(prevLeaf) ||
         psiElement().withText("}").withSuperParent(3, PsiIfStatement.class).accepts(prevLeaf)) {
-      variant.consume(new OverrideableSpace(createKeyword(position, PsiKeyword.ELSE), TailTypes.SYNCHRONIZED_LPARENTH));
+      variant.consume(new OverrideableSpace(createKeyword(position, PsiKeyword.ELSE), TailType.HUMBLE_SPACE_BEFORE_WORD));
     }
 
     if (psiElement().withText("}").withParent(psiElement(PsiCodeBlock.class).withParent(or(psiElement(PsiTryStatement.class), psiElement(PsiCatchSection.class)))).accepts(prevLeaf)) {

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/DelegateWithDefaultParamValueIntentionAction.java

@@ -58,7 +58,7 @@ public class DelegateWithDefaultParamValueIntentionAction extends PsiElementBase
       if (declarationScope instanceof PsiMethod) {
         final PsiMethod method = (PsiMethod)declarationScope;
         final PsiClass containingClass = method.getContainingClass();
-        if (containingClass != null && (!containingClass.isInterface() || PsiUtil.isLanguageLevel7OrHigher(method))) {
+        if (containingClass != null && (!containingClass.isInterface() || PsiUtil.isLanguageLevel8OrHigher(method))) {
           if (containingClass.findMethodBySignature(generateMethodPrototype(method, parameter), false) != null) {
             return false;
           }

java/java-impl/src/com/intellij/codeInsight/javadoc/JavaDocInfoGenerator.java

@@ -971,13 +971,16 @@ public class JavaDocInfoGenerator {
 
     if (method instanceof PsiMethod) {
       PsiMethod psiMethod = (PsiMethod)method;
-      final PsiDocComment docComment = getDocComment(psiMethod);
-      final PsiDocTag[] localTags = docComment != null ? docComment.getTags() : PsiDocTag.EMPTY_ARRAY;
-      int parameterIndex = psiMethod.getParameterList().getParameterIndex(parameter);
-      final ParamInfo tagInfoProvider = findDocTag(localTags, parameterName, psiMethod, parameterLocator(parameterIndex));
+      PsiParameterList parameterList = psiMethod.getParameterList();
+      if (parameter.getParent() == parameterList) { // this can also be a parameter in foreach statement or in catch clause
+        final PsiDocComment docComment = getDocComment(psiMethod);
+        final PsiDocTag[] localTags = docComment != null ? docComment.getTags() : PsiDocTag.EMPTY_ARRAY;
+        int parameterIndex = parameterList.getParameterIndex(parameter);
+        final ParamInfo tagInfoProvider = findDocTag(localTags, parameterName, psiMethod, parameterLocator(parameterIndex));
 
-      if (tagInfoProvider != null) {
-        generateOneParameter(buffer, tagInfoProvider);
+        if (tagInfoProvider != null) {
+          generateOneParameter(buffer, tagInfoProvider);
+        }
       }
     }
 

java/java-psi-api/src/com/intellij/psi/util/ClassUtil.java

@@ -18,6 +18,7 @@ package com.intellij.psi.util;
 import com.intellij.openapi.util.Comparing;
 import com.intellij.psi.*;
 import com.intellij.psi.search.GlobalSearchScope;
+import gnu.trove.TObjectIntHashMap;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -64,11 +65,11 @@ public class ClassUtil {
       buf.append(qName);
     }
     else {
-      final PsiClass parentClass = getContainingClass(aClass);
+      final PsiClass parentClass = PsiTreeUtil.getContextOfType(aClass, PsiClass.class, true);
       if (parentClass != null) {
         formatClassName(parentClass, buf);
         buf.append("$");
-        buf.append(getNonQualifiedClassIdx(aClass));
+        buf.append(getNonQualifiedClassIdx(aClass, parentClass));
         final String name = aClass.getName();
         if (name != null) {
           buf.append(name);
@@ -77,42 +78,24 @@ public class ClassUtil {
     }
   }
 
-  @Nullable
-  private static PsiClass getContainingClass(@NotNull PsiClass aClass) {
-    PsiElement parent = aClass.getContext();
-    while (parent != null && !(parent instanceof PsiClass)) {
-      parent = parent.getContext();
-    }
-    return (PsiClass)parent;
-  }
-
-  public static int getNonQualifiedClassIdx(@NotNull final PsiClass psiClass) {
-    final int[] result = {-1};
-    final PsiClass containingClass = getContainingClass(psiClass);
-    if (containingClass != null) {
-      containingClass.accept(new JavaRecursiveElementVisitor() {
-        private int myCurrentIdx = 0;
-
+  private static int getNonQualifiedClassIdx(@NotNull final PsiClass psiClass, @NotNull final PsiClass containingClass) {
+    TObjectIntHashMap<PsiClass> indices =
+      CachedValuesManager.getCachedValue(containingClass, new CachedValueProvider<TObjectIntHashMap<PsiClass>>() {
+        @Nullable
         @Override
-        public void visitElement(PsiElement element) {
-          if (result[0] == -1) {
-            super.visitElement(element);
-          }
-        }
-
-        @Override
-        public void visitClass(PsiClass aClass) {
-          super.visitClass(aClass);
-          if (aClass.getQualifiedName() == null) {
-            myCurrentIdx++;
-            if (psiClass == aClass) {
-              result[0] = myCurrentIdx;
+        public Result<TObjectIntHashMap<PsiClass>> compute() {
+          final TObjectIntHashMap<PsiClass> map = new TObjectIntHashMap<PsiClass>();
+          int index = 0;
+          for (PsiClass aClass : SyntaxTraverser.psiTraverser().withRoot(containingClass).postOrderDfsTraversal().filter(PsiClass.class)) {
+            if (aClass.getQualifiedName() == null) {
+              map.put(aClass, ++index);
             }
           }
+          return Result.create(map, containingClass);
         }
       });
-    }
-    return result[0];
+
+    return indices.get(psiClass);
   }
 
   @SuppressWarnings("unused")

java/java-tests/testData/codeInsight/completion/keywords/elseAfterRBrace.java

@@ -1,6 +1,6 @@
 public class A {
   public void method() {
     if (true) { foo(); }
-    <caret>
+    el<caret>
   }
 }

java/java-tests/testData/codeInsight/completion/keywords/elseAfterRBrace_after.java

@@ -0,0 +1,6 @@
+public class A {
+  public void method() {
+    if (true) { foo(); }
+    else <caret>
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/afterInferFromVarArgs.java

@@ -0,0 +1,12 @@
+import java.util.List;
+
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "true"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  List<String> bar() {
+    return foo("");
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/afterInferFromVarArgs1.java

@@ -0,0 +1,12 @@
+import java.util.List;
+
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "true"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  List<String> bar() {
+    return foo("", "");
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/afterInferFromVarArgs3.java

@@ -0,0 +1,12 @@
+import java.util.List;
+
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "true"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  List<String> bar() {
+    return foo(new String[] {""});
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/beforeInferFromVarArgs.java

@@ -0,0 +1,10 @@
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "true"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  String bar() {
+    return fo<caret>o("");
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/beforeInferFromVarArgs1.java

@@ -0,0 +1,10 @@
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "true"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  String bar() {
+    return fo<caret>o("", "");
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/beforeInferFromVarArgs2.java

@@ -0,0 +1,10 @@
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "false"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  String bar() {
+    return fo<caret>o();
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/methodReturn/beforeInferFromVarArgs3.java

@@ -0,0 +1,10 @@
+// "Make 'bar' return 'java.util.List<java.lang.String>'" "true"
+public class Foo {
+  <T> java.util.List<T> foo(T... t) {
+    return null;
+  }
+
+  String bar() {
+    return fo<caret>o(new String[] {""});
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/completion/KeywordCompletionTest.java

@@ -76,8 +76,8 @@ public class KeywordCompletionTest extends LightCompletionTestCase {
   public void testMethodScope3() throws Exception { doTest(1, "final", "public", "static", "volatile", "abstract", "throws", "instanceof"); }
   public void testMethodScope4() throws Exception { doTest(6, "final", "try", "for", "while", "return", "throw"); }
   public void testMethodScope5() throws Exception { doTest(false); }
-  public void testElseAfterSemicolon() throws Exception { doTest(1, "else"); }
-  public void testElseAfterRBrace() throws Exception { doTest(1, "else"); }
+  public void testElseAfterSemicolon() { doTest(1, "else"); }
+  public void testElseAfterRBrace() { doTest(false); }
   public void testExtraBracketAfterFinally1() throws Exception { doTest(false); }
   public void testExtraBracketAfterFinally2() throws Exception { doTest(false); }
   public void testExtendsInCastTypeParameters() throws Exception { doTest(false); }
@@ -137,7 +137,7 @@ public class KeywordCompletionTest extends LightCompletionTestCase {
     assertEquals("this", myItems[1].getLookupString());
   }
 
-  private void doTest(boolean select) throws Exception {
+  private void doTest(boolean select) {
     configureByFile(BASE_PATH + "/" + getTestName(true) + ".java");
     if (select) {
       selectItem(myItems[0]);

java/java-tests/testSrc/com/intellij/codeInsight/daemon/quickFix/JavadocInspectionQuickFixTest.java

@@ -1,12 +1,17 @@
 /*
- * Copyright (c) 2000-2006 JetBrains s.r.o. All Rights Reserved.
- */
-
-/*
- * Created by IntelliJ IDEA.
- * User: Anna.Kozlova
- * Date: 06-Sep-2006
- * Time: 13:56:11
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 package com.intellij.codeInsight.daemon.quickFix;
 
@@ -27,11 +32,6 @@ public class JavadocInspectionQuickFixTest extends LightQuickFixParameterizedTes
     return new LocalInspectionTool[]{javaDocLocalInspection};
   }
 
-  @Override
-  protected void tearDown() throws Exception {
-    super.tearDown();
-  }
-
   public void test() throws Exception { doAllTests(); }
 
   @Override

java/java-tests/testSrc/com/intellij/unscramble/UnscrambleDialogTest.java

@@ -33,8 +33,12 @@ public class UnscrambleDialogTest extends JavaCodeInsightFixtureTestCase {
 
   @Override
   protected void tearDown() throws Exception {
-    Disposer.dispose(myContent);
-    super.tearDown();
+    try {
+      Disposer.dispose(myContent);
+    }
+    finally {
+      super.tearDown();
+    }
   }
 
   public void testStacktrace() throws Exception {
@@ -47,9 +51,9 @@ public class UnscrambleDialogTest extends JavaCodeInsightFixtureTestCase {
 
   public void testException() throws Exception {
     showText("java.lang.NullPointerException\n" +
-                                            "\tat com.intellij.psi.css.resolve.impl.XhtmlFileInfo.findOneStyleSheet(XhtmlFileInfo.java:291)\n" +
-                                            "\tat com.intellij.psi.css.resolve.impl.XhtmlFileInfo.getStylesheets(XhtmlFileInfo.java:174)\n" +
-                                            "\tat com.intellij.psi.css.resolve.impl.XhtmlFileInfo.initStylesheets(XhtmlFileInfo.java:119)");
+             "\tat com.intellij.psi.css.resolve.impl.XhtmlFileInfo.findOneStyleSheet(XhtmlFileInfo.java:291)\n" +
+             "\tat com.intellij.psi.css.resolve.impl.XhtmlFileInfo.getStylesheets(XhtmlFileInfo.java:174)\n" +
+             "\tat com.intellij.psi.css.resolve.impl.XhtmlFileInfo.initStylesheets(XhtmlFileInfo.java:119)");
     assertIcon("exception.png", myContent.getIcon());
     assertEquals("NPE", myContent.getDisplayName());
   }

java/testFramework/src/com/intellij/testFramework/ModuleTestCase.java

@@ -16,9 +16,7 @@
 package com.intellij.testFramework;
 
 import com.intellij.ide.highlighter.ModuleFileType;
-import com.intellij.openapi.application.AccessToken;
 import com.intellij.openapi.application.ApplicationManager;
-import com.intellij.openapi.application.WriteAction;
 import com.intellij.openapi.command.WriteCommandAction;
 import com.intellij.openapi.components.ComponentsPackage;
 import com.intellij.openapi.module.Module;
@@ -160,15 +158,13 @@ public abstract class ModuleTestCase extends IdeaTestCase {
   }
 
   protected final void loadModuleComponentState(@NotNull Module module, @NotNull Object component) {
-    AccessToken token = WriteAction.start();
+    ProjectEx project = (ProjectEx)myProject;
+    project.setOptimiseTestLoadSpeed(false);
     try {
-      ProjectEx project = (ProjectEx)myProject;
-      project.setOptimiseTestLoadSpeed(false);
       ComponentsPackage.getStateStore(module).initComponent(component, false);
-      project.setOptimiseTestLoadSpeed(true);
     }
     finally {
-      token.finish();
+      project.setOptimiseTestLoadSpeed(true);
     }
   }
 

lib/org/junit/runner/annotations.xml

@@ -0,0 +1,5 @@
+<root>
+  <item name='org.junit.runner.Description T getAnnotation(java.lang.Class&lt;T&gt;)'>
+    <annotation name='org.jetbrains.annotations.Nullable'/>
+  </item>
+</root>

native/MacLauncher/Launcher.m

@@ -375,23 +375,28 @@ NSString *getOverrideVMOptionsPath() {
 }
 
 NSArray *parseVMOptions() {
-    NSArray *files = @[getApplicationVMOptionsPath(),
-                       getUserVMOptionsPath(),
-                       getOverrideVMOptionsPath()];
+    NSString *vmOptionsFile = getApplicationVMOptionsPath();
+    NSString *userVMOptiosFile = getUserVMOptionsPath();
+    NSString *envVarVMOptiosFile = getOverrideVMOptionsPath();
+
+    if ([[NSFileManager defaultManager] fileExistsAtPath:userVMOptiosFile]) {
+      vmOptionsFile = userVMOptiosFile;
+    }
+    if ([[NSFileManager defaultManager] fileExistsAtPath:envVarVMOptiosFile]) {
+      vmOptionsFile = envVarVMOptiosFile;
+    }
 
     NSMutableArray *options = [NSMutableArray array];
     NSMutableArray *used = [NSMutableArray array];
 
-    for (NSString *file in files) {
-        NSLog(@"Processing VMOptions file at %@", file);
-        NSArray *contents = [VMOptionsReader readFile:file];
-        if (contents != nil) {
-            NSLog(@"Done");
-            [used addObject:file];
-            [options addObjectsFromArray:contents];
-        } else {
-            NSLog(@"No content found");
-        }
+    NSLog(@"Processing VMOptions file at %@", vmOptionsFile);
+    NSArray *contents = [VMOptionsReader readFile:vmOptionsFile];
+    if (contents != nil) {
+      NSLog(@"Done");
+      [used addObject:vmOptionsFile];
+      [options addObjectsFromArray:contents];
+    } else {
+      NSLog(@"No content found at %@ ", vmOptionsFile);
     }
     [options addObject:[NSString stringWithFormat:@"-Djb.vmOptionsFile=%@", [used componentsJoinedByString:@","]]];
 

native/WinLauncher/WinLauncher/WinLauncher.cpp

@@ -374,6 +374,29 @@ bool AddClassPathOptions(std::vector<std::string>& vmOptionLines)
   return true;
 }
 
+//return VMOptions from one of the files in the following order:
+//$<IDE-NAME>_VM_OPTIONS
+//$CONFIG_DIRECTORY/<ide-name>[64][.exe].vmoptions
+//bin/<ide-name>[64][.exe].vmoptions
+bool FindValidVMOptions(std::vector<std::wstring> files, std::wstring& used, std::vector<std::string>& vmOptionLines)
+{
+  if (files.size() != 0)
+  {
+    for (int i = 0; i < files.size(); i++)
+    {
+      if (GetFileAttributes(files[i].c_str()) != INVALID_FILE_ATTRIBUTES)
+      {
+        if (LoadVMOptionsFile(files[i].c_str(), vmOptionLines))
+        {
+          used += (used.size() ? L"," : L"") + files[i];
+          return true;
+        }
+      }
+    }
+  }
+  return false;
+}
+
 void AddPredefinedVMOptions(std::vector<std::string>& vmOptionLines)
 {
   std::string vmOptions = LoadStdString(IDS_VM_OPTIONS);
@@ -403,8 +426,13 @@ bool LoadVMOptions()
   GetModuleFileName(NULL, buffer, _MAX_PATH);
   std::wstring module(buffer);
 
-  files.push_back(module + L".vmoptions");
-
+  if (LoadString(hInst, IDS_VM_OPTIONS_ENV_VAR, buffer, _MAX_PATH))
+  {
+    if (GetEnvironmentVariableW(buffer, copy, _MAX_PATH)) {
+      ExpandEnvironmentStrings(copy, buffer, _MAX_PATH);
+      files.push_back(std::wstring(buffer));
+    }
+  }
 
   if (LoadString(hInst, IDS_VM_OPTIONS_PATH, buffer, _MAX_PATH))
   {
@@ -413,33 +441,17 @@ bool LoadVMOptions()
     files.push_back(selector + module.substr(module.find_last_of('\\')) + L".vmoptions");
   }
 
-  if (LoadString(hInst, IDS_VM_OPTIONS_ENV_VAR, buffer, _MAX_PATH))
-  {
-    if (GetEnvironmentVariableW(buffer, copy, _MAX_PATH)) {
-    ExpandEnvironmentStrings(copy, buffer, _MAX_PATH);
-    files.push_back(std::wstring(buffer));
-    }
-  }
+  files.push_back(module + L".vmoptions");
+  std::wstring used;
+  std::vector<std::string> vmOptionLines;
 
-  if (files.size() == 0) {
+  if (!FindValidVMOptions(files, used, vmOptionLines))
+  {
     std::string error = LoadStdString(IDS_ERROR_LAUNCHING_APP);
     MessageBoxA(NULL, "Cannot find VM options file", error.c_str(), MB_OK);
     return false;
   }
 
-  std::wstring used;
-  std::vector<std::string> vmOptionLines;
-  for (int i = 0; i < files.size(); i++)
-  {
-    if (GetFileAttributes(files[i].c_str()) != INVALID_FILE_ATTRIBUTES)
-    {
-      if (LoadVMOptionsFile(files[i].c_str(), vmOptionLines))
-      {
-        used += (used.size() ? L"," : L"") + files[i];
-      }
-    }
-  }
-
   vmOptionLines.push_back(std::string("-Djb.vmOptions=") + EncodeWideACP(used));
 
   if (!AddClassPathOptions(vmOptionLines)) return false;

platform/analysis-impl/src/com/intellij/codeInspection/reference/RefEntityImpl.java

@@ -45,7 +45,7 @@ abstract class RefEntityImpl implements RefEntity {
 
   RefEntityImpl(@NotNull String name, @NotNull RefManager manager) {
     myManager = (RefManagerImpl)manager;
-    myName = name;
+    myName = myManager.internName(name);
   }
 
   @NotNull

platform/analysis-impl/src/com/intellij/codeInspection/reference/RefManagerImpl.java

@@ -54,6 +54,7 @@ import com.intellij.psi.impl.light.LightElement;
 import com.intellij.util.ConcurrencyUtil;
 import com.intellij.util.Consumer;
 import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.containers.StringInterner;
 import gnu.trove.THashMap;
 import org.jdom.Element;
 import org.jetbrains.annotations.NotNull;
@@ -85,6 +86,7 @@ public class RefManagerImpl extends RefManager {
 
   private final Map<Key, RefManagerExtension> myExtensions = new THashMap<Key, RefManagerExtension>();
   private final Map<Language, RefManagerExtension> myLanguageExtensions = new HashMap<Language, RefManagerExtension>();
+  private final StringInterner myNameInterner = new StringInterner();
 
   public RefManagerImpl(@NotNull Project project, @Nullable AnalysisScope scope, @NotNull GlobalInspectionContext context) {
     myProject = project;
@@ -106,6 +108,12 @@ public class RefManagerImpl extends RefManager {
     }
   }
 
+  public String internName(@NotNull String name) {
+    synchronized (myNameInterner) {
+      return myNameInterner.intern(name);
+    }
+  }
+
   @NotNull
   public GlobalInspectionContext getContext() {
     return myContext;

platform/configuration-store-impl/src/ApplicationStoreImpl.kt

@@ -76,6 +76,4 @@ class ApplicationStoreImpl(private val application: ApplicationImpl, pathMacroMa
       }
     }
   }
-
-  override fun getMessageBus() = application.getMessageBus()
 }

platform/configuration-store-impl/src/ComponentStoreImpl.kt

@@ -19,6 +19,7 @@ import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.application.PathManager
 import com.intellij.openapi.application.WriteAction
 import com.intellij.openapi.application.ex.DecodeDefaultsUtil
+import com.intellij.openapi.application.runBatchUpdate
 import com.intellij.openapi.components.*
 import com.intellij.openapi.components.StateStorage.SaveSession
 import com.intellij.openapi.components.StateStorageChooserEx.Resolution
@@ -53,6 +54,9 @@ import java.util.concurrent.CopyOnWriteArrayList
 
 private val LOG = Logger.getInstance(javaClass<ComponentStoreImpl>())
 
+/**
+ * <b>Note:</b> this class is used in upsource, please notify upsource team in case you change its API.
+ */
 public abstract class ComponentStoreImpl : IComponentStore {
   private val myComponents = Collections.synchronizedMap(THashMap<String, Any>())
   private val mySettingsSavingComponents = CopyOnWriteArrayList<SettingsSavingComponent>()
@@ -346,8 +350,10 @@ public abstract class ComponentStoreImpl : IComponentStore {
     return notReloadableComponents ?: emptySet<String>()
   }
 
-  override final fun reloadStates(componentNames: MutableSet<String>) {
-    reinitComponents(componentNames)
+  override final fun reloadStates(componentNames: MutableSet<String>, messageBus: MessageBus) {
+    runBatchUpdate(messageBus) {
+      reinitComponents(componentNames)
+    }
   }
 
   override final fun reloadState(componentClass: Class<out PersistentStateComponent<*>>) {
@@ -370,8 +376,6 @@ public abstract class ComponentStoreImpl : IComponentStore {
     }
   }
 
-  protected abstract fun getMessageBus(): MessageBus
-
   /**
    * null if reloaded
    * empty list if nothing to reload
@@ -404,19 +408,15 @@ public abstract class ComponentStoreImpl : IComponentStore {
   }
 
   // used in settings repository plugin
+  /**
+   * You must call it in batch mode (use runBatchUpdate)
+   */
   public fun reinitComponents(componentNames: Set<String>, changedStorages: Set<StateStorage> = emptySet(), notReloadableComponents: Collection<String> = emptySet()) {
-    val messageBus = getMessageBus()
-    messageBus.syncPublisher(BatchUpdateListener.TOPIC).onBatchUpdateStarted()
-    try {
-      for (componentName in componentNames) {
-        if (!notReloadableComponents.contains(componentName)) {
-          reloadState(componentName, changedStorages)
-        }
+    for (componentName in componentNames) {
+      if (!notReloadableComponents.contains(componentName)) {
+        reloadState(componentName, changedStorages)
       }
     }
-    finally {
-      messageBus.syncPublisher(BatchUpdateListener.TOPIC).onBatchUpdateFinished()
-    }
   }
 
   companion object {

platform/configuration-store-impl/src/DefaultProjectStoreImpl.kt

@@ -85,9 +85,7 @@ class DefaultProjectStoreImpl(override val project: ProjectImpl, private val pat
 
   // don't want to optimize and use already loaded data - it will add unnecessary complexity and implementation-lock (currently we store loaded archived state in memory, but later implementation can be changed)
   fun getStateCopy() = storage.loadLocalData()
-
-  override fun getMessageBus() = project.getMessageBus()
-
+  
   override final fun getPathMacroManagerForDefaults() = pathMacroManager
 
   override fun selectDefaultStorages(storages: Array<Storage>, operation: StateStorageOperation) = selectDefaultStorages(storages, operation, StorageScheme.DEFAULT)

platform/configuration-store-impl/src/ModuleStoreImpl.kt

@@ -18,22 +18,18 @@ package com.intellij.configurationStore
 import com.intellij.openapi.components.PathMacroManager
 import com.intellij.openapi.components.StoragePathMacros
 import com.intellij.openapi.module.Module
-import com.intellij.openapi.project.Project
 import com.intellij.openapi.project.ex.ProjectEx
 
-class ModuleStoreImpl(private val module: Module, private val pathMacroManager: PathMacroManager) : ComponentStoreImpl() {
-  override val storageManager = ModuleStateStorageManager(pathMacroManager.createTrackingSubstitutor(), module)
+class ModuleStoreImpl(module: Module, private val pathMacroManager: PathMacroManager) : ComponentStoreImpl() {
+  override val project = module.getProject()
 
-  override val project: Project?
-    get() = module.getProject()
+  override val storageManager = ModuleStateStorageManager(pathMacroManager.createTrackingSubstitutor(), module)
 
   override fun setPath(path: String) {
     storageManager.addMacro(StoragePathMacros.MODULE_FILE, path)
   }
 
-  override fun optimizeTestLoading() = (module.getProject() as ProjectEx).isOptimiseTestLoadSpeed()
-
-  override fun getMessageBus() = module.getMessageBus()
+  override fun optimizeTestLoading() = (project as ProjectEx).isOptimiseTestLoadSpeed()
 
   override final fun getPathMacroManagerForDefaults() = pathMacroManager
 }

platform/configuration-store-impl/src/ProjectStoreImpl.kt

@@ -247,8 +247,6 @@ open class ProjectStoreImpl(override val project: ProjectImpl, private val pathM
   protected open fun beforeSave(readonlyFiles: List<Pair<SaveSession, VirtualFile>>) {
   }
 
-  override fun getMessageBus() = project.getMessageBus()
-
   override fun <T> getStorageSpecs(component: PersistentStateComponent<T>, stateSpec: State, operation: StateStorageOperation): Array<Storage> {
     // if we create project from default, component state written not to own storage file, but to project file,
     // we don't have time to fix it properly, so, ancient hack restored.

platform/configuration-store-impl/src/StateStorageManagerImpl.kt

@@ -46,6 +46,8 @@ import kotlin.reflect.jvm.java
 
 /**
  * If componentManager not specified, storage will not add file tracker (see VirtualFileTracker)
+ * <p/>
+ * <b>Note:</b> this class is used in upsource, please notify upsource team in case you change its API.
  */
 open class StateStorageManagerImpl(private val rootTagName: String,
                                    private val pathMacroSubstitutor: TrackingPathMacroSubstitutor? = null,

platform/configuration-store-impl/src/StoreAwareProjectManager.kt

@@ -18,8 +18,8 @@ package com.intellij.configurationStore
 import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.application.ApplicationNamesInfo
 import com.intellij.openapi.application.ModalityState
-import com.intellij.openapi.application.WriteAction
 import com.intellij.openapi.application.ex.ApplicationManagerEx
+import com.intellij.openapi.application.runBatchUpdate
 import com.intellij.openapi.components.ComponentManager
 import com.intellij.openapi.components.StateStorage
 import com.intellij.openapi.components.impl.stores.*
@@ -65,10 +65,12 @@ class StoreAwareProjectManager(virtualFileManager: VirtualFileManager, progressM
         val changes = CHANGED_FILES_KEY.get(project) ?: continue
         CHANGED_FILES_KEY.set(project, null)
         if (!changes.isEmpty()) {
-          for ((store, storages) in changes.entrySet()) {
-            @suppress("UNCHECKED_CAST")
-            if (reloadStore(storages as Set<StateStorage>, store, false) == ReloadComponentStoreStatus.RESTART_AGREED) {
-              projectsToReload.add(project)
+          runBatchUpdate(project.getMessageBus()) {
+            for ((store, storages) in changes.entrySet()) {
+              @suppress("UNCHECKED_CAST")
+              if (reloadStore(storages as Set<StateStorage>, store, false) == ReloadComponentStoreStatus.RESTART_AGREED) {
+                projectsToReload.add(project)
+              }
             }
           }
         }
@@ -216,7 +218,6 @@ private fun reloadStore(changedStorages: Set<StateStorage>, store: ComponentStor
   val notReloadableComponents: Collection<String>?
   var willBeReloaded = false
   try {
-    val token = WriteAction.start()
     try {
       notReloadableComponents = store.reload(changedStorages)
     }
@@ -225,9 +226,6 @@ private fun reloadStore(changedStorages: Set<StateStorage>, store: ComponentStor
       Messages.showWarningDialog(ProjectBundle.message("project.reload.failed", e.getMessage()), ProjectBundle.message("project.reload.failed.title"))
       return ReloadComponentStoreStatus.ERROR
     }
-    finally {
-      token.finish()
-    }
 
     if (notReloadableComponents == null || notReloadableComponents.isEmpty()) {
       return ReloadComponentStoreStatus.SUCCESS

platform/configuration-store-impl/testSrc/ApplicationStoreTest.kt

@@ -16,7 +16,6 @@
 package com.intellij.configurationStore
 
 import com.intellij.application.options.PathMacrosImpl
-import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.application.runWriteAction
 import com.intellij.openapi.components.*
 import com.intellij.openapi.components.impl.stores.StreamProvider
@@ -149,8 +148,6 @@ class ApplicationStoreTest {
     override fun setPath(path: String) {
       storageManager.addMacro(StoragePathMacros.APP_CONFIG, path)
     }
-
-    override fun getMessageBus() = ApplicationManager.getApplication().getMessageBus()
   }
 
   abstract class Foo {

platform/configuration-store-impl/testSrc/ModuleStoreTest.kt

@@ -1,23 +1,30 @@
 package com.intellij.configurationStore
 
 import com.intellij.openapi.application.runWriteAction
+import com.intellij.openapi.components.StoragePathMacros
+import com.intellij.openapi.components.impl.stores.BatchUpdateListener
+import com.intellij.openapi.components.stateStore
 import com.intellij.openapi.module.Module
 import com.intellij.openapi.module.ModuleManager
 import com.intellij.openapi.module.ModuleTypeId
-import com.intellij.openapi.project.Project
-import com.intellij.openapi.project.ex.ProjectEx
+import com.intellij.openapi.project.ProjectManager
 import com.intellij.openapi.roots.ModuleRootManager
 import com.intellij.openapi.roots.ModuleRootModificationUtil
 import com.intellij.openapi.roots.impl.storage.ClasspathStorage
+import com.intellij.openapi.vfs.LocalFileSystem
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.testFramework.*
+import gnu.trove.TObjectIntHashMap
 import org.assertj.core.api.Assertions.assertThat
 import org.junit.ClassRule
 import org.junit.Rule
 import org.junit.Test
 import java.nio.file.Path
+import java.nio.file.Paths
 
-@RunsInEdt class ModuleStoreTest {
+@RunsInEdt
+@RunsInActiveStoreMode
+class ModuleStoreTest {
   companion object {
      ClassRule val projectRule = ProjectRule()
 
@@ -39,7 +46,7 @@ import java.nio.file.Path
 
   private val tempDirManager = TemporaryDirectory()
 
-  private val ruleChain = RuleChain(tempDirManager, EdtRule())
+  private val ruleChain = RuleChain(tempDirManager, EdtRule(), ActiveStoreRule(projectRule), DisposeModulesRule(projectRule))
 
   public Rule fun getChain(): RuleChain = ruleChain
 
@@ -49,53 +56,107 @@ import java.nio.file.Path
         "<module type=\"JAVA_MODULE\" foo=\"bar\" version=\"4\" />")
     }
 
-    projectRule.project.runInStoreLoadMode {
-      moduleFile.loadModule().useAndDispose {
-        assertThat(getOptionValue("foo")).isEqualTo("bar")
+    moduleFile.loadModule().useAndDispose {
+      assertThat(getOptionValue("foo")).isEqualTo("bar")
 
-        setOption("foo", "not bar")
-        saveStore()
-      }
+      setOption("foo", "not bar")
+      saveStore()
+    }
 
-      moduleFile.loadModule().useAndDispose {
-        assertThat(getOptionValue("foo")).isEqualTo("not bar")
+    moduleFile.loadModule().useAndDispose {
+      assertThat(getOptionValue("foo")).isEqualTo("not bar")
 
-        setOption("foo", "not bar")
-        saveStore()
-      }
+      setOption("foo", "not bar")
+      saveStore()
     }
   }
 
   @Test fun `must be empty if classpath storage`() {
     // we must not use VFS here, file must not be created
     val moduleFile = tempDirManager.newPath("module").resolve("test.iml")
-    projectRule.project.runInStoreLoadMode {
-      moduleFile.createModule().useAndDispose {
-        ModuleRootModificationUtil.addContentRoot(this, moduleFile.parentSystemIndependentPath)
-        saveStore()
-        assertThat(moduleFile).isRegularFile()
-        assertThat(moduleFile.readText()).startsWith("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<module type=\"JAVA_MODULE\" version=\"4\">")
+    moduleFile.createModule().useAndDispose {
+      ModuleRootModificationUtil.addContentRoot(this, moduleFile.parentSystemIndependentPath)
+      saveStore()
+      assertThat(moduleFile).isRegularFile()
+      assertThat(moduleFile.readText()).startsWith("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<module type=\"JAVA_MODULE\" version=\"4\">")
 
-        ClasspathStorage.setStorageType(ModuleRootManager.getInstance(this), "eclipse")
-        saveStore()
-        assertThat(moduleFile).hasContent("""<?xml version="1.0" encoding="UTF-8"?>
+      ClasspathStorage.setStorageType(ModuleRootManager.getInstance(this), "eclipse")
+      saveStore()
+      assertThat(moduleFile).hasContent("""<?xml version="1.0" encoding="UTF-8"?>
 <module classpath="eclipse" classpath-dir="$MODULE_DIR" type="JAVA_MODULE" version="4" />""")
+    }
+  }
+
+  @Test fun `one batch update session if several modules changed`() {
+    val nameToCount = TObjectIntHashMap<String>()
+    val root = tempDirManager.newPath()
+
+    fun Module.addContentRoot() {
+      val moduleName = getName()
+      var batchUpdateCount = 0
+      nameToCount.put(moduleName, batchUpdateCount)
+
+      getMessageBus().connect().subscribe(BatchUpdateListener.TOPIC, object : BatchUpdateListener {
+        override fun onBatchUpdateStarted() {
+          nameToCount.put(moduleName, ++batchUpdateCount)
+        }
+
+        override fun onBatchUpdateFinished() {
+        }
+      })
+
+      //
+      ModuleRootModificationUtil.addContentRoot(this, root.resolve(moduleName).systemIndependentPath)
+      assertThat(contentRootUrls).hasSize(1)
+      saveStore()
+    }
+
+    fun Module.removeContentRoot() {
+      val modulePath = stateStore.getStateStorageManager().expandMacros(StoragePathMacros.MODULE_FILE)
+      val moduleFile = Paths.get(modulePath)
+      assertThat(moduleFile).isRegularFile()
+
+      val virtualFile = LocalFileSystem.getInstance().findFileByPath(modulePath)!!
+      val newData = moduleFile.readText().replace("<content url=\"file://\$MODULE_DIR$/${getName()}\" />\n", "").toByteArray()
+      runWriteAction {
+        virtualFile.setBinaryContent(newData)
       }
     }
+
+    fun Module.assertChangesApplied() {
+      assertThat(contentRootUrls).isEmpty()
+    }
+
+    val m1 = root.resolve("m1.iml").createModule()
+    val m2 = root.resolve("m2.iml").createModule()
+
+    var projectBatchUpdateCount = 0
+    projectRule.project.getMessageBus().connect(m1).subscribe(BatchUpdateListener.TOPIC, object : BatchUpdateListener {
+      override fun onBatchUpdateStarted() {
+        nameToCount.put("p", ++projectBatchUpdateCount)
+      }
+
+      override fun onBatchUpdateFinished() {
+      }
+    })
+
+    m1.addContentRoot()
+    m2.addContentRoot()
+
+    m1.removeContentRoot()
+    m2.removeContentRoot()
+
+    (ProjectManager.getInstance() as StoreAwareProjectManager).flushChangedAlarm()
+
+    m1.assertChangesApplied()
+    m2.assertChangesApplied()
+
+    assertThat(nameToCount.size()).isEqualTo(3)
+    assertThat(nameToCount.get("p")).isEqualTo(1)
+    assertThat(nameToCount.get("m1")).isEqualTo(1)
+    assertThat(nameToCount.get("m1")).isEqualTo(1)
   }
 }
 
-inline fun <T> Project.runInStoreLoadMode(task: () -> T): T {
-  val isModeDisabled = (this as ProjectEx).isOptimiseTestLoadSpeed()
-  if (isModeDisabled) {
-    setOptimiseTestLoadSpeed(false)
-  }
-  try {
-    return task()
-  }
-  finally {
-    if (isModeDisabled) {
-      setOptimiseTestLoadSpeed(true)
-    }
-  }
-}
+val Module.contentRootUrls: Array<String>
+  get() = ModuleRootManager.getInstance(this).getContentRootUrls()

platform/core-impl/src/com/intellij/ide/plugins/PluginManagerCore.java

@@ -486,23 +486,48 @@ public class PluginManagerCore {
     return 0;
   }
 
-  @NotNull
   private static Collection<URL> getClassLoaderUrls() {
+    Collection<URL> urls = null;
     final ClassLoader classLoader = PluginManagerCore.class.getClassLoader();
     final Class<? extends ClassLoader> aClass = classLoader.getClass();
     try {
-      @SuppressWarnings("unchecked") List<URL> urls = (List<URL>)aClass.getMethod("getUrls").invoke(classLoader);
-      return urls;
+      //noinspection unchecked
+      urls = (List<URL>)aClass.getMethod("getUrls").invoke(classLoader);
     }
     catch (IllegalAccessException ignored) { }
     catch (InvocationTargetException ignored) { }
     catch (NoSuchMethodException ignored) { }
 
-    if (classLoader instanceof URLClassLoader) {
-      return Arrays.asList(((URLClassLoader)classLoader).getURLs());
+    if (urls == null && classLoader instanceof URLClassLoader) {
+      urls = Arrays.asList(((URLClassLoader)classLoader).getURLs());
     }
 
-    return Collections.emptyList();
+    return urls == null ? Collections.<URL>emptyList() : getClassLoaderUrls(urls);
+  }
+
+  public static Collection<URL> getClassLoaderUrls(Collection<URL> urls) {
+    List<URL> additionalRefs = new ArrayList<URL>();
+    for (URL url : urls) {
+      if ("file".equals(url.getProtocol())) {
+        File file = new File(decodeUrl(url.getFile()));
+        final String[] referencedJars = ClassPath.loadManifestClasspath(file);
+        if (referencedJars != null) {
+          for (String referencedJar : referencedJars) {
+            try {
+              additionalRefs.add(new URL(referencedJar));
+            }
+            catch (Exception ignore) {}
+          }
+        }
+      }
+    }
+
+    if (!additionalRefs.isEmpty()) {
+      Collection<URL> result = new ArrayList<URL>(urls);
+      result.addAll(additionalRefs);
+      return result;
+    }
+    return urls;
   }
 
   private static void prepareLoadingPluginsErrorMessage(@NotNull List<String> errors) {
@@ -907,21 +932,6 @@ public class PluginManagerCore {
           if (progress != null && !pluginDescriptor.getName().equals(SPECIAL_IDEA_PLUGIN)) {
             progress.showProgress("Plugin loaded: " + pluginDescriptor.getName(), PLUGINS_PROGRESS_MAX_VALUE * (float)i / urls.size());
           }
-          continue;
-        }
-
-        final String[] referencedJars = ClassPath.loadManifestClasspath(file);
-        if (referencedJars != null) {
-          for (String referencedJar : referencedJars) {
-            final File referencedFile;
-            try {
-              referencedFile = new File(new URI(referencedJar));
-            }
-            catch (Exception e) {
-              continue;
-            }
-            loadDescriptorFromClassPath(referencedFile, result, platformPrefix);
-          }
         }
       }
     }

platform/diff-api/src/com/intellij/diff/DiffContentFactory.java

@@ -18,6 +18,7 @@ package com.intellij.diff;
 import com.intellij.diff.contents.DiffContent;
 import com.intellij.diff.contents.DocumentContent;
 import com.intellij.diff.contents.EmptyContent;
+import com.intellij.diff.contents.FileContent;
 import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.fileTypes.FileType;
@@ -64,6 +65,9 @@ public abstract class DiffContentFactory {
   @Nullable
   public abstract DocumentContent createDocument(@Nullable Project project, @NotNull VirtualFile file);
 
+  @Nullable
+  public abstract FileContent createFile(@Nullable Project project, @NotNull VirtualFile file);
+
   @NotNull
   public abstract DiffContent createClipboardContent();
 

platform/diff-api/src/com/intellij/diff/DiffDialogHints.java

@@ -16,9 +16,11 @@
 package com.intellij.diff;
 
 import com.intellij.openapi.ui.WindowWrapper;
+import com.intellij.openapi.util.BooleanGetter;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import javax.swing.*;
 import java.awt.*;
 
 public class DiffDialogHints {
@@ -32,7 +34,9 @@ public class DiffDialogHints {
   //
 
   @Nullable private final WindowWrapper.Mode myMode;
-  @Nullable private final Component myParent;
+  @Nullable private Component myParent;
+  @Nullable private BooleanGetter myOkAction;
+  @Nullable private BooleanGetter myCancelAction;
 
   public DiffDialogHints(@Nullable WindowWrapper.Mode mode) {
     this(mode, null);
@@ -43,6 +47,18 @@ public class DiffDialogHints {
     myParent = parent;
   }
 
+  public void setParent(@Nullable Component value) {
+    myParent = value;
+  }
+
+  public void setOkAction(@Nullable BooleanGetter value) {
+    myOkAction = value;
+  }
+
+  public void setCancelAction(@Nullable BooleanGetter value) {
+    myCancelAction = value;
+  }
+
   //
   // Getters
   //
@@ -56,4 +72,14 @@ public class DiffDialogHints {
   public Component getParent() {
     return myParent;
   }
+
+  @Nullable
+  public BooleanGetter getOkAction() {
+    return myOkAction;
+  }
+
+  @Nullable
+  public BooleanGetter getCancelAction() {
+    return myCancelAction;
+  }
 }

platform/diff-api/src/com/intellij/diff/DiffManager.java

@@ -16,6 +16,7 @@
 package com.intellij.diff;
 
 import com.intellij.diff.chains.DiffRequestChain;
+import com.intellij.diff.merge.MergeRequest;
 import com.intellij.diff.requests.DiffRequest;
 import com.intellij.openapi.Disposable;
 import com.intellij.openapi.components.ServiceManager;
@@ -47,4 +48,7 @@ public abstract class DiffManager {
 
   @NotNull
   public abstract DiffRequestPanel createRequestPanel(@Nullable Project project, @NotNull Disposable parent, @Nullable Window window);
+
+  @CalledInAwt
+  public abstract void showMerge(@Nullable Project project, @NotNull MergeRequest request);
 }

platform/diff-api/src/com/intellij/diff/DiffManagerEx.java

@@ -16,6 +16,8 @@
 package com.intellij.diff;
 
 import com.intellij.diff.chains.DiffRequestChain;
+import com.intellij.diff.merge.MergeRequest;
+import com.intellij.diff.merge.MergeTool;
 import com.intellij.diff.requests.DiffRequest;
 import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.project.Project;
@@ -45,6 +47,12 @@ public abstract class DiffManagerEx extends DiffManager {
   @CalledInAwt
   public abstract void showDiffBuiltin(@Nullable Project project, @NotNull DiffRequestChain requests, @NotNull DiffDialogHints hints);
 
+  @CalledInAwt
+  public abstract void showMergeBuiltin(@Nullable Project project, @NotNull MergeRequest request);
+
   @NotNull
   public abstract List<DiffTool> getDiffTools();
+
+  @NotNull
+  public abstract List<MergeTool> getMergeTools();
 }

platform/diff-api/src/com/intellij/diff/DiffRequestFactory.java

@@ -15,13 +15,21 @@
  */
 package com.intellij.diff;
 
+import com.intellij.diff.merge.MergeRequest;
+import com.intellij.diff.merge.MergeResult;
+import com.intellij.diff.merge.TextMergeRequest;
 import com.intellij.diff.requests.ContentDiffRequest;
 import com.intellij.openapi.components.ServiceManager;
+import com.intellij.openapi.editor.Document;
+import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.util.Consumer;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.List;
+
 /*
  * Use ProgressManager.executeProcessUnderProgress() to pass modality state if needed
  */
@@ -31,12 +39,19 @@ public abstract class DiffRequestFactory {
     return ServiceManager.getService(DiffRequestFactory.class);
   }
 
+  //
+  // Diff
+  //
+
   @NotNull
   public abstract ContentDiffRequest createFromFiles(@Nullable Project project, @NotNull VirtualFile file1, @NotNull VirtualFile file2);
 
   @NotNull
   public abstract ContentDiffRequest createClipboardVsValue(@NotNull String value);
 
+  //
+  // Titles
+  //
 
   @NotNull
   public abstract String getContentTitle(@NotNull VirtualFile file);
@@ -46,4 +61,63 @@ public abstract class DiffRequestFactory {
 
   @NotNull
   public abstract String getTitle(@NotNull VirtualFile file);
+
+  //
+  // Merge
+  //
+
+  @NotNull
+  public abstract MergeRequest createMergeRequest(@Nullable Project project,
+                                                  @Nullable FileType fileType,
+                                                  @NotNull Document output,
+                                                  @NotNull List<String> textContents,
+                                                  @Nullable String title,
+                                                  @NotNull List<String> titles,
+                                                  @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
+
+  @NotNull
+  public abstract MergeRequest createMergeRequest(@Nullable Project project,
+                                                  @NotNull VirtualFile output,
+                                                  @NotNull List<byte[]> byteContents,
+                                                  @Nullable String title,
+                                                  @NotNull List<String> contentTitles,
+                                                  @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
+
+  @NotNull
+  public abstract TextMergeRequest createTextMergeRequest(@Nullable Project project,
+                                                          @NotNull VirtualFile output,
+                                                          @NotNull List<byte[]> byteContents,
+                                                          @Nullable String title,
+                                                          @NotNull List<String> contentTitles,
+                                                          @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
+
+  @NotNull
+  public abstract MergeRequest createBinaryMergeRequest(@Nullable Project project,
+                                                        @NotNull VirtualFile output,
+                                                        @NotNull List<byte[]> byteContents,
+                                                        @Nullable String title,
+                                                        @NotNull List<String> contentTitles,
+                                                        @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
+
+  @NotNull
+  public abstract MergeRequest createMergeRequestFromFiles(@Nullable Project project,
+                                                           @NotNull VirtualFile output,
+                                                           @NotNull List<VirtualFile> contents,
+                                                           @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
+
+  @NotNull
+  public abstract MergeRequest createMergeRequestFromFiles(@Nullable Project project,
+                                                           @NotNull VirtualFile output,
+                                                           @NotNull List<VirtualFile> contents,
+                                                           @Nullable String title,
+                                                           @NotNull List<String> contentTitles,
+                                                           @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
+
+  @NotNull
+  public abstract TextMergeRequest createTextMergeRequestFromFiles(@Nullable Project project,
+                                                                   @NotNull VirtualFile output,
+                                                                   @NotNull List<VirtualFile> contents,
+                                                                   @Nullable String title,
+                                                                   @NotNull List<String> contentTitles,
+                                                                   @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException;
 }

platform/diff-api/src/com/intellij/diff/InvalidDiffRequestException.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff;
+
+public class InvalidDiffRequestException extends Exception {
+  public InvalidDiffRequestException(String message) {
+    super(message);
+  }
+
+  public InvalidDiffRequestException(String message, Throwable cause) {
+    super(message, cause);
+  }
+
+  public InvalidDiffRequestException(Throwable cause) {
+    super(cause);
+  }
+}

platform/diff-api/src/com/intellij/diff/chains/DiffRequestProducer.java

@@ -26,6 +26,12 @@ public interface DiffRequestProducer {
   @NotNull
   String getName();
 
+  /*
+   * Should be called either in EDT or without ReadLock.
+   * Some implementors might need WriteLock, so usage of Application.invokeAndWait() is possible.
+   *
+   * Valid ModalityState should be passed with ProgressIndicator.getModalityState().
+   */
   @CalledInBackground
   @NotNull
   DiffRequest process(@NotNull UserDataHolder context, @NotNull ProgressIndicator indicator)

platform/diff-api/src/com/intellij/diff/merge/MergeContext.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.Key;
+import com.intellij.openapi.util.UserDataHolder;
+import com.intellij.openapi.util.UserDataHolderBase;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public abstract class MergeContext implements UserDataHolder {
+  protected final UserDataHolderBase myUserDataHolder = new UserDataHolderBase();
+
+  @Nullable
+  public abstract Project getProject();
+
+  public abstract boolean isFocused();
+
+  public abstract void requestFocus();
+
+  @CalledInAwt
+  public abstract void finishMerge(@NotNull MergeResult result);
+
+  @Nullable
+  @Override
+  public <T> T getUserData(@NotNull Key<T> key) {
+    return myUserDataHolder.getUserData(key);
+  }
+
+  @Override
+  public <T> void putUserData(@NotNull Key<T> key, @Nullable T value) {
+    myUserDataHolder.putUserData(key, value);
+  }
+}

platform/diff-api/src/com/intellij/diff/merge/MergeRequest.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.openapi.util.Key;
+import com.intellij.openapi.util.UserDataHolder;
+import com.intellij.openapi.util.UserDataHolderBase;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public abstract class MergeRequest implements UserDataHolder {
+  protected final UserDataHolderBase myUserDataHolder = new UserDataHolderBase();
+
+  @Nullable
+  public abstract String getTitle();
+
+  /*
+   * Called on conflict resolve end.
+   */
+  @CalledInAwt
+  public abstract void applyResult(@NotNull MergeResult result);
+
+  @Nullable
+  @Override
+  public <T> T getUserData(@NotNull Key<T> key) {
+    return myUserDataHolder.getUserData(key);
+  }
+
+  @Override
+  public <T> void putUserData(@NotNull Key<T> key, @Nullable T value) {
+    myUserDataHolder.putUserData(key, value);
+  }
+}

platform/diff-api/src/com/intellij/diff/merge/MergeResult.java

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+public enum MergeResult {CANCEL, LEFT, RIGHT, RESOLVED}

platform/diff-api/src/com/intellij/diff/merge/MergeTool.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.openapi.Disposable;
+import com.intellij.openapi.actionSystem.AnAction;
+import com.intellij.openapi.extensions.ExtensionPointName;
+import com.intellij.openapi.util.BooleanGetter;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.util.List;
+
+public interface MergeTool {
+  ExtensionPointName<MergeTool> EP_NAME = ExtensionPointName.create("com.intellij.diff.merge.MergeTool");
+
+  @CalledInAwt
+  @NotNull
+  MergeViewer createComponent(@NotNull MergeContext context, @NotNull MergeRequest request);
+
+  boolean canShow(@NotNull MergeContext context, @NotNull MergeRequest request);
+
+  /*
+   * Merge viewer should call MergeContext.finishMerge(MergeResult) when processing is over.
+   *
+   * MergeRequest.applyResult() will be performed by the caller, so it shouldn't be called by MergeViewer directly.
+   */
+  interface MergeViewer extends Disposable {
+    @NotNull
+    JComponent getComponent();
+
+    @Nullable
+    JComponent getPreferredFocusedComponent();
+
+    @Nullable
+    Action getResolveAction(@NotNull MergeResult result);
+
+    @CalledInAwt
+    ToolbarComponents init();
+
+    @Override
+    @CalledInAwt
+    void dispose();
+  }
+
+  class ToolbarComponents {
+    @Nullable public List<AnAction> toolbarActions;
+    @Nullable public JComponent statusPanel;
+    @Nullable public BooleanGetter closeHandler; // return false if merge window should be prevented from closing and canceling resolve.
+  }
+}

platform/diff-api/src/com/intellij/diff/merge/TextMergeRequest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.contents.DocumentContent;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+public abstract class TextMergeRequest extends ThreesideMergeRequest {
+  @Override
+  @NotNull
+  public abstract List<DocumentContent> getContents();
+
+  @Override
+  @NotNull
+  public abstract DocumentContent getOutputContent();
+}

platform/diff-api/src/com/intellij/diff/merge/ThreesideMergeRequest.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.contents.DiffContent;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+public abstract class ThreesideMergeRequest extends MergeRequest {
+  /*
+   * 3 contents: left - middle - right (local - base - server)
+   */
+  @NotNull
+  public abstract List<? extends DiffContent> getContents();
+
+  @NotNull
+  public abstract DiffContent getOutputContent();
+
+  /**
+   * @return contents names. Should have same length as {@link #getContents()}
+   * Titles could be null.
+   */
+  @NotNull
+  public abstract List<String> getContentTitles();
+}

platform/diff-api/src/com/intellij/diff/requests/ComponentDiffRequest.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.requests;
+
+import com.intellij.diff.DiffContext;
+import org.jetbrains.annotations.NotNull;
+
+import javax.swing.*;
+
+public abstract class ComponentDiffRequest extends DiffRequest {
+  @NotNull
+  public abstract JComponent getComponent(@NotNull DiffContext context);
+}

platform/diff-api/src/com/intellij/diff/util/DiffUserDataKeys.java

@@ -20,6 +20,7 @@ import com.intellij.openapi.actionSystem.DataProvider;
 import com.intellij.openapi.util.Key;
 import com.intellij.openapi.util.Pair;
 
+import javax.swing.*;
 import java.util.List;
 
 public interface DiffUserDataKeys {
@@ -52,6 +53,7 @@ public interface DiffUserDataKeys {
   // Both data from DiffContext / DiffRequest will be used. Data from DiffRequest will be used first.
   //
 
+  Key<List<JComponent>> NOTIFICATIONS = Key.create("Diff.Notifications");
   Key<List<AnAction>> CONTEXT_ACTIONS = Key.create("Diff.ContextActions");
   Key<DataProvider> DATA_PROVIDER = Key.create("Diff.DataProvider");
   Key<Boolean> GO_TO_SOURCE_DISABLE = Key.create("Diff.GoToSourceDisable");

platform/diff-api/src/com/intellij/diff/util/Side.java

@@ -34,6 +34,13 @@ public enum Side {
     myIndex = index;
   }
 
+  @NotNull
+  public static Side fromIndex(int index) {
+    if (index == 0) return LEFT;
+    if (index == 1) return RIGHT;
+    throw new IndexOutOfBoundsException("index: " + index);
+  }
+
   @NotNull
   public static Side fromLeft(boolean isLeft) {
     return isLeft ? LEFT : RIGHT;

platform/diff-api/src/com/intellij/diff/util/ThreeSide.java

@@ -32,6 +32,14 @@ public enum ThreeSide {
     myIndex = index;
   }
 
+  @NotNull
+  public static ThreeSide fromIndex(int index) {
+    if (index == 0) return LEFT;
+    if (index == 1) return BASE;
+    if (index == 2) return RIGHT;
+    throw new IndexOutOfBoundsException("index: " + index);
+  }
+
   public int getIndex() {
     return myIndex;
   }

platform/diff-impl/diff-impl.iml

@@ -2,15 +2,13 @@
 <module type="JAVA_MODULE" version="4">
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
-    <content url="file://$MODULE_DIR$">
+    <content url="file://$MODULE_DIR$/src">
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/tests" isTestSource="true" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="module" module-name="core-api" />
     <orderEntry type="module" module-name="diff-api" exported="" />
-    <orderEntry type="module" module-name="testFramework" scope="TEST" />
     <orderEntry type="module" module-name="platform-api" />
     <orderEntry type="module" module-name="platform-impl" />
     <orderEntry type="module" module-name="vcs-api-core" />

platform/diff-impl/diff-tests.iml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$/tests">
+      <sourceFolder url="file://$MODULE_DIR$/tests" isTestSource="true" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="module" module-name="core-api" />
+    <orderEntry type="module" module-name="diff-api" exported="" />
+    <orderEntry type="module" module-name="testFramework" scope="TEST" />
+    <orderEntry type="module" module-name="platform-api" />
+    <orderEntry type="module" module-name="platform-impl" />
+    <orderEntry type="module" module-name="vcs-api-core" />
+    <orderEntry type="module" module-name="diff-impl" scope="TEST" />
+  </component>
+</module>

platform/diff-impl/src/com/intellij/diff/DiffContentFactoryImpl.java

@@ -17,7 +17,6 @@ package com.intellij.diff;
 
 import com.intellij.diff.contents.*;
 import com.intellij.openapi.application.ApplicationManager;
-import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.editor.EditorFactory;
@@ -119,6 +118,13 @@ public class DiffContentFactoryImpl extends DiffContentFactory {
     return new FileDocumentContentImpl(project, document, file);
   }
 
+  @Override
+  @Nullable
+  public FileContent createFile(@Nullable Project project, @NotNull VirtualFile file) {
+    if (file.isDirectory()) return null;
+    return (FileContent)create(project, file);
+  }
+
   @Override
   @NotNull
   public DiffContent createClipboardContent() {

platform/diff-impl/src/com/intellij/diff/DiffContextEx.java

@@ -18,8 +18,17 @@ package com.intellij.diff;
 public abstract class DiffContextEx extends DiffContext {
   /*
    * Reopen current DiffRequest.
+   *
    * perform the same procedure as on switching between DiffRequests or between DiffViewers.
    * this can be used, if some change in request or settings was made, and we need to reopen DiffViewer to apply them.
    */
+  public abstract void reopenDiffRequest();
+
+  /*
+   * Drop cached DiffRequest version (if any) and reopen current DiffRequest.
+   *
+   * perform the same procedure as on opening DiffRequests for the first time.
+   * this can be used, if some change in request or settings was made, and we need to reload DiffRequest to apply them.
+   */
   public abstract void reloadDiffRequest();
 }

platform/diff-impl/src/com/intellij/diff/DiffManagerImpl.java

@@ -19,15 +19,18 @@ import com.intellij.diff.chains.DiffRequestChain;
 import com.intellij.diff.chains.SimpleDiffRequestChain;
 import com.intellij.diff.impl.DiffRequestPanelImpl;
 import com.intellij.diff.impl.DiffWindow;
+import com.intellij.diff.merge.*;
 import com.intellij.diff.requests.DiffRequest;
 import com.intellij.diff.tools.binary.BinaryDiffTool;
 import com.intellij.diff.tools.dir.DirDiffTool;
 import com.intellij.diff.tools.external.ExternalDiffTool;
+import com.intellij.diff.tools.external.ExternalMergeTool;
 import com.intellij.diff.tools.fragmented.UnifiedDiffTool;
 import com.intellij.diff.tools.simple.SimpleDiffTool;
 import com.intellij.openapi.Disposable;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Disposer;
+import org.jetbrains.annotations.CalledInAwt;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -93,4 +96,29 @@ public class DiffManagerImpl extends DiffManagerEx {
     Collections.addAll(result, DiffTool.EP_NAME.getExtensions());
     return result;
   }
+
+  @NotNull
+  @Override
+  public List<MergeTool> getMergeTools() {
+    List<MergeTool> result = new ArrayList<MergeTool>();
+    Collections.addAll(result, MergeTool.EP_NAME.getExtensions());
+    result.add(TextMergeTool.INSTANCE);
+    result.add(BinaryMergeTool.INSTANCE);
+    return result;
+  }
+
+  @CalledInAwt
+  public void showMerge(@Nullable Project project, @NotNull MergeRequest request) {
+    if (ExternalMergeTool.isDefault()) {
+      ExternalMergeTool.show(project, request);
+      return;
+    }
+
+    showMergeBuiltin(project, request);
+  }
+
+  @CalledInAwt
+  public void showMergeBuiltin(@Nullable Project project, @NotNull MergeRequest request) {
+    new MergeWindow(project, request).show();
+  }
 }

platform/diff-impl/src/com/intellij/diff/DiffRequestFactoryImpl.java

@@ -16,18 +16,40 @@
 package com.intellij.diff;
 
 import com.intellij.diff.contents.DiffContent;
+import com.intellij.diff.contents.DocumentContent;
+import com.intellij.diff.contents.FileAwareDocumentContent;
+import com.intellij.diff.contents.FileContent;
+import com.intellij.diff.merge.MergeRequest;
+import com.intellij.diff.merge.MergeResult;
+import com.intellij.diff.merge.TextMergeRequest;
+import com.intellij.diff.requests.BinaryMergeRequestImpl;
 import com.intellij.diff.requests.ContentDiffRequest;
 import com.intellij.diff.requests.SimpleDiffRequest;
+import com.intellij.diff.requests.TextMergeRequestImpl;
+import com.intellij.diff.util.DiffUtil;
 import com.intellij.openapi.diff.DiffBundle;
+import com.intellij.openapi.editor.Document;
+import com.intellij.openapi.fileEditor.FileDocumentManager;
+import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Comparing;
 import com.intellij.openapi.vcs.FilePath;
 import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.util.Consumer;
+import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
 public class DiffRequestFactoryImpl extends DiffRequestFactory {
-  private DiffContentFactory myContentFactory = DiffContentFactory.getInstance();
+  private final DiffContentFactory myContentFactory = DiffContentFactory.getInstance();
+
+  //
+  // Diff
+  //
 
   @Override
   @NotNull
@@ -57,6 +79,10 @@ public class DiffRequestFactoryImpl extends DiffRequestFactory {
     return new SimpleDiffRequest(title, content1, content2, title1, title2);
   }
 
+  //
+  // Titles
+  //
+
   @Override
   @NotNull
   public String getContentTitle(@NotNull VirtualFile file) {
@@ -147,4 +173,195 @@ public class DiffRequestFactoryImpl extends DiffRequestFactory {
       }
     }
   }
+
+  //
+  // Merge
+  //
+
+  @NotNull
+  public MergeRequest createMergeRequest(@Nullable Project project,
+                                         @Nullable FileType fileType,
+                                         @NotNull Document outputDocument,
+                                         @NotNull List<String> textContents,
+                                         @Nullable String title,
+                                         @NotNull List<String> titles,
+                                         @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (textContents.size() != 3) throw new IllegalArgumentException();
+    if (titles.size() != 3) throw new IllegalArgumentException();
+
+    if (!DiffUtil.canMakeWritable(outputDocument)) throw new InvalidDiffRequestException("Output is read only");
+
+    DocumentContent outputContent = myContentFactory.create(project, outputDocument, fileType);
+    CharSequence originalContent = outputDocument.getImmutableCharSequence();
+
+    List<DocumentContent> contents = new ArrayList<DocumentContent>(3);
+    for (String text : textContents) {
+      contents.add(myContentFactory.create(text, fileType));
+    }
+
+    return new TextMergeRequestImpl(project, outputContent, originalContent, contents, title, titles, applyCallback);
+  }
+
+  @NotNull
+  @Override
+  public MergeRequest createMergeRequest(@Nullable Project project,
+                                         @NotNull VirtualFile output,
+                                         @NotNull List<byte[]> byteContents,
+                                         @Nullable String title,
+                                         @NotNull List<String> contentTitles,
+                                         @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (byteContents.size() != 3) throw new IllegalArgumentException();
+    if (contentTitles.size() != 3) throw new IllegalArgumentException();
+
+    try {
+      return createTextMergeRequest(project, output, byteContents, title, contentTitles, applyCallback);
+    }
+    catch (InvalidDiffRequestException e) {
+      return createBinaryMergeRequest(project, output, byteContents, title, contentTitles, applyCallback);
+    }
+  }
+
+  @NotNull
+  @Override
+  public TextMergeRequest createTextMergeRequest(@Nullable Project project,
+                                                 @NotNull VirtualFile output,
+                                                 @NotNull List<byte[]> byteContents,
+                                                 @Nullable String title,
+                                                 @NotNull List<String> contentTitles,
+                                                 @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (byteContents.size() != 3) throw new IllegalArgumentException();
+    if (contentTitles.size() != 3) throw new IllegalArgumentException();
+
+    final Document outputDocument = FileDocumentManager.getInstance().getDocument(output);
+    if (outputDocument == null) throw new InvalidDiffRequestException("Can't get output document: " + output.getPresentableUrl());
+    if (!DiffUtil.canMakeWritable(outputDocument)) throw new InvalidDiffRequestException("Output is read only: " + output.getPresentableUrl());
+
+    DocumentContent outputContent = myContentFactory.create(project, outputDocument);
+    CharSequence originalContent = outputDocument.getImmutableCharSequence();
+
+    List<DocumentContent> contents = new ArrayList<DocumentContent>(3);
+    for (byte[] bytes : byteContents) {
+      contents.add(FileAwareDocumentContent.create(project, bytes, output));
+    }
+
+    return new TextMergeRequestImpl(project, outputContent, originalContent, contents, title, contentTitles, applyCallback);
+  }
+
+  @NotNull
+  @Override
+  public MergeRequest createBinaryMergeRequest(@Nullable Project project,
+                                               @NotNull VirtualFile output,
+                                               @NotNull List<byte[]> byteContents,
+                                               @Nullable String title,
+                                               @NotNull List<String> contentTitles,
+                                               @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (byteContents.size() != 3) throw new IllegalArgumentException();
+    if (contentTitles.size() != 3) throw new IllegalArgumentException();
+
+    try {
+      FileContent outputContent = myContentFactory.createFile(project, output);
+      if (outputContent == null) throw new InvalidDiffRequestException("Can't create output content: " + output);
+      byte[] originalContent = output.contentsToByteArray();
+
+      List<DiffContent> contents = new ArrayList<DiffContent>(3);
+      for (byte[] bytes : byteContents) {
+        contents.add(myContentFactory.createFromBytes(project, output, bytes));
+      }
+
+      return new BinaryMergeRequestImpl(outputContent, originalContent, contents, byteContents, title, contentTitles, applyCallback);
+    }
+    catch (IOException e) {
+      throw new InvalidDiffRequestException("Can't read from file", e);
+    }
+  }
+
+  @NotNull
+  @Override
+  public MergeRequest createMergeRequestFromFiles(@Nullable Project project,
+                                                  @NotNull VirtualFile output,
+                                                  @NotNull List<VirtualFile> fileContents,
+                                                  @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    String title = "Merge " + output.getPresentableUrl();
+    List<String> titles = ContainerUtil.list("Your Version", "Base Version", "Their Version");
+    return createMergeRequestFromFiles(project, output, fileContents, title, titles, applyCallback);
+  }
+
+  @NotNull
+  @Override
+  public MergeRequest createMergeRequestFromFiles(@Nullable Project project,
+                                                  @NotNull VirtualFile output,
+                                                  @NotNull List<VirtualFile> fileContents,
+                                                  @Nullable String title,
+                                                  @NotNull List<String> contentTitles,
+                                                  @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (fileContents.size() != 3) throw new IllegalArgumentException();
+    if (contentTitles.size() != 3) throw new IllegalArgumentException();
+
+    try {
+      return createTextMergeRequestFromFiles(project, output, fileContents, title, contentTitles, applyCallback);
+    }
+    catch (InvalidDiffRequestException e) {
+      return createBinaryMergeRequestFromFiles(project, output, fileContents, title, contentTitles, applyCallback);
+    }
+  }
+
+  @NotNull
+  @Override
+  public TextMergeRequest createTextMergeRequestFromFiles(@Nullable Project project,
+                                                          @NotNull VirtualFile output,
+                                                          @NotNull List<VirtualFile> fileContents,
+                                                          @Nullable String title,
+                                                          @NotNull List<String> contentTitles,
+                                                          @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (fileContents.size() != 3) throw new IllegalArgumentException();
+    if (contentTitles.size() != 3) throw new IllegalArgumentException();
+
+    final Document outputDocument = FileDocumentManager.getInstance().getDocument(output);
+    if (outputDocument == null) throw new InvalidDiffRequestException("Can't get output document: " + output.getPresentableUrl());
+    if (!DiffUtil.canMakeWritable(outputDocument)) throw new InvalidDiffRequestException("Output is read only: " + output.getPresentableUrl());
+
+    DocumentContent outputContent = myContentFactory.create(project, outputDocument);
+    CharSequence originalContent = outputDocument.getImmutableCharSequence();
+
+    List<DocumentContent> contents = new ArrayList<DocumentContent>(3);
+    for (VirtualFile file : fileContents) {
+      DocumentContent document = myContentFactory.createDocument(project, file);
+      if (document == null) throw new InvalidDiffRequestException("Can't get text content: " + file.getPresentableUrl());
+      contents.add(document);
+    }
+
+    return new TextMergeRequestImpl(project, outputContent, originalContent, contents, title, contentTitles, applyCallback);
+  }
+
+  @NotNull
+  public MergeRequest createBinaryMergeRequestFromFiles(@Nullable Project project,
+                                                        @NotNull VirtualFile output,
+                                                        @NotNull List<VirtualFile> fileContents,
+                                                        @Nullable String title,
+                                                        @NotNull List<String> contentTitles,
+                                                        @Nullable Consumer<MergeResult> applyCallback) throws InvalidDiffRequestException {
+    if (fileContents.size() != 3) throw new IllegalArgumentException();
+    if (contentTitles.size() != 3) throw new IllegalArgumentException();
+
+
+    try {
+      FileContent outputContent = myContentFactory.createFile(project, output);
+      if (outputContent == null) throw new InvalidDiffRequestException("Can't create output content: " + output.getPresentableUrl());
+      byte[] originalContent = output.contentsToByteArray();
+
+      List<DiffContent> contents = new ArrayList<DiffContent>(3);
+      List<byte[]> byteContents = new ArrayList<byte[]>(3);
+      for (VirtualFile file : fileContents) {
+        FileContent content = myContentFactory.createFile(project, file);
+        if (content == null) throw new InvalidDiffRequestException("Can't create content: " + file.getPresentableUrl());
+        contents.add(content);
+        byteContents.add(file.contentsToByteArray()); // TODO: we can read contents from file when needed
+      }
+
+      return new BinaryMergeRequestImpl(outputContent, originalContent, contents, byteContents, title, contentTitles, applyCallback);
+    }
+    catch (IOException e) {
+      throw new InvalidDiffRequestException("Can't read from file", e);
+    }
+  }
 }

platform/diff-impl/src/com/intellij/diff/actions/impl/SetEditorSettingsAction.java

@@ -19,6 +19,7 @@ import com.intellij.diff.tools.util.base.TextDiffSettingsHolder;
 import com.intellij.icons.AllIcons;
 import com.intellij.openapi.actionSystem.*;
 import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.editor.ex.EditorGutterComponentEx;
 import com.intellij.openapi.editor.impl.EditorImpl;
 import com.intellij.openapi.project.DumbAware;
 import org.jetbrains.annotations.NotNull;
@@ -39,6 +40,10 @@ public class SetEditorSettingsAction extends ActionGroup implements DumbAware {
     myTextSettings = settings;
     myEditors = editors;
 
+    for (Editor editor : myEditors) {
+      ((EditorGutterComponentEx)editor.getGutter()).setGutterPopupGroup(this);
+    }
+
     myActions = new EditorSettingToggleAction[]{
       new EditorSettingToggleAction("EditorToggleShowWhitespaces") {
         @Override

platform/diff-impl/src/com/intellij/diff/applications/ApplicationStarterBase.java

@@ -19,6 +19,7 @@ import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.application.ApplicationStarterEx;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
+import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.Messages;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.LocalFileSystem;
@@ -125,4 +126,9 @@ public abstract class ApplicationStarterBase extends ApplicationStarterEx {
   public boolean canProcessExternalCommandLine() {
     return true;
   }
+
+  @Nullable
+  protected Project getProject() {
+    return null; // TODO: try to guess project
+  }
 }

platform/diff-impl/src/com/intellij/diff/applications/DiffApplication.java

@@ -21,7 +21,6 @@ import com.intellij.diff.DiffRequestFactory;
 import com.intellij.diff.requests.DiffRequest;
 import com.intellij.openapi.application.ApplicationNamesInfo;
 import com.intellij.openapi.diff.DiffBundle;
-import com.intellij.openapi.project.DefaultProjectFactory;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.VfsUtil;
 import com.intellij.openapi.vfs.VirtualFile;
@@ -47,8 +46,6 @@ public class DiffApplication extends ApplicationStarterBase {
   }
 
   public void processCommand(@NotNull String[] args, @Nullable String currentDirectory) throws Exception {
-    // TODO: try to guess 'right' project ?
-
     final String path1 = args[1];
     final String path2 = args[2];
 
@@ -59,9 +56,10 @@ public class DiffApplication extends ApplicationStarterBase {
     if (file2 == null) throw new Exception("Can't find file " + path2);
 
     VfsUtil.markDirtyAndRefresh(false, false, false, file1, file2);
-    DiffRequest request = DiffRequestFactory.getInstance().createFromFiles(null, file1, file2);
 
-    Project project = DefaultProjectFactory.getInstance().getDefaultProject();
+    Project project = getProject();
+
+    DiffRequest request = DiffRequestFactory.getInstance().createFromFiles(project, file1, file2);
     DiffManagerEx.getInstance().showDiffBuiltin(project, request, DiffDialogHints.MODAL);
   }
 }

platform/diff-impl/src/com/intellij/diff/applications/MergeApplication.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.applications;
+
+import com.intellij.diff.DiffManagerEx;
+import com.intellij.diff.DiffRequestFactory;
+import com.intellij.diff.merge.MergeRequest;
+import com.intellij.openapi.application.ApplicationNamesInfo;
+import com.intellij.openapi.diff.DiffBundle;
+import com.intellij.openapi.editor.Document;
+import com.intellij.openapi.fileEditor.FileDocumentManager;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.util.containers.ContainerUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+
+@SuppressWarnings({"UseOfSystemOutOrSystemErr", "CallToPrintStackTrace"})
+public class MergeApplication extends ApplicationStarterBase {
+  @Override
+  protected boolean checkArguments(@NotNull String[] args) {
+    return (args.length == 4 || args.length == 5) && "merge".equals(args[0]);
+  }
+
+  @Override
+  public String getCommandName() {
+    return "merge";
+  }
+
+  @NotNull
+  public String getUsageMessage() {
+    final String scriptName = ApplicationNamesInfo.getInstance().getScriptName();
+    return DiffBundle.message("merge.application.usage.parameters.and.description", scriptName);
+  }
+
+  public void processCommand(@NotNull String[] args, @Nullable String currentDirectory) throws Exception {
+    // TODO: try to guess 'right' project ?
+
+    final String path1 = args[1];
+    final String path2 = args[2];
+    final String path3 = args[3];
+    final String path4 = args.length == 5 ? args[4] : args[3];
+
+    final VirtualFile file1 = findFile(path1, currentDirectory);
+    final VirtualFile file2 = findFile(path2, currentDirectory);
+    final VirtualFile file3 = findFile(path3, currentDirectory);
+    final VirtualFile file4 = findFile(path4, currentDirectory);
+
+    if (file1 == null) throw new Exception("Can't find file " + path1);
+    if (file2 == null) throw new Exception("Can't find file " + path2);
+    if (file3 == null) throw new Exception("Can't find file " + path3);
+    if (file4 == null) throw new Exception("Can't find file " + path4);
+
+    file1.refresh(false, true);
+    file2.refresh(false, true);
+    file3.refresh(false, true);
+    file4.refresh(false, true);
+
+    Project project = getProject();
+
+    List<VirtualFile> contents = ContainerUtil.list(file1, file3, file2); // left, base, right
+    MergeRequest request = DiffRequestFactory.getInstance().createMergeRequestFromFiles(project, file4, contents, null);
+
+    DiffManagerEx.getInstance().showMergeBuiltin(project, request);
+
+    Document document = FileDocumentManager.getInstance().getCachedDocument(file4);
+    if (document != null) FileDocumentManager.getInstance().saveDocument(document);
+  }
+}

platform/diff-impl/src/com/intellij/diff/impl/CacheDiffRequestChainProcessor.java

@@ -33,7 +33,6 @@ import com.intellij.openapi.progress.ProgressIndicator;
 import com.intellij.openapi.progress.util.ProgressWindow;
 import com.intellij.openapi.project.DumbAwareAction;
 import com.intellij.openapi.project.Project;
-import com.intellij.openapi.util.Disposer;
 import com.intellij.util.Consumer;
 import com.intellij.util.Function;
 import com.intellij.util.containers.ContainerUtil;
@@ -64,8 +63,18 @@ public abstract class CacheDiffRequestChainProcessor extends DiffRequestProcesso
   // Update
   //
 
+  @Override
+  protected void reloadRequest() {
+    updateRequest(true, false, null);
+  }
+
   @CalledInAwt
   public void updateRequest(final boolean force, @Nullable final ScrollToPolicy scrollToChangePolicy) {
+    updateRequest(force, true, scrollToChangePolicy);
+  }
+
+  @CalledInAwt
+  public void updateRequest(final boolean force, boolean useCache, @Nullable final ScrollToPolicy scrollToChangePolicy) {
     List<? extends DiffRequestProducer> requests = myRequestChain.getRequests();
     int index = myRequestChain.getIndex();
     if (index < 0 || index >= requests.size()) {
@@ -75,7 +84,7 @@ public abstract class CacheDiffRequestChainProcessor extends DiffRequestProcesso
 
     final DiffRequestProducer producer = requests.get(index);
 
-    DiffRequest request = loadRequestFast(producer);
+    DiffRequest request = loadRequestFast(producer, useCache);
     if (request != null) {
       applyRequest(request, force, scrollToChangePolicy);
       return;
@@ -107,7 +116,8 @@ public abstract class CacheDiffRequestChainProcessor extends DiffRequestProcesso
   }
 
   @Nullable
-  protected DiffRequest loadRequestFast(@NotNull DiffRequestProducer producer) {
+  protected DiffRequest loadRequestFast(@NotNull DiffRequestProducer producer, boolean useCache) {
+    if (!useCache) return null;
     return myRequestCache.get(producer);
   }
 
@@ -126,6 +136,7 @@ public abstract class CacheDiffRequestChainProcessor extends DiffRequestProcesso
       return new ErrorDiffRequest(producer, e);
     }
     catch (Exception e) {
+      LOG.warn(e);
       return new ErrorDiffRequest(producer, e);
     }
   }

platform/diff-impl/src/com/intellij/diff/impl/DiffRequestPanelImpl.java

@@ -32,10 +32,10 @@ import java.awt.*;
 
 public class DiffRequestPanelImpl implements DiffRequestPanel {
   @NotNull private final JPanel myPanel;
-  @NotNull private final MyCacheDiffRequestChainProcessor myProcessor;
+  @NotNull private final MyDiffRequestProcessor myProcessor;
 
   public DiffRequestPanelImpl(@Nullable Project project, @Nullable Window window) {
-    myProcessor = new MyCacheDiffRequestChainProcessor(project, window);
+    myProcessor = new MyDiffRequestProcessor(project, window);
     myProcessor.putContextUserData(DiffUserDataKeys.DO_NOT_CHANGE_WINDOW_TITLE, true);
 
     myPanel = new JPanel(new BorderLayout()) {
@@ -81,12 +81,12 @@ public class DiffRequestPanelImpl implements DiffRequestPanel {
     Disposer.dispose(myProcessor);
   }
 
-  private static class MyCacheDiffRequestChainProcessor extends DiffRequestProcessor {
+  private static class MyDiffRequestProcessor extends DiffRequestProcessor {
     @Nullable private final Window myWindow;
 
     @NotNull private DiffRequest myRequest = NoDiffRequest.INSTANCE;
 
-    public MyCacheDiffRequestChainProcessor(@Nullable Project project, @Nullable Window window) {
+    public MyDiffRequestProcessor(@Nullable Project project, @Nullable Window window) {
       super(project);
       myWindow = window;
     }

platform/diff-impl/src/com/intellij/diff/impl/DiffRequestProcessor.java

@@ -158,6 +158,11 @@ public abstract class DiffRequestProcessor implements Disposable {
   // Update
   //
 
+  @CalledInAwt
+  protected void reloadRequest() {
+    updateRequest(true);
+  }
+
   @CalledInAwt
   public void updateRequest() {
     updateRequest(false);
@@ -445,13 +450,13 @@ public abstract class DiffRequestProcessor implements Disposable {
 
     myToolbarPanel.setContent(toolbar.getComponent());
     for (AnAction action : group.getChildren(null)) {
-      action.registerCustomShortcutSet(action.getShortcutSet(), myMainPanel);
+      DiffUtil.registerAction(action, myMainPanel);
     }
   }
 
   protected void buildActionPopup(@Nullable List<AnAction> viewerActions) {
     ShowActionGroupPopupAction action = new ShowActionGroupPopupAction();
-    action.registerCustomShortcutSet(action.getShortcutSet(), myMainPanel);
+    DiffUtil.registerAction(action, myMainPanel);
 
     myPopupActionGroup = collectPopupActions(viewerActions);
   }
@@ -902,10 +907,15 @@ public abstract class DiffRequestProcessor implements Disposable {
     }
 
     @Override
-    public void reloadDiffRequest() {
+    public void reopenDiffRequest() {
       updateRequest(true);
     }
 
+    @Override
+    public void reloadDiffRequest() {
+      reloadRequest();
+    }
+
     @Nullable
     @Override
     public Project getProject() {

platform/diff-impl/src/com/intellij/diff/impl/DiffWindowBase.java

@@ -63,6 +63,8 @@ public abstract class DiffWindowBase {
           myProcessor.requestFocus(); // TODO: not needed for modal dialogs. Make a flag in WindowWrapperBuilder ?
         }
       })
+      .setOkAction(myHints.getOkAction())
+      .setCancelAction(myHints.getCancelAction())
       .build();
     myWrapper.setImage(ImageLoader.loadFromResource("/diff/Diff.png"));
     Disposer.register(myWrapper, myProcessor);

platform/diff-impl/src/com/intellij/diff/merge/BinaryMergeTool.java

@@ -0,0 +1,179 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.DiffContext;
+import com.intellij.diff.FrameDiffTool;
+import com.intellij.diff.contents.DiffContent;
+import com.intellij.diff.requests.ContentDiffRequest;
+import com.intellij.diff.requests.DiffRequest;
+import com.intellij.diff.requests.SimpleDiffRequest;
+import com.intellij.diff.tools.binary.ThreesideBinaryDiffViewer;
+import com.intellij.diff.tools.holders.BinaryEditorHolder;
+import com.intellij.openapi.diff.DiffBundle;
+import com.intellij.openapi.ui.Messages;
+import com.intellij.openapi.util.BooleanGetter;
+import com.intellij.openapi.util.Disposer;
+import com.intellij.util.containers.ContainerUtil;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.awt.event.ActionEvent;
+import java.util.List;
+
+public class BinaryMergeTool implements MergeTool {
+  public static final BinaryMergeTool INSTANCE = new BinaryMergeTool();
+
+  @NotNull
+  @Override
+  public MergeViewer createComponent(@NotNull MergeContext context, @NotNull MergeRequest request) {
+    return new BinaryMergeViewer(context, (ThreesideMergeRequest)request);
+  }
+
+  @Override
+  public boolean canShow(@NotNull MergeContext context, @NotNull MergeRequest request) {
+    if (!(request instanceof ThreesideMergeRequest)) return false;
+
+    MergeUtil.ProxyDiffContext diffContext = new MergeUtil.ProxyDiffContext(context);
+    for (DiffContent diffContent : ((ThreesideMergeRequest)request).getContents()) {
+      if (!BinaryEditorHolder.BinaryEditorHolderFactory.INSTANCE.canShowContent(diffContent, diffContext)) return false;
+    }
+
+    return true;
+  }
+
+  public static class BinaryMergeViewer implements MergeViewer {
+    @NotNull private final MergeContext myMergeContext;
+    @NotNull private final ThreesideMergeRequest myMergeRequest;
+
+    @NotNull private final DiffContext myDiffContext;
+    @NotNull private final ContentDiffRequest myDiffRequest;
+
+    @NotNull private final MyThreesideViewer myViewer;
+
+    public BinaryMergeViewer(@NotNull MergeContext context, @NotNull ThreesideMergeRequest request) {
+      myMergeContext = context;
+      myMergeRequest = request;
+
+      myDiffContext = new MergeUtil.ProxyDiffContext(myMergeContext);
+      myDiffRequest = new SimpleDiffRequest(myMergeRequest.getTitle(),
+                                            getDiffContents(myMergeRequest),
+                                            getDiffContentTitles(myMergeRequest));
+
+      myViewer = new MyThreesideViewer(myDiffContext, myDiffRequest);
+    }
+
+    @NotNull
+    private static List<DiffContent> getDiffContents(@NotNull ThreesideMergeRequest mergeRequest) {
+      return ContainerUtil.newArrayList(mergeRequest.getContents());
+    }
+
+    @NotNull
+    private static List<String> getDiffContentTitles(@NotNull ThreesideMergeRequest mergeRequest) {
+      return MergeUtil.notNullizeContentTitles(mergeRequest.getContentTitles());
+    }
+
+    //
+    // Impl
+    //
+
+    @NotNull
+    @Override
+    public JComponent getComponent() {
+      return myViewer.getComponent();
+    }
+
+    @Nullable
+    @Override
+    public JComponent getPreferredFocusedComponent() {
+      return myViewer.getPreferredFocusedComponent();
+    }
+
+    @NotNull
+    @Override
+    public ToolbarComponents init() {
+      ToolbarComponents components = new ToolbarComponents();
+
+      FrameDiffTool.ToolbarComponents init = myViewer.init();
+      components.statusPanel = init.statusPanel;
+      components.toolbarActions = init.toolbarActions;
+
+      components.closeHandler = new BooleanGetter() {
+        @Override
+        public boolean get() {
+          return Messages.showYesNoDialog(getComponent().getRootPane(),
+                                          DiffBundle.message("merge.dialog.exit.without.applying.changes.confirmation.message"),
+                                          DiffBundle.message("cancel.visual.merge.dialog.title"), Messages.getQuestionIcon()) == Messages.YES;
+        }
+      };
+
+      return components;
+    }
+
+    @Nullable
+    @Override
+    public Action getResolveAction(@NotNull final MergeResult result) {
+      if (result == MergeResult.RESOLVED) return null;
+
+      String caption = MergeUtil.getResolveActionTitle(result, myMergeRequest, myMergeContext);
+      return new AbstractAction(caption) {
+        @Override
+        public void actionPerformed(ActionEvent e) {
+          if (result == MergeResult.CANCEL) {
+            if (Messages.showYesNoDialog(getComponent().getRootPane(),
+                                         DiffBundle.message("merge.dialog.exit.without.applying.changes.confirmation.message"),
+                                         DiffBundle.message("cancel.visual.merge.dialog.title"), Messages.getQuestionIcon()) != Messages.YES) {
+              return;
+            }
+          }
+
+          myMergeContext.finishMerge(result);
+        }
+      };
+    }
+
+    @Override
+    public void dispose() {
+      Disposer.dispose(myViewer);
+    }
+
+    //
+    // Getters
+    //
+
+    @NotNull
+    public MyThreesideViewer getViewer() {
+      return myViewer;
+    }
+
+    //
+    // Viewer
+    //
+
+    private static class MyThreesideViewer extends ThreesideBinaryDiffViewer {
+      public MyThreesideViewer(@NotNull DiffContext context, @NotNull DiffRequest request) {
+        super(context, request);
+      }
+
+      @Override
+      @CalledInAwt
+      public void rediff(boolean trySync) {
+      }
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/merge/ErrorMergeTool.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.util.DiffUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+
+public class ErrorMergeTool implements MergeTool {
+  public static final ErrorMergeTool INSTANCE = new ErrorMergeTool();
+
+  @NotNull
+  @Override
+  public MergeViewer createComponent(@NotNull MergeContext context, @NotNull MergeRequest request) {
+    return new MyViewer(context, request);
+  }
+
+  @Override
+  public boolean canShow(@NotNull MergeContext context, @NotNull MergeRequest request) {
+    return true;
+  }
+
+  private static class MyViewer implements MergeViewer {
+    @NotNull private final MergeContext myMergeContext;
+    @NotNull private final MergeRequest myMergeRequest;
+
+    @NotNull private final JPanel myPanel;
+
+    public MyViewer(@NotNull MergeContext context, @NotNull MergeRequest request) {
+      myMergeContext = context;
+      myMergeRequest = request;
+
+      myPanel = new JPanel(new BorderLayout());
+      myPanel.add(createComponent(), BorderLayout.CENTER);
+    }
+
+    @NotNull
+    private JComponent createComponent() {
+      return DiffUtil.createMessagePanel("Can't show diff");
+    }
+
+    @NotNull
+    @Override
+    public JComponent getComponent() {
+      return myPanel;
+    }
+
+    @Nullable
+    @Override
+    public JComponent getPreferredFocusedComponent() {
+      return null;
+    }
+
+    @NotNull
+    @Override
+    public ToolbarComponents init() {
+      return new ToolbarComponents();
+    }
+
+    @Nullable
+    @Override
+    public Action getResolveAction(@NotNull final MergeResult result) {
+      if (result == MergeResult.RESOLVED) return null;
+
+      String caption = MergeUtil.getResolveActionTitle(result, myMergeRequest, myMergeContext);
+      return new AbstractAction(caption) {
+        @Override
+        public void actionPerformed(ActionEvent e) {
+          myMergeContext.finishMerge(result);
+        }
+      };
+    }
+
+    @Override
+    public void dispose() {
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/merge/MergeRequestProcessor.java

@@ -0,0 +1,440 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.DiffManagerEx;
+import com.intellij.diff.actions.impl.NextDifferenceAction;
+import com.intellij.diff.actions.impl.PrevDifferenceAction;
+import com.intellij.diff.tools.util.DiffDataKeys;
+import com.intellij.diff.tools.util.PrevNextDifferenceIterable;
+import com.intellij.diff.util.DiffPlaces;
+import com.intellij.diff.util.DiffUserDataKeys;
+import com.intellij.diff.util.DiffUserDataKeysEx;
+import com.intellij.diff.util.DiffUtil;
+import com.intellij.ide.DataManager;
+import com.intellij.ide.impl.DataManagerImpl;
+import com.intellij.openapi.Disposable;
+import com.intellij.openapi.actionSystem.*;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.BooleanGetter;
+import com.intellij.openapi.util.Disposer;
+import com.intellij.openapi.util.Key;
+import com.intellij.openapi.wm.ex.IdeFocusTraversalPolicy;
+import com.intellij.ui.components.panels.Wrapper;
+import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.ui.UIUtil;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.awt.*;
+import java.util.List;
+
+// TODO: support merge request chains
+// idea - to keep in memory all viewers that were modified (so binary conflict is not the case and OOM shouldn't be too often)
+// suspend() / resume() methods for viewers? To not interfere with MergeRequest lifecycle: single request -> single viewer -> single applyResult()
+public abstract class MergeRequestProcessor implements Disposable {
+  private static final Logger LOG = Logger.getInstance(MergeRequestProcessor.class);
+
+  private boolean myDisposed;
+
+  @Nullable private final Project myProject;
+  @NotNull private final MergeContext myContext;
+
+  @NotNull private final List<MergeTool> myAvailableTools;
+
+  @NotNull private final JPanel myPanel;
+  @NotNull private final MyPanel myMainPanel;
+  @NotNull private final Wrapper myContentPanel;
+  @NotNull private final Wrapper myToolbarPanel;
+  @NotNull private final Wrapper myToolbarStatusPanel;
+
+  @NotNull private final MergeRequest myRequest;
+  @NotNull private final MergeTool.MergeViewer myViewer;
+
+  @Nullable private BooleanGetter myCloseHandler;
+  private boolean myConflictResolved = false;
+
+  public MergeRequestProcessor(@Nullable Project project, @NotNull MergeRequest request) {
+    myProject = project;
+    myRequest = request;
+
+    myContext = new MyDiffContext();
+    myContext.putUserData(DiffUserDataKeysEx.PLACE, DiffPlaces.MERGE);
+
+    myAvailableTools = DiffManagerEx.getInstance().getMergeTools();
+
+    myPanel = new JPanel(new BorderLayout());
+    myMainPanel = new MyPanel();
+    myContentPanel = new Wrapper();
+    myToolbarPanel = new Wrapper();
+    myToolbarPanel.setFocusable(true);
+    myToolbarStatusPanel = new Wrapper();
+
+    myPanel.add(myMainPanel, BorderLayout.CENTER);
+
+    JPanel topPanel = new JPanel(new BorderLayout());
+    topPanel.add(myToolbarPanel, BorderLayout.CENTER);
+    topPanel.add(myToolbarStatusPanel, BorderLayout.EAST);
+
+
+    myMainPanel.add(topPanel, BorderLayout.NORTH);
+    myMainPanel.add(myContentPanel, BorderLayout.CENTER);
+
+    myMainPanel.setFocusTraversalPolicyProvider(true);
+    myMainPanel.setFocusTraversalPolicy(new MyFocusTraversalPolicy());
+
+    MergeTool.MergeViewer viewer;
+    try {
+      MergeTool tool = getFittedTool();
+      viewer = tool.createComponent(myContext, myRequest);
+    }
+    catch (Throwable e) {
+      LOG.error(e);
+      viewer = ErrorMergeTool.INSTANCE.createComponent(myContext, myRequest);
+    }
+    myViewer = viewer;
+  }
+
+  //
+  // Update
+  //
+
+  public void init() {
+    myContentPanel.setContent(myViewer.getComponent());
+    setTitle(myRequest.getTitle());
+
+    MergeTool.ToolbarComponents toolbarComponents = myViewer.init();
+
+    buildToolbar(toolbarComponents.toolbarActions);
+    myToolbarStatusPanel.setContent(toolbarComponents.statusPanel);
+    myCloseHandler = toolbarComponents.closeHandler;
+  }
+
+  @NotNull
+  public BottomActions getBottomActions() {
+    BottomActions actions = new BottomActions();
+    actions.applyLeft = myViewer.getResolveAction(MergeResult.LEFT);
+    actions.applyRight = myViewer.getResolveAction(MergeResult.RIGHT);
+    actions.resolveAction = myViewer.getResolveAction(MergeResult.RESOLVED);
+    actions.cancelAction = myViewer.getResolveAction(MergeResult.CANCEL);
+    return actions;
+  }
+
+  @NotNull
+  protected DefaultActionGroup collectToolbarActions(@Nullable List<AnAction> viewerActions) {
+    DefaultActionGroup group = new DefaultActionGroup();
+
+    List<AnAction> navigationActions = ContainerUtil.<AnAction>list(new MyPrevDifferenceAction(),
+                                                                    new MyNextDifferenceAction());
+    DiffUtil.addActionBlock(group, navigationActions);
+
+    DiffUtil.addActionBlock(group, viewerActions);
+
+    List<AnAction> requestContextActions = myRequest.getUserData(DiffUserDataKeys.CONTEXT_ACTIONS);
+    DiffUtil.addActionBlock(group, requestContextActions);
+
+    List<AnAction> contextActions = myContext.getUserData(DiffUserDataKeys.CONTEXT_ACTIONS);
+    DiffUtil.addActionBlock(group, contextActions);
+
+    return group;
+  }
+
+  protected void buildToolbar(@Nullable List<AnAction> viewerActions) {
+    ActionGroup group = collectToolbarActions(viewerActions);
+    ActionToolbar toolbar = ActionManager.getInstance().createActionToolbar(ActionPlaces.DIFF_TOOLBAR, group, true);
+
+    DataManager.registerDataProvider(toolbar.getComponent(), myMainPanel);
+    toolbar.setTargetComponent(toolbar.getComponent());
+
+    myToolbarPanel.setContent(toolbar.getComponent());
+    for (AnAction action : group.getChildren(null)) {
+      DiffUtil.registerAction(action, myMainPanel);
+    }
+  }
+
+  @NotNull
+  private MergeTool getFittedTool() {
+    for (MergeTool tool : myAvailableTools) {
+      try {
+        if (tool.canShow(myContext, myRequest)) return tool;
+      }
+      catch (Throwable e) {
+        LOG.error(e);
+      }
+    }
+
+    return ErrorMergeTool.INSTANCE;
+  }
+
+  private void setTitle(@Nullable String title) {
+    if (title == null) title = "Merge";
+    setWindowTitle(title);
+  }
+
+  @Override
+  public void dispose() {
+    if (myDisposed) return;
+    UIUtil.invokeLaterIfNeeded(new Runnable() {
+      @Override
+      public void run() {
+        if (myDisposed) return;
+        myDisposed = true;
+
+        onDispose();
+
+        Disposer.dispose(myViewer);
+
+        myToolbarStatusPanel.setContent(null);
+        myToolbarPanel.setContent(null);
+        myContentPanel.setContent(null);
+      }
+    });
+  }
+
+  @CalledInAwt
+  private void applyRequestResult(@NotNull MergeResult result) {
+    if (myConflictResolved) return;
+    myConflictResolved = true;
+    try {
+      myRequest.applyResult(result);
+    }
+    catch (Exception e) {
+      LOG.error(e);
+    }
+  }
+
+  //
+  // Abstract
+  //
+
+  @CalledInAwt
+  protected void onDispose() {
+    applyRequestResult(MergeResult.CANCEL);
+  }
+
+  protected void setWindowTitle(@NotNull String title) {
+  }
+
+  public abstract void closeDialog();
+
+  @Nullable
+  public <T> T getContextUserData(@NotNull Key<T> key) {
+    return myContext.getUserData(key);
+  }
+
+  public <T> void putContextUserData(@NotNull Key<T> key, @Nullable T value) {
+    myContext.putUserData(key, value);
+  }
+
+  //
+  // Getters
+  //
+
+  @NotNull
+  public JComponent getComponent() {
+    return myPanel;
+  }
+
+  @Nullable
+  public JComponent getPreferredFocusedComponent() {
+    JComponent component = myViewer.getPreferredFocusedComponent();
+    return component != null ? component : myToolbarPanel.getTargetComponent();
+  }
+
+  @Nullable
+  public Project getProject() {
+    return myProject;
+  }
+
+  @NotNull
+  public MergeContext getContext() {
+    return myContext;
+  }
+
+  @CalledInAwt
+  public boolean checkCloseAction() {
+    return myConflictResolved || myCloseHandler == null || myCloseHandler.get();
+  }
+
+  @Nullable
+  public String getHelpId() {
+    return PlatformDataKeys.HELP_ID.getData(myMainPanel);
+  }
+
+  //
+  // Misc
+  //
+
+  public boolean isFocused() {
+    return DiffUtil.isFocusedComponent(myProject, myPanel);
+  }
+
+  public void requestFocus() {
+    DiffUtil.requestFocus(myProject, getPreferredFocusedComponent());
+  }
+
+  protected void requestFocusInternal() {
+    JComponent component = getPreferredFocusedComponent();
+    if (component != null) component.requestFocus();
+  }
+
+  //
+  // Navigation
+  //
+
+  private static class MyNextDifferenceAction extends NextDifferenceAction {
+    @Override
+    public void update(@NotNull AnActionEvent e) {
+      if (!ActionPlaces.DIFF_TOOLBAR.equals(e.getPlace())) {
+        e.getPresentation().setEnabled(true);
+        return;
+      }
+
+      PrevNextDifferenceIterable iterable = DiffDataKeys.PREV_NEXT_DIFFERENCE_ITERABLE.getData(e.getDataContext());
+      if (iterable != null && iterable.canGoNext()) {
+        e.getPresentation().setEnabled(true);
+        return;
+      }
+
+      e.getPresentation().setEnabled(false);
+    }
+
+    @Override
+    public void actionPerformed(@NotNull AnActionEvent e) {
+      PrevNextDifferenceIterable iterable = DiffDataKeys.PREV_NEXT_DIFFERENCE_ITERABLE.getData(e.getDataContext());
+      if (iterable != null && iterable.canGoNext()) {
+        iterable.goNext();
+      }
+    }
+  }
+
+  private static class MyPrevDifferenceAction extends PrevDifferenceAction {
+    @Override
+    public void update(@NotNull AnActionEvent e) {
+      if (!ActionPlaces.DIFF_TOOLBAR.equals(e.getPlace())) {
+        e.getPresentation().setEnabled(true);
+        return;
+      }
+
+      PrevNextDifferenceIterable iterable = DiffDataKeys.PREV_NEXT_DIFFERENCE_ITERABLE.getData(e.getDataContext());
+      if (iterable != null && iterable.canGoPrev()) {
+        e.getPresentation().setEnabled(true);
+        return;
+      }
+
+      e.getPresentation().setEnabled(false);
+    }
+
+    @Override
+    public void actionPerformed(@NotNull AnActionEvent e) {
+      PrevNextDifferenceIterable iterable = DiffDataKeys.PREV_NEXT_DIFFERENCE_ITERABLE.getData(e.getDataContext());
+      if (iterable != null && iterable.canGoPrev()) {
+        iterable.goPrev();
+      }
+    }
+  }
+
+  //
+  // Helpers
+  //
+
+  private class MyPanel extends JPanel implements DataProvider {
+    public MyPanel() {
+      super(new BorderLayout());
+    }
+
+    @Nullable
+    @Override
+    public Object getData(@NonNls String dataId) {
+      Object data;
+
+      DataProvider contentProvider = DataManagerImpl.getDataProviderEx(myContentPanel.getTargetComponent());
+      if (contentProvider != null) {
+        data = contentProvider.getData(dataId);
+        if (data != null) return data;
+      }
+
+      if (CommonDataKeys.PROJECT.is(dataId)) {
+        return myProject;
+      }
+      else if (PlatformDataKeys.HELP_ID.is(dataId)) {
+        if (myRequest.getUserData(DiffUserDataKeys.HELP_ID) != null) {
+          return myRequest.getUserData(DiffUserDataKeys.HELP_ID);
+        }
+        else {
+          return "procedures.vcWithIDEA.commonVcsOps.integrateDiffs.resolveConflict";
+        }
+      }
+
+      DataProvider requestProvider = myRequest.getUserData(DiffUserDataKeys.DATA_PROVIDER);
+      if (requestProvider != null) {
+        data = requestProvider.getData(dataId);
+        if (data != null) return data;
+      }
+
+      DataProvider contextProvider = myContext.getUserData(DiffUserDataKeys.DATA_PROVIDER);
+      if (contextProvider != null) {
+        data = contextProvider.getData(dataId);
+        if (data != null) return data;
+      }
+      return null;
+    }
+  }
+
+  private class MyFocusTraversalPolicy extends IdeFocusTraversalPolicy {
+    @Override
+    public final Component getDefaultComponentImpl(final Container focusCycleRoot) {
+      JComponent component = MergeRequestProcessor.this.getPreferredFocusedComponent();
+      if (component == null) return null;
+      return IdeFocusTraversalPolicy.getPreferredFocusedComponent(component, this);
+    }
+  }
+
+  private class MyDiffContext extends MergeContext {
+    @Nullable
+    @Override
+    public Project getProject() {
+      return MergeRequestProcessor.this.getProject();
+    }
+
+    @Override
+    public boolean isFocused() {
+      return MergeRequestProcessor.this.isFocused();
+    }
+
+    @Override
+    public void requestFocus() {
+      MergeRequestProcessor.this.requestFocusInternal();
+    }
+
+    @Override
+    public void finishMerge(@NotNull MergeResult result) {
+      applyRequestResult(result);
+      MergeRequestProcessor.this.closeDialog();
+    }
+  }
+
+  public static class BottomActions {
+    @Nullable public Action applyLeft;
+    @Nullable public Action applyRight;
+    @Nullable public Action resolveAction;
+    @Nullable public Action cancelAction;
+  }
+}

platform/diff-impl/src/com/intellij/diff/merge/MergeUtil.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.DiffContext;
+import com.intellij.diff.util.ThreeSide;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.Key;
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.util.containers.ContainerUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+
+public class MergeUtil {
+  @NotNull
+  public static String getResolveActionTitle(@NotNull MergeResult result, @NotNull MergeRequest request, @NotNull MergeContext context) {
+    switch (result) {
+      case CANCEL:
+        return "Abort";
+      case LEFT:
+        return "Accept Left";
+      case RIGHT:
+        return "Accept Right";
+      case RESOLVED:
+        return "Apply";
+      default:
+        throw new IllegalArgumentException(result.toString());
+    }
+  }
+
+  @NotNull
+  public static List<String> notNullizeContentTitles(@NotNull List<String> mergeContentTitles) {
+    String left = StringUtil.notNullize(ThreeSide.LEFT.select(mergeContentTitles), "Your Version");
+    String base = StringUtil.notNullize(ThreeSide.BASE.select(mergeContentTitles), "Base Version");
+    String right = StringUtil.notNullize(ThreeSide.RIGHT.select(mergeContentTitles), "Server Version");
+    return ContainerUtil.list(left, base, right);
+  }
+
+  public static class ProxyDiffContext extends DiffContext {
+    @NotNull private final MergeContext myMergeContext;
+
+    public ProxyDiffContext(@NotNull MergeContext mergeContext) {
+      myMergeContext = mergeContext;
+    }
+
+    @Nullable
+    @Override
+    public Project getProject() {
+      return myMergeContext.getProject();
+    }
+
+    @Override
+    public boolean isWindowFocused() {
+      return true;
+    }
+
+    @Override
+    public boolean isFocused() {
+      return myMergeContext.isFocused();
+    }
+
+    @Override
+    public void requestFocus() {
+      myMergeContext.requestFocus();
+    }
+
+    @Nullable
+    @Override
+    public <T> T getUserData(@NotNull Key<T> key) {
+      return myMergeContext.getUserData(key);
+    }
+
+    @Override
+    public <T> void putUserData(@NotNull Key<T> key, @Nullable T value) {
+      myMergeContext.putUserData(key, value);
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/merge/MergeWindow.java

@@ -0,0 +1,165 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.util.DiffUserDataKeys;
+import com.intellij.diff.util.DiffUtil;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.ui.DialogWrapper;
+import com.intellij.openapi.util.Disposer;
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.util.containers.ContainerUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.WindowAdapter;
+import java.awt.event.WindowEvent;
+import java.util.List;
+
+public class MergeWindow {
+  @Nullable private final Project myProject;
+  @NotNull private final MergeRequest myMergeRequest;
+
+  private MyDialog myWrapper;
+
+  public MergeWindow(@Nullable Project project, @NotNull MergeRequest mergeRequest) {
+    myProject = project;
+    myMergeRequest = mergeRequest;
+  }
+
+  protected void init() {
+    MergeRequestProcessor processor = new MergeRequestProcessor(myProject, myMergeRequest) {
+      @Override
+      public void closeDialog() {
+        myWrapper.doCancelAction();
+      }
+
+      @Override
+      protected void setWindowTitle(@NotNull String title) {
+        myWrapper.setTitle(title);
+      }
+    };
+
+    myWrapper = new MyDialog(processor);
+    myWrapper.init();
+  }
+
+  public void show() {
+    init();
+    myWrapper.show();
+  }
+
+  // TODO: use WindowWrapper
+  private static class MyDialog extends DialogWrapper {
+    @NotNull private final MergeRequestProcessor myProcessor;
+    @NotNull private final MergeRequestProcessor.BottomActions myBottomActions;
+
+    public MyDialog(@NotNull MergeRequestProcessor processor) {
+      super(processor.getProject(), true);
+      myProcessor = processor;
+      myBottomActions = myProcessor.getBottomActions();
+    }
+
+    @Override
+    public void init() {
+      super.init();
+      Disposer.register(getDisposable(), myProcessor);
+      getWindow().addWindowListener(new WindowAdapter() {
+        @Override
+        public void windowOpened(WindowEvent e) {
+          myProcessor.init();
+        }
+      });
+    }
+
+    @Nullable
+    @Override
+    protected JComponent createCenterPanel() {
+      return new MyPanel(myProcessor.getComponent());
+    }
+
+    @Nullable
+    @Override
+    public JComponent getPreferredFocusedComponent() {
+      return myProcessor.getPreferredFocusedComponent();
+    }
+
+    @Nullable
+    @Override
+    protected String getDimensionServiceKey() {
+      return StringUtil.notNullize(myProcessor.getContextUserData(DiffUserDataKeys.DIALOG_GROUP_KEY), "MergeDialog");
+    }
+
+    @NotNull
+    @Override
+    protected Action[] createActions() {
+      List<Action> actions = ContainerUtil.skipNulls(ContainerUtil.list(myBottomActions.resolveAction, myBottomActions.cancelAction));
+      if (myBottomActions.resolveAction != null) {
+        myBottomActions.resolveAction.putValue(DialogWrapper.DEFAULT_ACTION, true);
+      }
+      return actions.toArray(new Action[actions.size()]);
+    }
+
+    @NotNull
+    @Override
+    protected Action[] createLeftSideActions() {
+      List<Action> actions = ContainerUtil.skipNulls(ContainerUtil.list(myBottomActions.applyLeft, myBottomActions.applyRight));
+      return actions.toArray(new Action[actions.size()]);
+    }
+
+    @NotNull
+    @Override
+    protected Action getOKAction() {
+      if (myBottomActions.resolveAction != null) return myBottomActions.resolveAction;
+      return super.getOKAction();
+    }
+
+    @NotNull
+    @Override
+    protected Action getCancelAction() {
+      if (myBottomActions.cancelAction != null) return myBottomActions.cancelAction;
+      return super.getCancelAction();
+    }
+
+    @Nullable
+    @Override
+    protected String getHelpId() {
+      return myProcessor.getHelpId();
+    }
+
+    @Override
+    public void doCancelAction() {
+      if (!myProcessor.checkCloseAction()) return;
+      super.doCancelAction();
+    }
+  }
+
+  private static class MyPanel extends JPanel {
+    public MyPanel(@NotNull JComponent content) {
+      super(new BorderLayout());
+      add(content, BorderLayout.CENTER);
+    }
+
+    @Override
+    public Dimension getPreferredSize() {
+      Dimension windowSize = DiffUtil.getDefaultDiffWindowSize();
+      Dimension size = super.getPreferredSize();
+      return new Dimension(Math.max(windowSize.width, size.width), Math.max(windowSize.height, size.height));
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/merge/TextMergeChange.java

@@ -0,0 +1,455 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.merge;
+
+import com.intellij.diff.comparison.ComparisonPolicy;
+import com.intellij.diff.fragments.MergeLineFragment;
+import com.intellij.diff.tools.simple.ThreesideDiffChangeBase;
+import com.intellij.diff.util.*;
+import com.intellij.diff.util.DiffUtil.UpdatedLineRange;
+import com.intellij.icons.AllIcons;
+import com.intellij.openapi.actionSystem.AnAction;
+import com.intellij.openapi.actionSystem.AnActionEvent;
+import com.intellij.openapi.diff.DiffBundle;
+import com.intellij.openapi.editor.Document;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.editor.ex.EditorEx;
+import com.intellij.openapi.editor.markup.*;
+import com.intellij.openapi.project.DumbAwareAction;
+import com.intellij.util.containers.ContainerUtil;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+public class TextMergeChange extends ThreesideDiffChangeBase {
+  @NotNull private final TextMergeTool.TextMergeViewer myMergeViewer;
+  @NotNull private final TextMergeTool.TextMergeViewer.MyThreesideViewer myViewer;
+  @NotNull private final List<RangeHighlighter> myHighlighters = new ArrayList<RangeHighlighter>();
+
+  @NotNull private final List<MyGutterOperation> myOperations = new ArrayList<MyGutterOperation>();
+
+  private final int[] myStartLines = new int[3];
+  private final int[] myEndLines = new int[3];
+  private final boolean[] myResolved = new boolean[2];
+  private boolean myOnesideAppliedConflict;
+
+  @CalledInAwt
+  public TextMergeChange(@NotNull MergeLineFragment fragment, @NotNull TextMergeTool.TextMergeViewer viewer) {
+    super(fragment, viewer.getViewer().getEditors(), ComparisonPolicy.DEFAULT);
+    myMergeViewer = viewer;
+    myViewer = viewer.getViewer();
+
+    for (ThreeSide side : ThreeSide.values()) {
+      myStartLines[side.getIndex()] = fragment.getStartLine(side);
+      myEndLines[side.getIndex()] = fragment.getEndLine(side);
+    }
+
+    installHighlighter();
+  }
+
+  void installHighlighter() {
+    assert myHighlighters.isEmpty();
+
+    createHighlighter(ThreeSide.BASE);
+    if (getType().isLeftChange()) createHighlighter(ThreeSide.LEFT);
+    if (getType().isRightChange()) createHighlighter(ThreeSide.RIGHT);
+
+    doInstallActionHighlighters();
+  }
+
+  @CalledInAwt
+  void destroyHighlighter() {
+    for (RangeHighlighter highlighter : myHighlighters) {
+      highlighter.dispose();
+    }
+    myHighlighters.clear();
+
+    for (MyGutterOperation operation : myOperations) {
+      operation.dispose();
+    }
+    myOperations.clear();
+  }
+
+  @CalledInAwt
+  void doReinstallHighlighter() {
+    destroyHighlighter();
+    installHighlighter();
+    myViewer.repaintDividers();
+  }
+
+  private void createHighlighter(@NotNull ThreeSide side) {
+    Editor editor = side.select(myViewer.getEditors());
+    Document document = editor.getDocument();
+
+    TextDiffType type = getDiffType();
+    boolean resolved = isResolved(side);
+    int startLine = getStartLine(side);
+    int endLine = getEndLine(side);
+
+    int start;
+    int end;
+    if (startLine == endLine) {
+      start = end = startLine < DiffUtil.getLineCount(document) ? document.getLineStartOffset(startLine) : document.getTextLength();
+    }
+    else {
+      start = document.getLineStartOffset(startLine);
+      end = document.getLineEndOffset(endLine - 1);
+      if (end < document.getTextLength()) end++;
+    }
+
+    myHighlighters.addAll(DiffDrawUtil.createHighlighter(editor, start, end, type, false, HighlighterTargetArea.EXACT_RANGE, resolved));
+
+    if (startLine == endLine) {
+      if (startLine != 0) {
+        myHighlighters.addAll(DiffDrawUtil.createLineMarker(editor, endLine - 1, type, SeparatorPlacement.BOTTOM, true, resolved));
+      }
+    }
+    else {
+      myHighlighters.addAll(DiffDrawUtil.createLineMarker(editor, startLine, type, SeparatorPlacement.TOP, false, resolved));
+      myHighlighters.addAll(DiffDrawUtil.createLineMarker(editor, endLine - 1, type, SeparatorPlacement.BOTTOM, false, resolved));
+    }
+  }
+
+  //
+  // Getters
+  //
+
+  @CalledInAwt
+  void setResolved(@NotNull Side side, boolean value) {
+    myResolved[side.getIndex()] = value;
+  }
+
+  public boolean isResolved() {
+    return myResolved[0] && myResolved[1];
+  }
+
+  public boolean isResolved(@NotNull Side side) {
+    return side.select(myResolved);
+  }
+
+  public boolean isOnesideAppliedConflict() {
+    return myOnesideAppliedConflict;
+  }
+
+  public void markOnesideAppliedConflict() {
+    myOnesideAppliedConflict = true;
+  }
+
+  public boolean isResolved(@NotNull ThreeSide side) {
+    switch (side) {
+      case LEFT:
+        return isResolved(Side.LEFT);
+      case BASE:
+        return isResolved();
+      case RIGHT:
+        return isResolved(Side.RIGHT);
+      default:
+        throw new IllegalArgumentException(side.toString());
+    }
+  }
+
+  public int getStartLine(@NotNull ThreeSide side) {
+    return side.select(myStartLines);
+  }
+
+  public int getEndLine(@NotNull ThreeSide side) {
+    return side.select(myEndLines);
+  }
+
+  public void setStartLine(@NotNull ThreeSide side, int value) {
+    myStartLines[side.getIndex()] = value;
+  }
+
+  public void setEndLine(@NotNull ThreeSide side, int value) {
+    myEndLines[side.getIndex()] = value;
+  }
+
+  //
+  // Shift
+  //
+
+  @Nullable
+  State processBaseChange(int oldLine1, int oldLine2, int shift) {
+    int line1 = getStartLine(ThreeSide.BASE);
+    int line2 = getEndLine(ThreeSide.BASE);
+
+    UpdatedLineRange newRange = DiffUtil.updateRangeOnModification(line1, line2, oldLine1, oldLine2, shift);
+
+    boolean rangeAffected = newRange.damaged ||
+                            (oldLine2 >= line1 && oldLine1 <= line2); // RangeMarker can be updated in a different way
+    State oldState = rangeAffected ? storeState() : null;
+
+    if (newRange.startLine == newRange.endLine && getDiffType() == TextDiffType.DELETED && !isResolved()) {
+      if (oldState == null) oldState = storeState();
+      myViewer.markChangeResolved(this);
+    }
+
+    setStartLine(ThreeSide.BASE, newRange.startLine);
+    setEndLine(ThreeSide.BASE, newRange.endLine);
+
+    return oldState;
+  }
+
+  //
+  // Gutter actions
+  //
+
+  private void doInstallActionHighlighters() {
+    ContainerUtil.addIfNotNull(myOperations, createOperation(ThreeSide.LEFT, OperationType.APPLY));
+    ContainerUtil.addIfNotNull(myOperations, createOperation(ThreeSide.LEFT, OperationType.IGNORE));
+    ContainerUtil.addIfNotNull(myOperations, createOperation(ThreeSide.RIGHT, OperationType.APPLY));
+    ContainerUtil.addIfNotNull(myOperations, createOperation(ThreeSide.RIGHT, OperationType.IGNORE));
+  }
+
+  @Nullable
+  private MyGutterOperation createOperation(@NotNull ThreeSide side, @NotNull OperationType type) {
+    if (isResolved(side)) return null;
+
+    EditorEx editor = myViewer.getEditor(side);
+    Document document = editor.getDocument();
+
+    int line = getStartLine(side);
+    int offset = line == DiffUtil.getLineCount(document) ? document.getTextLength() : document.getLineStartOffset(line);
+
+    RangeHighlighter highlighter = editor.getMarkupModel().addRangeHighlighter(offset, offset,
+                                                                               HighlighterLayer.ADDITIONAL_SYNTAX,
+                                                                               null,
+                                                                               HighlighterTargetArea.LINES_IN_RANGE);
+    return new MyGutterOperation(side, highlighter, type);
+  }
+
+  public void updateGutterActions(boolean force) {
+    for (MyGutterOperation operation : myOperations) {
+      operation.update(force);
+    }
+  }
+
+  private class MyGutterOperation {
+    @NotNull private final ThreeSide mySide;
+    @NotNull private final RangeHighlighter myHighlighter;
+    @NotNull private final OperationType myType;
+
+    private boolean myCtrlPressed;
+    private boolean myShiftPressed;
+
+    private MyGutterOperation(@NotNull ThreeSide side, @NotNull RangeHighlighter highlighter, @NotNull OperationType type) {
+      mySide = side;
+      myHighlighter = highlighter;
+      myType = type;
+
+      update(true);
+    }
+
+    public void dispose() {
+      myHighlighter.dispose();
+    }
+
+    public void update(boolean force) {
+      if (!force && !areModifiersChanged()) {
+        return;
+      }
+      if (myHighlighter.isValid()) myHighlighter.setGutterIconRenderer(createRenderer());
+    }
+
+    private boolean areModifiersChanged() {
+      return myCtrlPressed != myViewer.getModifierProvider().isCtrlPressed() ||
+             myShiftPressed != myViewer.getModifierProvider().isShiftPressed();
+    }
+
+    @Nullable
+    public GutterIconRenderer createRenderer() {
+      if (mySide == ThreeSide.BASE) return null;
+      Side versionSide = mySide.select(Side.LEFT, null, Side.RIGHT);
+      assert versionSide != null;
+
+      myCtrlPressed = myViewer.getModifierProvider().isCtrlPressed();
+      myShiftPressed = myViewer.getModifierProvider().isShiftPressed();
+
+      if (!isChange(versionSide)) return null;
+
+      switch (myType) {
+        case APPLY:
+          return createApplyRenderer(versionSide, myCtrlPressed);
+        case IGNORE:
+          return createIgnoreRenderer(versionSide, myCtrlPressed);
+        default:
+          throw new IllegalArgumentException(myType.name());
+      }
+    }
+  }
+
+  @Nullable
+  private GutterIconRenderer createApplyRenderer(@NotNull final Side side, final boolean modifier) {
+    if (isResolved(side)) return null;
+    Icon icon = isOnesideAppliedConflict() ? AllIcons.Diff.ArrowLeftDown : AllIcons.Diff.Arrow;
+    return createIconRenderer(DiffBundle.message("merge.dialog.apply.change.action.name"), icon, new Runnable() {
+      @Override
+      public void run() {
+        myViewer.executeMergeCommand("Apply change", Collections.singletonList(TextMergeChange.this), new Runnable() {
+          @Override
+          public void run() {
+            myViewer.replaceChange(TextMergeChange.this, side, modifier);
+          }
+        });
+      }
+    });
+  }
+
+  @Nullable
+  private GutterIconRenderer createIgnoreRenderer(@NotNull final Side side, final boolean modifier) {
+    if (isResolved(side)) return null;
+    return createIconRenderer(DiffBundle.message("merge.dialog.ignore.change.action.name"), AllIcons.Diff.Remove, new Runnable() {
+      @Override
+      public void run() {
+        myViewer.executeMergeCommand(null, Collections.singletonList(TextMergeChange.this), new Runnable() {
+          @Override
+          public void run() {
+            myViewer.ignoreChange(TextMergeChange.this, side, modifier);
+          }
+        });
+      }
+    });
+  }
+
+  @Nullable
+  private GutterIconRenderer createIconRenderer(@NotNull final String tooltipText,
+                                                @NotNull final Icon icon,
+                                                @NotNull final Runnable perform) {
+    return new GutterIconRenderer() {
+      @NotNull
+      @Override
+      public Icon getIcon() {
+        return icon;
+      }
+
+      public boolean isNavigateAction() {
+        return true;
+      }
+
+      @Nullable
+      @Override
+      public AnAction getClickAction() {
+        return new DumbAwareAction() {
+          @Override
+          public void actionPerformed(AnActionEvent e) {
+            perform.run();
+          }
+        };
+      }
+
+      @Override
+      public boolean equals(Object obj) {
+        return obj == this;
+      }
+
+      @Override
+      public int hashCode() {
+        return System.identityHashCode(this);
+      }
+
+      @Nullable
+      @Override
+      public String getTooltipText() {
+        return tooltipText;
+      }
+
+      @Override
+      public boolean isDumbAware() {
+        return true;
+      }
+    };
+  }
+
+  private enum OperationType {
+    APPLY, IGNORE
+  }
+
+  //
+  // State
+  //
+
+  @NotNull
+  State storeState() {
+    return new State(
+      myStartLines[0],
+      myStartLines[1],
+      myStartLines[2],
+
+      myEndLines[0],
+      myEndLines[1],
+      myEndLines[2],
+
+      myResolved[0],
+      myResolved[1],
+
+      myOnesideAppliedConflict);
+  }
+
+  void restoreState(@NotNull State state) {
+    myStartLines[0] = state.myStartLine1;
+    myStartLines[1] = state.myStartLine2;
+    myStartLines[2] = state.myStartLine3;
+
+    myEndLines[0] = state.myEndLine1;
+    myEndLines[1] = state.myEndLine2;
+    myEndLines[2] = state.myEndLine3;
+
+    myResolved[0] = state.myResolved1;
+    myResolved[1] = state.myResolved2;
+
+    myOnesideAppliedConflict = state.myOnesideAppliedConflict;
+  }
+
+  public static class State {
+    private final int myStartLine1;
+    private final int myStartLine2;
+    private final int myStartLine3;
+
+    private final int myEndLine1;
+    private final int myEndLine2;
+    private final int myEndLine3;
+
+    private final boolean myResolved1;
+    private final boolean myResolved2;
+
+    private final boolean myOnesideAppliedConflict;
+
+    public State(int startLine1,
+                 int startLine2,
+                 int startLine3,
+                 int endLine1,
+                 int endLine2,
+                 int endLine3,
+                 boolean resolved1,
+                 boolean resolved2,
+                 boolean onesideAppliedConflict) {
+      myStartLine1 = startLine1;
+      myStartLine2 = startLine2;
+      myStartLine3 = startLine3;
+      myEndLine1 = endLine1;
+      myEndLine2 = endLine2;
+      myEndLine3 = endLine3;
+      myResolved1 = resolved1;
+      myResolved2 = resolved2;
+      myOnesideAppliedConflict = onesideAppliedConflict;
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/requests/BinaryMergeRequestImpl.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.requests;
+
+import com.intellij.CommonBundle;
+import com.intellij.diff.contents.DiffContent;
+import com.intellij.diff.contents.FileContent;
+import com.intellij.diff.merge.ThreesideMergeRequest;
+import com.intellij.diff.merge.MergeResult;
+import com.intellij.diff.util.ThreeSide;
+import com.intellij.openapi.command.WriteCommandAction;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.ui.Messages;
+import com.intellij.util.Consumer;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.IOException;
+import java.util.List;
+
+public class BinaryMergeRequestImpl extends ThreesideMergeRequest {
+  private static final Logger LOG = Logger.getInstance(BinaryMergeRequestImpl.class);
+
+  @NotNull private final FileContent myFile;
+  @NotNull private final List<DiffContent> myContents;
+
+  @NotNull private final List<byte[]> myByteContents;
+  @NotNull private final byte[] myOriginalContent;
+
+  @Nullable private final String myTitle;
+  @NotNull private final List<String> myTitles;
+
+  @Nullable private final Consumer<MergeResult> myApplyCallback;
+
+  public BinaryMergeRequestImpl(@NotNull FileContent file,
+                                @NotNull byte[] originalContent,
+                                @NotNull List<DiffContent> contents,
+                                @NotNull List<byte[]> byteContents,
+                                @Nullable String title,
+                                @NotNull List<String> contentTitles,
+                                @Nullable Consumer<MergeResult> applyCallback) {
+    assert byteContents.size() == 3;
+    assert contents.size() == 3;
+    assert contentTitles.size() == 3;
+
+    myFile = file;
+    myOriginalContent = originalContent;
+
+    myByteContents = byteContents;
+    myContents = contents;
+    myTitle = title;
+    myTitles = contentTitles;
+
+    myApplyCallback = applyCallback;
+  }
+
+  @NotNull
+  @Override
+  public FileContent getOutputContent() {
+    return myFile;
+  }
+
+  @NotNull
+  @Override
+  public List<DiffContent> getContents() {
+    return myContents;
+  }
+
+  @Nullable
+  @Override
+  public String getTitle() {
+    return myTitle;
+  }
+
+  @NotNull
+  @Override
+  public List<String> getContentTitles() {
+    return myTitles;
+  }
+
+  @Override
+  public void applyResult(@NotNull MergeResult result) {
+    final byte[] applyContent;
+    switch (result) {
+      case CANCEL:
+        applyContent = myOriginalContent;
+        break;
+      case LEFT:
+        applyContent = ThreeSide.LEFT.select(myByteContents);
+        break;
+      case RIGHT:
+        applyContent = ThreeSide.RIGHT.select(myByteContents);
+        break;
+      case RESOLVED:
+        applyContent = null;
+        break;
+      default:
+        throw new IllegalArgumentException(result.toString());
+    }
+
+    if (applyContent != null) {
+      new WriteCommandAction.Simple(null) {
+        @Override
+        protected void run() throws Throwable {
+          try {
+            myFile.getFile().setBinaryContent(applyContent);
+          }
+          catch (IOException e) {
+            LOG.error(e);
+            Messages.showErrorDialog((Project)null, "Can't apply result", CommonBundle.getErrorTitle());
+          }
+        }
+      }.execute();
+    }
+
+    if (myApplyCallback != null) myApplyCallback.consume(result);
+  }
+}

platform/diff-impl/src/com/intellij/diff/requests/TextMergeRequestImpl.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.requests;
+
+import com.intellij.diff.contents.DocumentContent;
+import com.intellij.diff.merge.MergeResult;
+import com.intellij.diff.merge.TextMergeRequest;
+import com.intellij.diff.util.ThreeSide;
+import com.intellij.openapi.command.WriteCommandAction;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.util.Consumer;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+
+public class TextMergeRequestImpl extends TextMergeRequest {
+  @Nullable private final Project myProject;
+  @NotNull private final DocumentContent myOutput;
+  @NotNull private final List<DocumentContent> myContents;
+
+  @NotNull private final CharSequence myOriginalContent;
+
+  @Nullable private final String myTitle;
+  @NotNull private final List<String> myTitles;
+
+  @Nullable private final Consumer<MergeResult> myApplyCallback;
+
+  public TextMergeRequestImpl(@Nullable Project project,
+                              @NotNull DocumentContent output,
+                              @NotNull CharSequence originalContent,
+                              @NotNull List<DocumentContent> contents,
+                              @Nullable String title,
+                              @NotNull List<String> contentTitles,
+                              @Nullable Consumer<MergeResult> applyCallback) {
+    assert contents.size() == 3;
+    assert contentTitles.size() == 3;
+    myProject = project;
+
+    myOutput = output;
+    myOriginalContent = originalContent;
+
+    myContents = contents;
+    myTitles = contentTitles;
+    myTitle = title;
+
+    myApplyCallback = applyCallback;
+  }
+
+  @NotNull
+  @Override
+  public DocumentContent getOutputContent() {
+    return myOutput;
+  }
+
+  @NotNull
+  @Override
+  public List<DocumentContent> getContents() {
+    return myContents;
+  }
+
+  @Nullable
+  @Override
+  public String getTitle() {
+    return myTitle;
+  }
+
+  @NotNull
+  @Override
+  public List<String> getContentTitles() {
+    return myTitles;
+  }
+
+  @Override
+  public void applyResult(@NotNull MergeResult result) {
+    final CharSequence applyContent;
+    switch (result) {
+      case CANCEL:
+        applyContent = myOriginalContent;
+        break;
+      case LEFT:
+        CharSequence leftContent = ThreeSide.LEFT.select(getContents()).getDocument().getImmutableCharSequence();
+        applyContent = StringUtil.convertLineSeparators(leftContent.toString());
+        break;
+      case RIGHT:
+        CharSequence rightContent = ThreeSide.RIGHT.select(getContents()).getDocument().getImmutableCharSequence();
+        applyContent = StringUtil.convertLineSeparators(rightContent.toString());
+        break;
+      case RESOLVED:
+        applyContent = null;
+        break;
+      default:
+        throw new IllegalArgumentException(result.toString());
+    }
+
+    if (applyContent != null) {
+      new WriteCommandAction.Simple(myProject) {
+        @Override
+        protected void run() throws Throwable {
+          myOutput.getDocument().setText(applyContent);
+        }
+      }.execute();
+    }
+
+    if (myApplyCallback != null) myApplyCallback.consume(result);
+  }
+}

platform/diff-impl/src/com/intellij/diff/requests/UnknownFileTypeDiffRequest.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.requests;
+
+import com.intellij.diff.DiffContext;
+import com.intellij.diff.DiffContextEx;
+import com.intellij.diff.util.DiffUtil;
+import com.intellij.openapi.fileTypes.FileType;
+import com.intellij.openapi.fileTypes.FileTypeManager;
+import com.intellij.openapi.fileTypes.UnknownFileType;
+import com.intellij.openapi.fileTypes.ex.FileTypeChooser;
+import com.intellij.openapi.vcs.changes.issueLinks.LinkMouseListenerBase;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.ui.SimpleColoredComponent;
+import com.intellij.ui.SimpleTextAttributes;
+import com.intellij.util.ui.UIUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+
+public class UnknownFileTypeDiffRequest extends ComponentDiffRequest {
+  @Nullable private final String myFileName;
+  @Nullable private final String myTitle;
+
+  public UnknownFileTypeDiffRequest(@NotNull VirtualFile file, @Nullable String title) {
+    this(file.getName(), title);
+  }
+
+  public UnknownFileTypeDiffRequest(@NotNull String fileName, @Nullable String title) {
+    boolean knownFileType = FileTypeManager.getInstance().getFileTypeByFileName(fileName) != UnknownFileType.INSTANCE;
+    myFileName = knownFileType ? null : fileName;
+    myTitle = title;
+  }
+
+  public UnknownFileTypeDiffRequest(@Nullable String title) {
+    myFileName = null;
+    myTitle = title;
+  }
+
+  @NotNull
+  @Override
+  public JComponent getComponent(@NotNull final DiffContext context) {
+    final SimpleColoredComponent label = new SimpleColoredComponent();
+    label.append("Can't show diff for unknown file type. ",
+                 new SimpleTextAttributes(SimpleTextAttributes.STYLE_PLAIN, UIUtil.getInactiveTextColor()));
+    if (myFileName != null) {
+      label.append("Associate", SimpleTextAttributes.LINK_ATTRIBUTES, new Runnable() {
+        @Override
+        public void run() {
+          FileType type = FileTypeChooser.associateFileType(myFileName);
+          if (type != null) onSuccess(context);
+        }
+      });
+      LinkMouseListenerBase.installSingleTagOn(label);
+    }
+    return DiffUtil.createMessagePanel(label);
+  }
+
+  @Nullable
+  public String getFileName() {
+    return myFileName;
+  }
+
+  @Nullable
+  @Override
+  public String getTitle() {
+    return myTitle;
+  }
+
+  protected void onSuccess(@NotNull DiffContext context) {
+    if (context instanceof DiffContextEx) ((DiffContextEx)context).reloadDiffRequest();
+  }
+}

platform/diff-impl/src/com/intellij/diff/settings/DiffSettingsPaneExternall.form

@@ -84,7 +84,7 @@
           </component>
         </children>
       </grid>
-      <grid id="d5bc7" layout-manager="GridLayoutManager" row-count="1" column-count="2" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+      <grid id="d5bc7" layout-manager="GridLayoutManager" row-count="1" column-count="3" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
         <margin top="0" left="0" bottom="0" right="0"/>
         <constraints>
           <grid row="3" column="0" row-span="1" col-span="4" vsize-policy="3" hsize-policy="3" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
@@ -103,9 +103,18 @@
           </component>
           <hspacer id="3caba">
             <constraints>
-              <grid row="0" column="1" row-span="1" col-span="1" vsize-policy="1" hsize-policy="6" anchor="0" fill="1" indent="0" use-parent-layout="false"/>
+              <grid row="0" column="2" row-span="1" col-span="1" vsize-policy="1" hsize-policy="6" anchor="0" fill="1" indent="0" use-parent-layout="false"/>
             </constraints>
           </hspacer>
+          <component id="5eb41" class="javax.swing.JCheckBox" binding="myRespectExitCodeCheckbox">
+            <constraints>
+              <grid row="0" column="1" row-span="1" col-span="1" vsize-policy="0" hsize-policy="3" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <margin top="4" left="2" bottom="0" right="2"/>
+              <text value="Trust process exit code"/>
+            </properties>
+          </component>
         </children>
       </grid>
       <component id="7e9c5" class="javax.swing.JLabel">

platform/diff-impl/src/com/intellij/diff/settings/ExternalDiffSettingsPanel.java

@@ -50,6 +50,7 @@ public class ExternalDiffSettingsPanel {
   private TextFieldWithBrowseButton myMergePath;
   private JTextField myMergeParameters;
   private JLabel myDescriptionLabel;
+  private JCheckBox myRespectExitCodeCheckbox;
 
   public ExternalDiffSettingsPanel() {
     myDescriptionLabel.setText(DESCRIPTION_TEXT);
@@ -87,6 +88,7 @@ public class ExternalDiffSettingsPanel {
     if (mySettings.isMergeEnabled() != myMergeEnabled.isSelected()) return true;
     if (!mySettings.getMergeExePath().equals(myMergePath.getText())) return true;
     if (!mySettings.getMergeParameters().equals(myMergeParameters.getText())) return true;
+    if (mySettings.isMergeTrustExitCode() != myRespectExitCodeCheckbox.isSelected()) return true;
 
     return false;
   }
@@ -100,6 +102,7 @@ public class ExternalDiffSettingsPanel {
     mySettings.setMergeEnabled(myMergeEnabled.isSelected());
     mySettings.setMergeExePath(myMergePath.getText());
     mySettings.setMergeParameters(myMergeParameters.getText());
+    mySettings.setMergeTrustExitCode(myRespectExitCodeCheckbox.isSelected());
   }
 
   public void reset() {
@@ -111,6 +114,7 @@ public class ExternalDiffSettingsPanel {
     myMergePath.setText(mySettings.getMergeExePath());
     myMergeEnabled.setSelected(mySettings.isMergeEnabled());
     myMergeParameters.setText(mySettings.getMergeParameters());
+    myRespectExitCodeCheckbox.setSelected(mySettings.isMergeTrustExitCode());
 
     updateEnabledEffect();
   }
@@ -122,6 +126,7 @@ public class ExternalDiffSettingsPanel {
 
     UIUtil.setEnabled(myMergePath, myMergeEnabled.isSelected(), true);
     UIUtil.setEnabled(myMergeParameters, myMergeEnabled.isSelected(), true);
+    UIUtil.setEnabled(myRespectExitCodeCheckbox, myMergeEnabled.isSelected(), true);
   }
 
   private void createUIComponents() {

platform/diff-impl/src/com/intellij/diff/tools/ErrorDiffTool.java

@@ -20,19 +20,15 @@ import com.intellij.diff.DiffContextEx;
 import com.intellij.diff.FrameDiffTool;
 import com.intellij.diff.contents.DiffContent;
 import com.intellij.diff.contents.FileContent;
-import com.intellij.diff.requests.ContentDiffRequest;
-import com.intellij.diff.requests.DiffRequest;
-import com.intellij.diff.requests.MessageDiffRequest;
+import com.intellij.diff.requests.*;
 import com.intellij.diff.util.DiffUtil;
-import com.intellij.openapi.fileTypes.FileType;
+import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.application.ModalityState;
+import com.intellij.openapi.fileTypes.FileTypeManager;
 import com.intellij.openapi.fileTypes.FileTypes;
-import com.intellij.openapi.fileTypes.ex.FileTypeChooser;
-import com.intellij.openapi.vcs.changes.issueLinks.LinkMouseListenerBase;
+import com.intellij.openapi.fileTypes.UnknownFileType;
 import com.intellij.openapi.vfs.VirtualFile;
-import com.intellij.ui.SimpleColoredComponent;
-import com.intellij.ui.SimpleTextAttributes;
 import com.intellij.util.ui.JBUI;
-import com.intellij.util.ui.UIUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -79,26 +75,17 @@ public class ErrorDiffTool implements FrameDiffTool {
         String message = ((MessageDiffRequest)request).getMessage();
         return DiffUtil.createMessagePanel(message);
       }
+      if (request instanceof ComponentDiffRequest) {
+        return ((ComponentDiffRequest)request).getComponent(myContext);
+      }
       if (request instanceof ContentDiffRequest) {
         List<DiffContent> contents = ((ContentDiffRequest)request).getContents();
-        for (DiffContent content : contents) {
+        for (final DiffContent content : contents) {
           if (content instanceof FileContent && FileTypes.UNKNOWN.equals(content.getContentType())) {
             final VirtualFile file = ((FileContent)content).getFile();
 
-            final SimpleColoredComponent label = new SimpleColoredComponent();
-            label.append("Can't show diff for unknown file type. ",
-                         new SimpleTextAttributes(SimpleTextAttributes.STYLE_PLAIN, UIUtil.getInactiveTextColor()));
-            label.append("Associate", SimpleTextAttributes.LINK_ATTRIBUTES, new Runnable() {
-              @Override
-              public void run() {
-                FileType type = FileTypeChooser.associateFileType(file.getName());
-                if (type != null && myContext instanceof DiffContextEx) {
-                  ((DiffContextEx)myContext).reloadDiffRequest();
-                }
-              }
-            });
-            LinkMouseListenerBase.installSingleTagOn(label);
-            return DiffUtil.createMessagePanel(label);
+            UnknownFileTypeDiffRequest unknownFileTypeRequest = new UnknownFileTypeDiffRequest(file, myRequest.getTitle());
+            return unknownFileTypeRequest.getComponent(myContext);
           }
         }
       }
@@ -121,6 +108,21 @@ public class ErrorDiffTool implements FrameDiffTool {
     @NotNull
     @Override
     public ToolbarComponents init() {
+      if (myRequest instanceof UnknownFileTypeDiffRequest) {
+        String fileName = ((UnknownFileTypeDiffRequest)myRequest).getFileName();
+        if (fileName != null && FileTypeManager.getInstance().getFileTypeByFileName(fileName) != UnknownFileType.INSTANCE) {
+          // FileType was assigned elsewhere (ex: by other UnknownFileTypeDiffRequest). We should reload request.
+          if (myContext instanceof DiffContextEx) {
+            ApplicationManager.getApplication().invokeLater(new Runnable() {
+              @Override
+              public void run() {
+                ((DiffContextEx)myContext).reloadDiffRequest();
+              }
+            }, ModalityState.current());
+          }
+        }
+      }
+
       return new ToolbarComponents();
     }
 

platform/diff-impl/src/com/intellij/diff/tools/external/ExternalDiffSettings.java

@@ -91,6 +91,7 @@ public class ExternalDiffSettings implements PersistentStateComponent<ExternalDi
     @Nullable public Boolean MERGE_ENABLED = null;
     @Nullable public String MERGE_EXE_PATH = null;
     @Nullable public String MERGE_PARAMETERS = null;
+    public boolean MERGE_TRUST_EXIT_CODE = false;
   }
 
   public boolean isDiffEnabled() {
@@ -158,4 +159,12 @@ public class ExternalDiffSettings implements PersistentStateComponent<ExternalDi
     myState.MERGE_PARAMETERS = path;
     setProperty(DiffManagerImpl.MERGE_TOOL_PARAMETERS, path);
   }
+
+  public boolean isMergeTrustExitCode() {
+    return myState.MERGE_TRUST_EXIT_CODE;
+  }
+
+  public void setMergeTrustExitCode(boolean value) {
+    myState.MERGE_TRUST_EXIT_CODE = value;
+  }
 }

platform/diff-impl/src/com/intellij/diff/tools/external/ExternalDiffToolUtil.java

@@ -16,18 +16,28 @@
 package com.intellij.diff.tools.external;
 
 import com.intellij.diff.contents.*;
+import com.intellij.diff.merge.MergeResult;
+import com.intellij.diff.merge.ThreesideMergeRequest;
 import com.intellij.execution.ExecutionException;
 import com.intellij.execution.configurations.CommandLineTokenizer;
 import com.intellij.execution.configurations.GeneralCommandLine;
 import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
 import com.intellij.openapi.fileTypes.FileType;
+import com.intellij.openapi.progress.ProgressIndicator;
+import com.intellij.openapi.progress.ProgressManager;
+import com.intellij.openapi.progress.Task;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.ui.Messages;
 import com.intellij.openapi.util.Computable;
+import com.intellij.openapi.util.Ref;
 import com.intellij.openapi.util.io.FileUtil;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.util.LineSeparator;
 import com.intellij.util.PathUtil;
+import com.intellij.util.TimeoutUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -36,6 +46,8 @@ import java.io.IOException;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.Semaphore;
+import java.util.concurrent.TimeUnit;
 
 public class ExternalDiffToolUtil {
   public static boolean canCreateFile(@NotNull DiffContent content) {
@@ -59,31 +71,12 @@ public class ExternalDiffToolUtil {
         return file.getPath();
       }
 
-      byte[] bytes = file.contentsToByteArray();
-      return createFile(bytes, getFileName(title, windowTitle, content.getContentType())).getPath();
+      String tempFileName = getFileName(title, windowTitle, content.getContentType());
+      return createTempFile(file, tempFileName).getPath();
     }
     else if (content instanceof DocumentContent) {
-      final DocumentContent documentContent = (DocumentContent)content;
-      FileDocumentManager.getInstance().saveDocument(documentContent.getDocument());
-
-      LineSeparator separator = documentContent.getLineSeparator();
-      if (separator == null) separator = LineSeparator.getSystemLineSeparator();
-
-      Charset charset = documentContent.getCharset();
-      if (charset == null) charset = Charset.defaultCharset();
-
-      String contentData = ApplicationManager.getApplication().runReadAction(new Computable<String>() {
-        @Override
-        public String compute() {
-          return documentContent.getDocument().getText();
-        }
-      });
-      if (separator != LineSeparator.LF) {
-        contentData = StringUtil.convertLineSeparators(contentData, separator.getSeparatorString());
-      }
-
-      byte[] bytes = contentData.getBytes(charset);
-      return createFile(bytes, getFileName(title, windowTitle, content.getContentType())).getPath();
+      String tempFileName = getFileName(title, windowTitle, content.getContentType());
+      return createTempFile(((DocumentContent)content), tempFileName).getPath();
     }
     else if (content instanceof DirectoryContent) {
       VirtualFile file = ((DirectoryContent)content).getFile();
@@ -97,6 +90,56 @@ public class ExternalDiffToolUtil {
     throw new IllegalArgumentException(content.toString());
   }
 
+  @NotNull
+  private static File createTempFile(@NotNull final DocumentContent content, @NotNull String tempFileName) throws IOException {
+    FileDocumentManager.getInstance().saveDocument(content.getDocument());
+
+    LineSeparator separator = content.getLineSeparator();
+    if (separator == null) separator = LineSeparator.getSystemLineSeparator();
+
+    Charset charset = content.getCharset();
+    if (charset == null) charset = Charset.defaultCharset();
+
+    String contentData = ApplicationManager.getApplication().runReadAction(new Computable<String>() {
+      @Override
+      public String compute() {
+        return content.getDocument().getText();
+      }
+    });
+    if (separator != LineSeparator.LF) {
+      contentData = StringUtil.convertLineSeparators(contentData, separator.getSeparatorString());
+    }
+
+    byte[] bytes = contentData.getBytes(charset);
+    return createFile(bytes, tempFileName);
+  }
+
+  @NotNull
+  private static File createTempFile(@NotNull VirtualFile file, @NotNull String tempFileName) throws IOException {
+    byte[] bytes = file.contentsToByteArray();
+    return createFile(bytes, tempFileName);
+  }
+
+  @NotNull
+  public static OutputFile createOutputFile(@NotNull DiffContent content, @Nullable String windowTitle) throws IOException {
+    if (content instanceof FileContent) {
+      FileContent fileContent = (FileContent)content;
+      if (fileContent.getFile().isInLocalFileSystem()) {
+        return new LocalOutputFile(fileContent.getFile());
+      }
+
+      String tempFileName = getFileName(null, windowTitle, content.getContentType());
+      File tempFile = createTempFile(fileContent.getFile(), tempFileName);
+      return new NonLocalOutputFile(fileContent.getFile(), tempFile);
+    }
+    else if (content instanceof DocumentContent) {
+      String tempFileName = getFileName(null, windowTitle, content.getContentType());
+      File tempFile = createTempFile(((DocumentContent)content), tempFileName);
+      return new DocumentOutputFile(((DocumentContent)content).getDocument(), ((DocumentContent)content).getCharset(), tempFile);
+    }
+    throw new IllegalArgumentException(content.toString());
+  }
+
   @NotNull
   public static String getFileName(@Nullable String title, @Nullable String windowTitle, @Nullable FileType fileType) {
     String prefix = "";
@@ -120,7 +163,7 @@ public class ExternalDiffToolUtil {
   }
 
   public static void execute(@NotNull ExternalDiffSettings settings,
-                             @NotNull List<DiffContent> contents,
+                             @NotNull List<? extends DiffContent> contents,
                              @NotNull List<String> titles,
                              @Nullable String windowTitle)
     throws IOException, ExecutionException {
@@ -162,4 +205,194 @@ public class ExternalDiffToolUtil {
     commandLine.addParameters(args);
     commandLine.createProcess();
   }
+
+  public static void executeMerge(@Nullable Project project,
+                                  @NotNull ExternalDiffSettings settings,
+                                  @NotNull ThreesideMergeRequest request)
+    throws IOException, ExecutionException {
+    boolean success = false;
+    try {
+      DiffContent outputContent = request.getOutputContent();
+      List<? extends DiffContent> contents = request.getContents();
+      List<String> titles = request.getContentTitles();
+      String windowTitle = request.getTitle();
+
+      assert contents.size() == 3;
+      assert titles.size() == contents.size();
+
+      List<String> files = new ArrayList<String>();
+      for (int i = 0; i < contents.size(); i++) {
+        files.add(createFile(contents.get(i), titles.get(i), windowTitle));
+      }
+
+      OutputFile outputFile = createOutputFile(outputContent, windowTitle);
+
+      CommandLineTokenizer parameterTokenizer = new CommandLineTokenizer(settings.getMergeParameters(), true);
+
+      List<String> args = new ArrayList<String>();
+      while (parameterTokenizer.hasMoreTokens()) {
+        String arg = parameterTokenizer.nextToken();
+        if ("%1".equals(arg)) {
+          args.add(files.get(0));
+        }
+        else if ("%2".equals(arg)) {
+          args.add(files.get(2));
+        }
+        else if ("%3".equals(arg)) {
+          args.add(files.get(1));
+        }
+        else if ("%4".equals(arg)) {
+          args.add(outputFile.getPath());
+        }
+        else {
+          args.add(arg);
+        }
+      }
+
+      GeneralCommandLine commandLine = new GeneralCommandLine();
+      commandLine.setExePath(settings.getMergeExePath());
+
+      commandLine.addParameters(args);
+      final Process process = commandLine.createProcess();
+
+      if (settings.isMergeTrustExitCode()) {
+        final Ref<Boolean> resultRef = new Ref<Boolean>();
+
+        ProgressManager.getInstance().run(new Task.Modal(project, "Waiting for external tool", true) {
+          @Override
+          public void run(@NotNull ProgressIndicator indicator) {
+            final Semaphore semaphore = new Semaphore(0);
+
+            final Thread waiter = new Thread("external process waiter") {
+              @Override
+              public void run() {
+                try {
+                  resultRef.set(process.waitFor() == 0);
+                }
+                catch (InterruptedException ignore) {
+                }
+                finally {
+                  semaphore.release();
+                }
+              }
+            };
+            waiter.start();
+
+            try {
+              while (true) {
+                indicator.checkCanceled();
+                if (semaphore.tryAcquire(200, TimeUnit.MILLISECONDS)) break;
+              }
+            }
+            catch (InterruptedException ignore) {
+            }
+            finally {
+              waiter.interrupt();
+            }
+          }
+        });
+
+        success = resultRef.get() == Boolean.TRUE;
+      }
+      else {
+        ProgressManager.getInstance().run(new Task.Modal(project, "Launching external tool", false) {
+          @Override
+          public void run(@NotNull ProgressIndicator indicator) {
+            indicator.setIndeterminate(true);
+            TimeoutUtil.sleep(1000);
+          }
+        });
+
+        success = Messages.showYesNoDialog(project,
+                                           "Press \"Mark as Resolved\" when you finish resolving conflicts in the external tool",
+                                           "Merge In External Tool", "Mark as Resolved", "Revert", null) == Messages.YES;
+      }
+
+      if (success) outputFile.finish();
+    }
+    finally {
+      request.applyResult(success ? MergeResult.RESOLVED : MergeResult.CANCEL);
+    }
+  }
+
+  //
+  // Helpers
+  //
+
+  private interface OutputFile {
+    @NotNull
+    String getPath();
+
+    void finish() throws IOException;
+  }
+
+  private static class LocalOutputFile implements OutputFile {
+    @NotNull private final VirtualFile myFile;
+
+    public LocalOutputFile(@NotNull VirtualFile file) {
+      myFile = file;
+    }
+
+    @NotNull
+    @Override
+    public String getPath() {
+      return myFile.getPath();
+    }
+
+    @Override
+    public void finish() {
+      myFile.refresh(false, false);
+    }
+  }
+
+  private static class NonLocalOutputFile implements OutputFile {
+    @NotNull private final VirtualFile myFile;
+    @NotNull private final File myLocalFile;
+
+    public NonLocalOutputFile(@NotNull VirtualFile file, @NotNull File localFile) {
+      myFile = file;
+      myLocalFile = localFile;
+    }
+
+    @NotNull
+    @Override
+    public String getPath() {
+      return myLocalFile.getPath();
+    }
+
+    @Override
+    public void finish() throws IOException {
+      myFile.setBinaryContent(FileUtil.loadFileBytes(myLocalFile));
+    }
+  }
+
+  private static class DocumentOutputFile implements OutputFile {
+    @NotNull private final Document myDocument;
+    @NotNull private final File myLocalFile;
+    @NotNull private final Charset myCharset;
+
+    public DocumentOutputFile(@NotNull Document document, @Nullable Charset charset, @NotNull File localFile) {
+      myDocument = document;
+      myLocalFile = localFile;
+      // TODO: potentially dangerous operation - we're using default charset
+      myCharset = charset != null ? charset : Charset.defaultCharset();
+    }
+
+    @NotNull
+    @Override
+    public String getPath() {
+      return myLocalFile.getPath();
+    }
+
+    @Override
+    public void finish() throws IOException {
+      final String content = StringUtil.convertLineSeparators(FileUtil.loadFile(myLocalFile, myCharset));
+      ApplicationManager.getApplication().runWriteAction(new Runnable() {
+        @Override
+        public void run() {
+          myDocument.setText(content);
+        }
+      });
+    }
+  }
 }

platform/diff-impl/src/com/intellij/diff/tools/external/ExternalMergeTool.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.tools.external;
+
+import com.intellij.diff.DiffManagerEx;
+import com.intellij.diff.contents.DiffContent;
+import com.intellij.diff.contents.DocumentContent;
+import com.intellij.diff.contents.FileContent;
+import com.intellij.diff.merge.MergeRequest;
+import com.intellij.diff.merge.ThreesideMergeRequest;
+import com.intellij.execution.ExecutionException;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.progress.ProcessCanceledException;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.ui.Messages;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.IOException;
+import java.util.List;
+
+public class ExternalMergeTool {
+  public static final Logger LOG = Logger.getInstance(ExternalMergeTool.class);
+
+  public static boolean isDefault() {
+    return ExternalDiffSettings.getInstance().isMergeEnabled();
+  }
+
+  public static boolean isEnabled() {
+    return ExternalDiffSettings.getInstance().isMergeEnabled();
+  }
+
+  public static void show(@Nullable final Project project,
+                          @NotNull final MergeRequest request) {
+    try {
+      if (canShow(request)) {
+        showRequest(project, request);
+      }
+      else {
+        DiffManagerEx.getInstance().showMergeBuiltin(project, request);
+      }
+    }
+    catch (ProcessCanceledException ignore) {
+    }
+    catch (Throwable e) {
+      LOG.error(e);
+      Messages.showErrorDialog(project, e.getMessage(), "Can't Show Merge In External Tool");
+    }
+  }
+
+  public static void showRequest(@Nullable Project project, @NotNull MergeRequest request)
+    throws ExecutionException, IOException {
+    ExternalDiffSettings settings = ExternalDiffSettings.getInstance();
+
+    ExternalDiffToolUtil.executeMerge(project, settings, (ThreesideMergeRequest)request);
+  }
+
+  public static boolean canShow(@NotNull MergeRequest request) {
+    if (request instanceof ThreesideMergeRequest) {
+      DiffContent outputContent = ((ThreesideMergeRequest)request).getOutputContent();
+      if (!canProcessOutputContent(outputContent)) return false;
+
+      List<? extends DiffContent> contents = ((ThreesideMergeRequest)request).getContents();
+      if (contents.size() != 3) return false;
+      for (DiffContent content : contents) {
+        if (!ExternalDiffToolUtil.canCreateFile(content)) return false;
+      }
+      return true;
+    }
+    return false;
+  }
+
+  private static boolean canProcessOutputContent(@NotNull DiffContent content) {
+    if (content instanceof DocumentContent) return true;
+    if (content instanceof FileContent && ((FileContent)content).getFile().isInLocalFileSystem()) return true;
+    return false;
+  }
+}

platform/diff-impl/src/com/intellij/diff/tools/fragmented/UnifiedDiffChange.java

@@ -257,13 +257,17 @@ public class UnifiedDiffChange {
         return new DumbAwareAction() {
           @Override
           public void actionPerformed(AnActionEvent e) {
+            if (myViewer.isStateIsOutOfDate()) return;
+            if (!myViewer.isEditable(sourceSide.other(), true)) return;
+
             final Project project = e.getProject();
             final Document document = myViewer.getDocument(sourceSide.other());
 
             DiffUtil.executeWriteCommand(document, project, "Replace change", new Runnable() {
               @Override
               public void run() {
-                myViewer.applyChange(UnifiedDiffChange.this, sourceSide);
+                myViewer.replaceChange(UnifiedDiffChange.this, sourceSide);
+                myViewer.scheduleRediff();
               }
             });
             // applyChange() will schedule rediff, but we want to try to do it in sync

platform/diff-impl/src/com/intellij/diff/tools/fragmented/UnifiedDiffViewer.java

@@ -30,10 +30,9 @@ import com.intellij.diff.tools.util.base.*;
 import com.intellij.diff.tools.util.side.TwosideTextDiffViewer;
 import com.intellij.diff.util.*;
 import com.intellij.diff.util.DiffUserDataKeysEx.ScrollToPolicy;
+import com.intellij.icons.AllIcons;
 import com.intellij.openapi.Disposable;
-import com.intellij.openapi.actionSystem.AnAction;
-import com.intellij.openapi.actionSystem.CommonDataKeys;
-import com.intellij.openapi.actionSystem.Separator;
+import com.intellij.openapi.actionSystem.*;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.command.undo.UndoManager;
 import com.intellij.openapi.diagnostic.Logger;
@@ -50,6 +49,7 @@ import com.intellij.openapi.fileEditor.OpenFileDescriptor;
 import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.progress.ProcessCanceledException;
 import com.intellij.openapi.progress.ProgressIndicator;
+import com.intellij.openapi.project.DumbAware;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Computable;
 import com.intellij.openapi.util.Pair;
@@ -60,10 +60,7 @@ import gnu.trove.TIntFunction;
 import org.jetbrains.annotations.*;
 
 import javax.swing.*;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Iterator;
-import java.util.List;
+import java.util.*;
 
 import static com.intellij.diff.util.DiffUtil.getLineCount;
 
@@ -124,6 +121,11 @@ public class UnifiedDiffViewer extends ListenerDiffViewerBase {
     new MyOpenInEditorWithMouseAction().register(getEditors());
 
     TextDiffViewerUtil.checkDifferentDocuments(myRequest);
+
+    DiffUtil.registerAction(new ReplaceSelectedChangesAction(Side.LEFT, true), myPanel);
+    DiffUtil.registerAction(new AppendSelectedChangesAction(Side.LEFT, true), myPanel);
+    DiffUtil.registerAction(new ReplaceSelectedChangesAction(Side.RIGHT, true), myPanel);
+    DiffUtil.registerAction(new AppendSelectedChangesAction(Side.RIGHT, true), myPanel);
   }
 
   @Override
@@ -133,6 +135,7 @@ public class UnifiedDiffViewer extends ListenerDiffViewerBase {
     installEditorListeners();
     installTypingSupport();
     myPanel.setLoadingContent(); // We need loading panel only for initial rediff()
+    myPanel.setPersistentNotifications(DiffUtil.getCustomNotifications(myContext, myRequest));
   }
 
   @Override
@@ -208,7 +211,19 @@ public class UnifiedDiffViewer extends ListenerDiffViewerBase {
 
   @NotNull
   protected List<AnAction> createEditorPopupActions() {
-    return TextDiffViewerUtil.createEditorPopupActions();
+    List<AnAction> group = new ArrayList<AnAction>();
+
+    group.add(new ReplaceSelectedChangesAction(Side.LEFT, false));
+    group.add(new AppendSelectedChangesAction(Side.LEFT, false));
+    group.add(new ReplaceSelectedChangesAction(Side.RIGHT, false));
+    group.add(new AppendSelectedChangesAction(Side.RIGHT, false));
+    group.add(new RevertSelectedChangesAction(Side.LEFT));
+    group.add(new RevertSelectedChangesAction(Side.RIGHT));
+    group.add(Separator.getInstance());
+
+    group.addAll(TextDiffViewerUtil.createEditorPopupActions());
+
+    return group;
   }
 
   @CalledInAwt
@@ -621,26 +636,163 @@ public class UnifiedDiffViewer extends ListenerDiffViewerBase {
     scheduleRediff();
   }
 
-  @CalledWithWriteLock
-  public void applyChange(@NotNull UnifiedDiffChange change, @NotNull Side sourceSide) {
-    if (myStateIsOutOfDate || myChangedBlockData == null) return;
+  //
+  // Modification operations
+  //
 
-    Side affectedSide = sourceSide.other();
-    if (!isEditable(affectedSide, true)) return;
+  private abstract class ApplySelectedChangesActionBase extends AnAction implements DumbAware {
+    @NotNull protected final Side myModifiedSide;
+    private final boolean myShortcut;
+
+    public ApplySelectedChangesActionBase(@NotNull Side modifiedSide, boolean shortcut) {
+      myModifiedSide = modifiedSide;
+      myShortcut = shortcut;
+    }
+
+    @Override
+    public void update(@NotNull AnActionEvent e) {
+      if (myShortcut) {
+        // consume shortcut even if there are nothing to do - avoid calling some other action
+        e.getPresentation().setEnabledAndVisible(true);
+        return;
+      }
+
+      Editor editor = e.getData(CommonDataKeys.EDITOR);
+      if (editor != getEditor()) {
+        e.getPresentation().setEnabledAndVisible(false);
+        return;
+      }
+
+      if (!isEditable(myModifiedSide, true) || isStateIsOutOfDate()) {
+        e.getPresentation().setEnabledAndVisible(false);
+        return;
+      }
+
+      e.getPresentation().setVisible(true);
+      e.getPresentation().setEnabled(isSomeChangeSelected());
+    }
+
+    @Override
+    public void actionPerformed(@NotNull final AnActionEvent e) {
+      final List<UnifiedDiffChange> selectedChanges = getSelectedChanges();
+      if (selectedChanges.isEmpty()) return;
+
+      if (!isEditable(myModifiedSide, true)) return;
+      if (isStateIsOutOfDate()) return;
+
+      String title = e.getPresentation().getText() + " selected changes";
+      DiffUtil.executeWriteCommand(getDocument(myModifiedSide), e.getProject(), title, new Runnable() {
+        @Override
+        public void run() {
+          // state is invalidated during apply(), but changes are in reverse order, so they should not conflict with each other
+          apply(selectedChanges);
+          scheduleRediff();
+        }
+      });
+    }
+
+    protected boolean isSomeChangeSelected() {
+      if (myChangedBlockData == null) return false;
+      List<UnifiedDiffChange> changes = myChangedBlockData.getDiffChanges();
+      if (changes.isEmpty()) return false;
+
+      List<Caret> carets = getEditor().getCaretModel().getAllCarets();
+      if (carets.size() != 1) return true;
+      Caret caret = carets.get(0);
+      if (caret.hasSelection()) return true;
+      int line = getEditor().getDocument().getLineNumber(getEditor().getExpectedCaretOffset());
+
+      for (UnifiedDiffChange change : changes) {
+        if (DiffUtil.isSelectedByLine(line, change.getLine1(), change.getLine2())) return true;
+      }
+      return false;
+    }
+
+    @CalledWithWriteLock
+    protected abstract void apply(@NotNull List<UnifiedDiffChange> changes);
+  }
+
+  private class ReplaceSelectedChangesAction extends ApplySelectedChangesActionBase {
+    public ReplaceSelectedChangesAction(@NotNull Side focusedSide, boolean shortcut) {
+      super(focusedSide.other(), shortcut);
+
+      setShortcutSet(ActionManager.getInstance().getAction(focusedSide.select("Diff.ApplyLeftSide", "Diff.ApplyRightSide")).getShortcutSet());
+      getTemplatePresentation().setText("Replace");
+      getTemplatePresentation().setIcon(focusedSide.select(AllIcons.Diff.ArrowRight, AllIcons.Diff.Arrow));
+    }
+
+    @Override
+    protected void apply(@NotNull List<UnifiedDiffChange> changes) {
+      for (UnifiedDiffChange change : changes) {
+        replaceChange(change, myModifiedSide.other());
+      }
+    }
+  }
+
+  private class AppendSelectedChangesAction extends ApplySelectedChangesActionBase {
+    public AppendSelectedChangesAction(@NotNull Side focusedSide, boolean shortcut) {
+      super(focusedSide.other(), shortcut);
+
+      setShortcutSet(ActionManager.getInstance().getAction(focusedSide.select("Diff.AppendLeftSide", "Diff.AppendRightSide")).getShortcutSet());
+      getTemplatePresentation().setText("Insert");
+      getTemplatePresentation().setIcon(focusedSide.select(AllIcons.Diff.ArrowRightDown, AllIcons.Diff.ArrowLeftDown));
+    }
+
+    @Override
+    protected void apply(@NotNull List<UnifiedDiffChange> changes) {
+      for (UnifiedDiffChange change : changes) {
+        appendChange(change, myModifiedSide.other());
+      }
+    }
+  }
+
+  private class RevertSelectedChangesAction extends ApplySelectedChangesActionBase {
+    public RevertSelectedChangesAction(@NotNull Side focusedSide) {
+      super(focusedSide, false);
+      getTemplatePresentation().setText("Revert");
+      getTemplatePresentation().setIcon(AllIcons.Diff.Remove);
+    }
+
+    @Override
+    protected void apply(@NotNull List<UnifiedDiffChange> changes) {
+      for (UnifiedDiffChange change : changes) {
+        replaceChange(change, myModifiedSide.other());
+      }
+    }
+  }
+
+  @CalledWithWriteLock
+  public void replaceChange(@NotNull UnifiedDiffChange change, @NotNull Side sourceSide) {
+    Side outputSide = sourceSide.other();
 
     Document document1 = getDocument(Side.LEFT);
     Document document2 = getDocument(Side.RIGHT);
 
     LineFragment lineFragment = change.getLineFragment();
 
-    DiffUtil.applyModification(affectedSide.select(document1, document2),
-                               affectedSide.getStartLine(lineFragment), affectedSide.getEndLine(lineFragment),
+    DiffUtil.applyModification(outputSide.select(document1, document2),
+                               outputSide.getStartLine(lineFragment), outputSide.getEndLine(lineFragment),
                                sourceSide.select(document1, document2),
                                sourceSide.getStartLine(lineFragment), sourceSide.getEndLine(lineFragment));
 
     // no need to mark myStateIsOutOfDate - it will be made by DocumentListener
     // TODO: we can apply change manually, without marking state out-of-date. But we'll have to schedule rediff anyway.
-    scheduleRediff();
+  }
+
+  @CalledWithWriteLock
+  public void appendChange(@NotNull UnifiedDiffChange change, @NotNull final Side sourceSide) {
+    Side outputSide = sourceSide.other();
+
+    Document document1 = getDocument(Side.LEFT);
+    Document document2 = getDocument(Side.RIGHT);
+
+    LineFragment lineFragment = change.getLineFragment();
+    if (sourceSide.getStartLine(lineFragment) == sourceSide.getEndLine(lineFragment)) return;
+
+    DiffUtil.applyModification(outputSide.select(document1, document2),
+                               outputSide.getEndLine(lineFragment), outputSide.getEndLine(lineFragment),
+                               sourceSide.select(document1, document2),
+                               sourceSide.getStartLine(lineFragment), sourceSide.getEndLine(lineFragment));
   }
 
   //
@@ -775,6 +927,26 @@ public class UnifiedDiffViewer extends ListenerDiffViewerBase {
     return null;
   }
 
+  @NotNull
+  @CalledInAwt
+  private List<UnifiedDiffChange> getSelectedChanges() {
+    if (myChangedBlockData == null) return Collections.emptyList();
+    final BitSet lines = DiffUtil.getSelectedLines(myEditor);
+    List<UnifiedDiffChange> changes = myChangedBlockData.getDiffChanges();
+
+    List<UnifiedDiffChange> affectedChanges = new ArrayList<UnifiedDiffChange>();
+    for (int i = changes.size() - 1; i >= 0; i--) {
+      UnifiedDiffChange change = changes.get(i);
+      int line1 = change.getLine1();
+      int line2 = change.getLine2();
+
+      if (DiffUtil.isSelectedByLine(lines, line1, line2)) {
+        affectedChanges.add(change);
+      }
+    }
+    return affectedChanges;
+  }
+
   @CalledInAwt
   @Nullable
   protected OpenFileDescriptor getOpenFileDescriptor(int offset) {

platform/diff-impl/src/com/intellij/diff/tools/simple/SimpleDiffViewer.java

@@ -30,10 +30,7 @@ import com.intellij.diff.util.*;
 import com.intellij.diff.util.DiffUserDataKeysEx.ScrollToPolicy;
 import com.intellij.icons.AllIcons;
 import com.intellij.openapi.Disposable;
-import com.intellij.openapi.actionSystem.AnAction;
-import com.intellij.openapi.actionSystem.AnActionEvent;
-import com.intellij.openapi.actionSystem.CommonDataKeys;
-import com.intellij.openapi.actionSystem.Separator;
+import com.intellij.openapi.actionSystem.*;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.diff.DiffNavigationContext;
@@ -84,6 +81,11 @@ public class SimpleDiffViewer extends TwosideTextDiffViewer {
     myFoldingModel = new MyFoldingModel(getEditors(), this);
 
     myModifierProvider = new ModifierProvider();
+
+    DiffUtil.registerAction(new ReplaceSelectedChangesAction(Side.LEFT, true), myPanel);
+    DiffUtil.registerAction(new AppendSelectedChangesAction(Side.LEFT, true), myPanel);
+    DiffUtil.registerAction(new ReplaceSelectedChangesAction(Side.RIGHT, true), myPanel);
+    DiffUtil.registerAction(new AppendSelectedChangesAction(Side.RIGHT, true), myPanel);
   }
 
   @Override
@@ -137,9 +139,12 @@ public class SimpleDiffViewer extends TwosideTextDiffViewer {
   protected List<AnAction> createEditorPopupActions() {
     List<AnAction> group = new ArrayList<AnAction>();
 
-    group.add(new ReplaceSelectedChangesAction());
-    group.add(new AppendSelectedChangesAction());
-    group.add(new RevertSelectedChangesAction());
+    group.add(new ReplaceSelectedChangesAction(Side.LEFT, false));
+    group.add(new AppendSelectedChangesAction(Side.LEFT, false));
+    group.add(new ReplaceSelectedChangesAction(Side.RIGHT, false));
+    group.add(new AppendSelectedChangesAction(Side.RIGHT, false));
+    group.add(new RevertSelectedChangesAction(Side.LEFT));
+    group.add(new RevertSelectedChangesAction(Side.RIGHT));
     group.add(Separator.getInstance());
 
     group.addAll(super.createEditorPopupActions());
@@ -491,18 +496,22 @@ public class SimpleDiffViewer extends TwosideTextDiffViewer {
   //
 
   private abstract class ApplySelectedChangesActionBase extends AnAction implements DumbAware {
-    private final boolean myModifyOpposite;
+    @NotNull protected final Side myModifiedSide;
+    private final boolean myShortcut;
 
-    public ApplySelectedChangesActionBase(@Nullable String text,
-                                          @Nullable String description,
-                                          @Nullable Icon icon,
-                                          boolean modifyOpposite) {
-      super(text, description, icon);
-      myModifyOpposite = modifyOpposite;
+    public ApplySelectedChangesActionBase(@NotNull Side modifiedSide, boolean shortcut) {
+      myModifiedSide = modifiedSide;
+      myShortcut = shortcut;
     }
 
     @Override
     public void update(@NotNull AnActionEvent e) {
+      if (myShortcut) {
+        // consume shortcut even if there are nothing to do - avoid calling some other action
+        e.getPresentation().setEnabledAndVisible(true);
+        return;
+      }
+
       Editor editor = e.getData(CommonDataKeys.EDITOR);
       if (editor != getEditor1() && editor != getEditor2()) {
         e.getPresentation().setEnabledAndVisible(false);
@@ -510,30 +519,38 @@ public class SimpleDiffViewer extends TwosideTextDiffViewer {
       }
 
       Side side = Side.fromLeft(editor == getEditor(Side.LEFT));
-      Editor modifiedEditor = getEditor(side.other(myModifyOpposite));
+      if (!isVisible(side)) {
+        e.getPresentation().setEnabledAndVisible(false);
+        return;
+      }
 
+      Editor modifiedEditor = getEditor(myModifiedSide);
       if (!DiffUtil.isEditable(modifiedEditor)) {
         e.getPresentation().setEnabledAndVisible(false);
         return;
       }
 
-      e.getPresentation().setIcon(getIcon(side));
       e.getPresentation().setVisible(true);
       e.getPresentation().setEnabled(isSomeChangeSelected(side));
     }
 
     @Override
     public void actionPerformed(@NotNull final AnActionEvent e) {
-      Editor editor = e.getRequiredData(CommonDataKeys.EDITOR);
+      Editor editor = e.getData(CommonDataKeys.EDITOR);
+      if (editor != getEditor1() && editor != getEditor2()) return;
+
       final Side side = Side.fromLeft(editor == getEditor(Side.LEFT));
       final List<SimpleDiffChange> selectedChanges = getSelectedChanges(side);
+      if (selectedChanges.isEmpty()) return;
+
+      Editor modifiedEditor = getEditor(myModifiedSide);
+      if (!DiffUtil.isEditable(modifiedEditor)) return;
 
-      Editor modifiedEditor = getEditor(side.other(myModifyOpposite));
       String title = e.getPresentation().getText() + " selected changes";
       DiffUtil.executeWriteCommand(modifiedEditor.getDocument(), e.getProject(), title, new Runnable() {
         @Override
         public void run() {
-          apply(side, selectedChanges);
+          apply(selectedChanges);
         }
       });
     }
@@ -554,66 +571,72 @@ public class SimpleDiffViewer extends TwosideTextDiffViewer {
       return false;
     }
 
-    @NotNull
-    protected abstract Icon getIcon(@NotNull Side side);
+    protected abstract boolean isVisible(@NotNull Side side);
 
     @CalledWithWriteLock
-    protected abstract void apply(@NotNull Side side, @NotNull List<SimpleDiffChange> changes);
+    protected abstract void apply(@NotNull List<SimpleDiffChange> changes);
   }
 
   private class ReplaceSelectedChangesAction extends ApplySelectedChangesActionBase {
-    public ReplaceSelectedChangesAction() {
-      super("Replace", null, AllIcons.Diff.Arrow, true);
-    }
+    public ReplaceSelectedChangesAction(@NotNull Side focusedSide, boolean shortcut) {
+      super(focusedSide.other(), shortcut);
 
-    @NotNull
-    @Override
-    protected Icon getIcon(@NotNull Side side) {
-      return side.isLeft() ? AllIcons.Diff.ArrowRight : AllIcons.Diff.Arrow;
+      setShortcutSet(ActionManager.getInstance().getAction(focusedSide.select("Diff.ApplyLeftSide", "Diff.ApplyRightSide")).getShortcutSet());
+      getTemplatePresentation().setText("Replace");
+      getTemplatePresentation().setIcon(focusedSide.select(AllIcons.Diff.ArrowRight, AllIcons.Diff.Arrow));
     }
 
     @Override
-    protected void apply(@NotNull Side side, @NotNull List<SimpleDiffChange> changes) {
+    protected boolean isVisible(@NotNull Side side) {
+      return side == myModifiedSide.other();
+    }
+
+    @Override
+    protected void apply(@NotNull List<SimpleDiffChange> changes) {
       for (SimpleDiffChange change : changes) {
-        replaceChange(change, side);
+        replaceChange(change, myModifiedSide.other());
       }
     }
   }
 
   private class AppendSelectedChangesAction extends ApplySelectedChangesActionBase {
-    public AppendSelectedChangesAction() {
-      super("Insert", null, AllIcons.Diff.ArrowLeftDown, true);
-    }
+    public AppendSelectedChangesAction(@NotNull Side focusedSide, boolean shortcut) {
+      super(focusedSide.other(), shortcut);
 
-    @NotNull
-    @Override
-    protected Icon getIcon(@NotNull Side side) {
-      return side.isLeft() ? AllIcons.Diff.ArrowRightDown : AllIcons.Diff.ArrowLeftDown;
+      setShortcutSet(ActionManager.getInstance().getAction(focusedSide.select("Diff.AppendLeftSide", "Diff.AppendRightSide")).getShortcutSet());
+      getTemplatePresentation().setText("Insert");
+      getTemplatePresentation().setIcon(focusedSide.select(AllIcons.Diff.ArrowRightDown, AllIcons.Diff.ArrowLeftDown));
     }
 
     @Override
-    protected void apply(@NotNull Side side, @NotNull List<SimpleDiffChange> changes) {
+    protected boolean isVisible(@NotNull Side side) {
+      return side == myModifiedSide.other();
+    }
+
+    @Override
+    protected void apply(@NotNull List<SimpleDiffChange> changes) {
       for (SimpleDiffChange change : changes) {
-        appendChange(change, side);
+        appendChange(change, myModifiedSide.other());
       }
     }
   }
 
   private class RevertSelectedChangesAction extends ApplySelectedChangesActionBase {
-    public RevertSelectedChangesAction() {
-      super("Revert", null, AllIcons.Diff.Remove, false);
-    }
-
-    @NotNull
-    @Override
-    protected Icon getIcon(@NotNull Side side) {
-      return AllIcons.Diff.Remove;
+    public RevertSelectedChangesAction(@NotNull Side focusedSide) {
+      super(focusedSide, false);
+      getTemplatePresentation().setText("Revert");
+      getTemplatePresentation().setIcon(AllIcons.Diff.Remove);
     }
 
     @Override
-    protected void apply(@NotNull Side side, @NotNull List<SimpleDiffChange> changes) {
+    protected boolean isVisible(@NotNull Side side) {
+      return side == myModifiedSide;
+    }
+
+    @Override
+    protected void apply(@NotNull List<SimpleDiffChange> changes) {
       for (SimpleDiffChange change : changes) {
-        replaceChange(change, side.other());
+        replaceChange(change, myModifiedSide.other());
       }
     }
   }

platform/diff-impl/src/com/intellij/diff/tools/simple/SimpleThreesideDiffChange.java

@@ -15,28 +15,25 @@
  */
 package com.intellij.diff.tools.simple;
 
-import com.intellij.diff.comparison.ComparisonManager;
 import com.intellij.diff.comparison.ComparisonPolicy;
 import com.intellij.diff.fragments.MergeLineFragment;
-import com.intellij.diff.util.*;
+import com.intellij.diff.util.DiffDrawUtil;
+import com.intellij.diff.util.DiffUtil;
+import com.intellij.diff.util.TextDiffType;
+import com.intellij.diff.util.ThreeSide;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.editor.Editor;
-import com.intellij.openapi.editor.ex.DocumentEx;
 import com.intellij.openapi.editor.ex.EditorEx;
 import com.intellij.openapi.editor.markup.RangeHighlighter;
 import com.intellij.openapi.editor.markup.SeparatorPlacement;
-import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
 import java.util.List;
 
-public class SimpleThreesideDiffChange {
-  @NotNull private final MergeLineFragment myFragment;
+public class SimpleThreesideDiffChange extends ThreesideDiffChangeBase {
   @NotNull private final List<? extends EditorEx> myEditors;
-
-  @NotNull private ConflictType myType;
+  @NotNull private final MergeLineFragment myFragment;
 
   @NotNull private final List<RangeHighlighter> myHighlighters = new ArrayList<RangeHighlighter>();
 
@@ -46,10 +43,9 @@ public class SimpleThreesideDiffChange {
   public SimpleThreesideDiffChange(@NotNull MergeLineFragment fragment,
                                    @NotNull List<? extends EditorEx> editors,
                                    @NotNull ComparisonPolicy policy) {
-    myFragment = fragment;
+    super(fragment, editors, policy);
     myEditors = editors;
-
-    myType = calcType(fragment, editors, policy);
+    myFragment = fragment;
 
     installHighlighter();
   }
@@ -58,8 +54,8 @@ public class SimpleThreesideDiffChange {
     assert myHighlighters.isEmpty();
 
     createHighlighter(ThreeSide.BASE);
-    if (myType.isLeftChange()) createHighlighter(ThreeSide.LEFT);
-    if (myType.isRightChange()) createHighlighter(ThreeSide.RIGHT);
+    if (getType().isLeftChange()) createHighlighter(ThreeSide.LEFT);
+    if (getType().isRightChange()) createHighlighter(ThreeSide.RIGHT);
   }
 
   public void destroyHighlighter() {
@@ -107,24 +103,16 @@ public class SimpleThreesideDiffChange {
   // Getters
   //
 
+  @Override
   public int getStartLine(@NotNull ThreeSide side) {
     return myFragment.getStartLine(side) + side.select(myLineStartShifts);
   }
 
+  @Override
   public int getEndLine(@NotNull ThreeSide side) {
     return myFragment.getEndLine(side) + side.select(myLineEndShifts);
   }
 
-  @NotNull
-  public TextDiffType getDiffType() {
-    return myType.getDiffType();
-  }
-
-  @NotNull
-  public ConflictType getType() {
-    return myType;
-  }
-
   //
   // Shift
   //
@@ -140,125 +128,4 @@ public class SimpleThreesideDiffChange {
 
     return newRange.damaged;
   }
-
-  //
-  // Type
-  //
-
-  @NotNull
-  private static ConflictType calcType(@NotNull MergeLineFragment fragment,
-                                       @NotNull List<? extends EditorEx> editors,
-                                       @NotNull ComparisonPolicy policy) {
-    boolean isLeftEmpty = isIntervalEmpty(fragment, ThreeSide.LEFT);
-    boolean isBaseEmpty = isIntervalEmpty(fragment, ThreeSide.BASE);
-    boolean isRightEmpty = isIntervalEmpty(fragment, ThreeSide.RIGHT);
-    assert !isLeftEmpty || !isBaseEmpty || !isRightEmpty;
-
-    if (isBaseEmpty) {
-      if (isLeftEmpty) { // --=
-        return new ConflictType(TextDiffType.INSERTED, false, true);
-      }
-      else if (isRightEmpty) { // =--
-        return new ConflictType(TextDiffType.INSERTED, true, false);
-      }
-      else { // =-=
-        boolean equalModifications = compareLeftAndRight(fragment, editors, policy);
-        return new ConflictType(equalModifications ? TextDiffType.INSERTED : TextDiffType.CONFLICT);
-      }
-    }
-    else {
-      if (isLeftEmpty && isRightEmpty) { // -=-
-        return new ConflictType(TextDiffType.DELETED);
-      }
-      else { // -==, ==-, ===
-        boolean unchangedLeft = compareWithBase(fragment, editors, ThreeSide.LEFT);
-        boolean unchangedRight = compareWithBase(fragment, editors, ThreeSide.RIGHT);
-        assert !unchangedLeft || !unchangedRight;
-
-        if (unchangedLeft) return new ConflictType(isRightEmpty ? TextDiffType.DELETED : TextDiffType.MODIFIED, false, true);
-        if (unchangedRight) return new ConflictType(isLeftEmpty ? TextDiffType.DELETED : TextDiffType.MODIFIED, true, false);
-
-        boolean equalModifications = compareLeftAndRight(fragment, editors, policy);
-        return new ConflictType(equalModifications ? TextDiffType.MODIFIED : TextDiffType.CONFLICT);
-      }
-    }
-  }
-
-  private static boolean compareLeftAndRight(@NotNull MergeLineFragment fragment,
-                                             @NotNull List<? extends EditorEx> editors,
-                                             @NotNull ComparisonPolicy policy) {
-    CharSequence content1 = getRangeContent(fragment, editors, ThreeSide.LEFT);
-    CharSequence content2 = getRangeContent(fragment, editors, ThreeSide.RIGHT);
-
-    if (policy == ComparisonPolicy.IGNORE_WHITESPACES) {
-      if (content1 == null) content1 = "";
-      if (content2 == null) content2 = "";
-    }
-
-    if (content1 == null && content2 == null) return true;
-    if (content1 == null ^ content2 == null) return false;
-
-    return ComparisonManager.getInstance().isEquals(content1, content2, policy);
-  }
-
-  private static boolean compareWithBase(@NotNull MergeLineFragment fragment,
-                                         @NotNull List<? extends EditorEx> editors,
-                                         @NotNull ThreeSide side) {
-    CharSequence content1 = getRangeContent(fragment, editors, ThreeSide.BASE);
-    CharSequence content2 = getRangeContent(fragment, editors, side);
-
-    return StringUtil.equals(content1, content2);
-  }
-
-  @Nullable
-  private static CharSequence getRangeContent(@NotNull MergeLineFragment fragment,
-                                              @NotNull List<? extends EditorEx> editors,
-                                              @NotNull ThreeSide side) {
-    DocumentEx document = side.select(editors).getDocument();
-    int line1 = fragment.getStartLine(side);
-    int line2 = fragment.getEndLine(side);
-    if (line1 == line2) return null;
-    return DiffUtil.getLinesContent(document, line1, line2);
-  }
-
-  private static boolean isIntervalEmpty(@NotNull MergeLineFragment fragment, @NotNull ThreeSide side) {
-    return fragment.getStartLine(side) == fragment.getEndLine(side);
-  }
-
-  //
-  // Helpers
-  //
-
-  public static class ConflictType {
-    @NotNull private final TextDiffType myType;
-    private final boolean myLeftChange;
-    private final boolean myRightChange;
-
-    public ConflictType(@NotNull TextDiffType type) {
-      this(type, true, true);
-    }
-
-    public ConflictType(@NotNull TextDiffType type, boolean leftChange, boolean rightChange) {
-      myType = type;
-      myLeftChange = leftChange;
-      myRightChange = rightChange;
-    }
-
-    @NotNull
-    public TextDiffType getDiffType() {
-      return myType;
-    }
-
-    public boolean isLeftChange() {
-      return myLeftChange;
-    }
-
-    public boolean isRightChange() {
-      return myRightChange;
-    }
-
-    public boolean isChange(@NotNull Side side) {
-      return side.isLeft() ? myLeftChange : myRightChange;
-    }
-  }
 }

platform/diff-impl/src/com/intellij/diff/tools/simple/SimpleThreesideDiffViewer.java

@@ -26,7 +26,7 @@ import com.intellij.diff.contents.DocumentContent;
 import com.intellij.diff.fragments.MergeLineFragment;
 import com.intellij.diff.requests.ContentDiffRequest;
 import com.intellij.diff.requests.DiffRequest;
-import com.intellij.diff.tools.util.*;
+import com.intellij.diff.tools.util.DiffNotifications;
 import com.intellij.diff.tools.util.base.IgnorePolicy;
 import com.intellij.diff.tools.util.base.TextDiffViewerUtil;
 import com.intellij.diff.tools.util.side.ThreesideTextDiffViewer;
@@ -34,79 +34,31 @@ import com.intellij.diff.util.DiffDividerDrawUtil;
 import com.intellij.diff.util.DiffUtil;
 import com.intellij.diff.util.Side;
 import com.intellij.diff.util.ThreeSide;
-import com.intellij.diff.util.*;
-import com.intellij.diff.util.DiffUserDataKeysEx.ScrollToPolicy;
-import com.intellij.openapi.Disposable;
 import com.intellij.openapi.actionSystem.AnAction;
 import com.intellij.openapi.actionSystem.Separator;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.diagnostic.Logger;
-import com.intellij.openapi.diff.DiffBundle;
 import com.intellij.openapi.editor.Document;
-import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.event.DocumentEvent;
-import com.intellij.openapi.editor.ex.EditorEx;
 import com.intellij.openapi.progress.ProcessCanceledException;
 import com.intellij.openapi.progress.ProgressIndicator;
 import com.intellij.openapi.util.Computable;
-import com.intellij.openapi.util.UserDataHolder;
-import com.intellij.openapi.util.text.StringUtil;
-import com.intellij.util.Function;
 import com.intellij.util.containers.ContainerUtil;
-import com.intellij.util.ui.ButtonlessScrollBarUI;
 import org.jetbrains.annotations.CalledInAwt;
-import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
-import javax.swing.*;
-import java.awt.*;
 import java.util.ArrayList;
-import java.util.Iterator;
 import java.util.List;
 
-// TODO: extract common methods with Twoside
-public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
+public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewerEx {
   public static final Logger LOG = Logger.getInstance(SimpleThreesideDiffViewer.class);
 
-  @NotNull private final SyncScrollSupport.SyncScrollable mySyncScrollable1;
-  @NotNull private final SyncScrollSupport.SyncScrollable mySyncScrollable2;
-
-  @NotNull private final PrevNextDifferenceIterable myPrevNextDifferenceIterable;
-  @NotNull private final MyStatusPanel myStatusPanel;
-
   @NotNull private final List<SimpleThreesideDiffChange> myDiffChanges = new ArrayList<SimpleThreesideDiffChange>();
   @NotNull private final List<SimpleThreesideDiffChange> myInvalidDiffChanges = new ArrayList<SimpleThreesideDiffChange>();
-  private int myChangesCount = -1;
-  private int myConflictsCount = -1;
-
-  @NotNull private final MyFoldingModel myFoldingModel;
-  @NotNull private final MyInitialScrollHelper myInitialScrollHelper = new MyInitialScrollHelper();
 
   public SimpleThreesideDiffViewer(@NotNull DiffContext context, @NotNull DiffRequest request) {
     super(context, (ContentDiffRequest)request);
-
-    mySyncScrollable1 = new MySyncScrollable(Side.LEFT);
-    mySyncScrollable2 = new MySyncScrollable(Side.RIGHT);
-    myPrevNextDifferenceIterable = new MyPrevNextDifferenceIterable();
-    myStatusPanel = new MyStatusPanel();
-    myFoldingModel = new MyFoldingModel(getEditors().toArray(new EditorEx[3]), this);
-  }
-
-  @Override
-  @CalledInAwt
-  protected void onInit() {
-    super.onInit();
-    myContentPanel.setPainter(new MyDividerPainter(Side.LEFT), Side.LEFT);
-    myContentPanel.setPainter(new MyDividerPainter(Side.RIGHT), Side.RIGHT);
-    myContentPanel.setScrollbarPainter(new MyScrollbarPainter());
-  }
-
-  @Override
-  @CalledInAwt
-  protected void onDispose() {
-    destroyChangedBlocks();
-    super.onDispose();
   }
 
   @NotNull
@@ -145,30 +97,10 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
     return group;
   }
 
-  @Override
-  @CalledInAwt
-  protected void processContextHints() {
-    super.processContextHints();
-    myInitialScrollHelper.processContext(myRequest);
-  }
-
-  @Override
-  @CalledInAwt
-  protected void updateContextHints() {
-    super.updateContextHints();
-    myFoldingModel.updateContext(myRequest, getFoldingModelSettings());
-    myInitialScrollHelper.updateContext(myRequest);
-  }
-
   //
   // Diff
   //
 
-  @NotNull
-  public FoldingModelSupport.Settings getFoldingModelSettings() {
-    return TextDiffViewerUtil.getFoldingModelSettings(myContext);
-  }
-
   @Override
   protected void onSlowRediff() {
     super.onSlowRediff();
@@ -227,13 +159,11 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
         myFoldingModel.updateContext(myRequest, getFoldingModelSettings());
         clearDiffPresentation();
 
-        myChangesCount = 0;
-        myConflictsCount = 0;
+        resetChangeCounters();
         for (MergeLineFragment fragment : fragments) {
           SimpleThreesideDiffChange change = new SimpleThreesideDiffChange(fragment, getEditors(), comparisonPolicy);
           myDiffChanges.add(change);
-          if (change.getDiffType() != TextDiffType.CONFLICT) myChangesCount++;
-          if (change.getDiffType() == TextDiffType.CONFLICT) myConflictsCount++;
+          onChangeAdded(change);
         }
 
         myFoldingModel.install(fragments, myRequest, getFoldingModelSettings());
@@ -246,24 +176,8 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
     };
   }
 
-  @NotNull
-  private Runnable applyNotification(@Nullable final JComponent notification) {
-    return new Runnable() {
-      @Override
-      public void run() {
-        clearDiffPresentation();
-        if (notification != null) myPanel.addNotification(notification);
-      }
-    };
-  }
-
-  private void clearDiffPresentation() {
-    myStatusPanel.setBusy(false);
-    myPanel.resetNotifications();
-    destroyChangedBlocks();
-  }
-
-  private void destroyChangedBlocks() {
+  protected void destroyChangedBlocks() {
+    super.destroyChangedBlocks();
     for (SimpleThreesideDiffChange change : myDiffChanges) {
       change.destroyHighlighter();
     }
@@ -273,14 +187,6 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
       change.destroyHighlighter();
     }
     myInvalidDiffChanges.clear();
-
-    myChangesCount = -1;
-    myConflictsCount = -1;
-
-    myFoldingModel.destroy();
-
-    myContentPanel.repaintDividers();
-    myStatusPanel.update();
   }
 
   //
@@ -319,28 +225,6 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
     }
   }
 
-  @Override
-  protected void onDocumentChange(@NotNull DocumentEvent e) {
-    super.onDocumentChange(e);
-    myFoldingModel.onDocumentChanged(e);
-  }
-
-  @CalledInAwt
-  protected boolean doScrollToChange(@NotNull ScrollToPolicy scrollToPolicy) {
-    SimpleThreesideDiffChange targetChange = scrollToPolicy.select(myDiffChanges);
-    if (targetChange == null) return false;
-
-    doScrollToChange(targetChange, false);
-    return true;
-  }
-
-  private void doScrollToChange(@NotNull SimpleThreesideDiffChange change, boolean animated) {
-    // TODO: use anchors to fix scrolling issue at the start/end of file
-    EditorEx editor = getCurrentEditor();
-    int line = change.getStartLine(getCurrentSide());
-    DiffUtil.scrollEditor(editor, line, animated);
-  }
-
   @NotNull
   private IgnorePolicy getIgnorePolicy() {
     IgnorePolicy policy = getTextSettings().getIgnorePolicy();
@@ -353,41 +237,20 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
   //
 
   @NotNull
-  protected List<SimpleThreesideDiffChange> getDiffChanges() {
+  public List<SimpleThreesideDiffChange> getChanges() {
     return myDiffChanges;
   }
 
   @NotNull
   @Override
-  protected SyncScrollSupport.SyncScrollable getSyncScrollable(@NotNull Side side) {
-    return side.select(mySyncScrollable1, mySyncScrollable2);
-  }
-
-  @NotNull
-  @Override
-  protected JComponent getStatusPanel() {
-    return myStatusPanel;
+  protected DiffDividerDrawUtil.DividerPaintable getDividerPaintable(@NotNull Side side) {
+    return new MyDividerPaintable(side);
   }
 
   //
   // Misc
   //
 
-  @Nullable
-  @CalledInAwt
-  private SimpleThreesideDiffChange getSelectedChange(@NotNull ThreeSide side) {
-    EditorEx editor = getEditor(side);
-    int caretLine = editor.getCaretModel().getLogicalPosition().line;
-
-    for (SimpleThreesideDiffChange change : myDiffChanges) {
-      int line1 = change.getStartLine(side);
-      int line2 = change.getEndLine(side);
-
-      if (DiffUtil.isSelectedByLine(caretLine, line1, line2)) return change;
-    }
-    return null;
-  }
-
   @SuppressWarnings("MethodOverridesStaticMethodOfSuperclass")
   public static boolean canShowRequest(@NotNull DiffContext context, @NotNull DiffRequest request) {
     return ThreesideTextDiffViewer.canShowRequest(context, request);
@@ -397,46 +260,6 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
   // Actions
   //
 
-  private class MyPrevNextDifferenceIterable extends PrevNextDifferenceIterableBase<SimpleThreesideDiffChange> {
-    @NotNull
-    @Override
-    protected List<SimpleThreesideDiffChange> getChanges() {
-      return myDiffChanges;
-    }
-
-    @NotNull
-    @Override
-    protected EditorEx getEditor() {
-      return getCurrentEditor();
-    }
-
-    @Override
-    protected int getStartLine(@NotNull SimpleThreesideDiffChange change) {
-      return change.getStartLine(getCurrentSide());
-    }
-
-    @Override
-    protected int getEndLine(@NotNull SimpleThreesideDiffChange change) {
-      return change.getEndLine(getCurrentSide());
-    }
-
-    @Override
-    protected void scrollToChange(@NotNull SimpleThreesideDiffChange change) {
-      doScrollToChange(change, true);
-    }
-  }
-
-  private class MyToggleExpandByDefaultAction extends TextDiffViewerUtil.ToggleExpandByDefaultAction {
-    public MyToggleExpandByDefaultAction() {
-      super(getTextSettings());
-    }
-
-    @Override
-    protected void expandAll(boolean expand) {
-      myFoldingModel.expandAll(expand);
-    }
-  }
-
   private class MyIgnorePolicySettingAction extends TextDiffViewerUtil.IgnorePolicySettingAction {
     public MyIgnorePolicySettingAction() {
       super(getTextSettings());
@@ -472,48 +295,6 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
   // Helpers
   //
 
-  @Nullable
-  @Override
-  public Object getData(@NonNls String dataId) {
-    if (DiffDataKeys.PREV_NEXT_DIFFERENCE_ITERABLE.is(dataId)) {
-      return myPrevNextDifferenceIterable;
-    }
-    else if (DiffDataKeys.CURRENT_CHANGE_RANGE.is(dataId)) {
-      SimpleThreesideDiffChange change = getSelectedChange(getCurrentSide());
-      if (change != null) {
-        return new LineRange(change.getStartLine(getCurrentSide()), change.getEndLine(getCurrentSide()));
-      }
-    }
-
-    return super.getData(dataId);
-  }
-
-  private class MySyncScrollable extends BaseSyncScrollable {
-    @NotNull private final Side mySide;
-
-    public MySyncScrollable(@NotNull Side side) {
-      mySide = side;
-    }
-
-    @Override
-    public boolean isSyncScrollEnabled() {
-      return getTextSettings().isEnableSyncScroll();
-    }
-
-    @Override
-    protected void processHelper(@NotNull ScrollHelper helper) {
-      ThreeSide left = mySide.select(ThreeSide.LEFT, ThreeSide.BASE);
-      ThreeSide right = mySide.select(ThreeSide.BASE, ThreeSide.RIGHT);
-
-      if (!helper.process(0, 0)) return;
-      for (SimpleThreesideDiffChange diffChange : myDiffChanges) {
-        if (!helper.process(diffChange.getStartLine(left), diffChange.getStartLine(right))) return;
-        if (!helper.process(diffChange.getEndLine(left), diffChange.getEndLine(right))) return;
-      }
-      helper.process(getEditor(left).getDocument().getLineCount(), getEditor(right).getDocument().getLineCount());
-    }
-  }
-
   private class MyDividerPaintable implements DiffDividerDrawUtil.DividerPaintable {
     @NotNull private final Side mySide;
 
@@ -527,7 +308,7 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
       ThreeSide right = mySide.select(ThreeSide.BASE, ThreeSide.RIGHT);
 
       for (SimpleThreesideDiffChange diffChange : myDiffChanges) {
-        if (!diffChange.getType().isChange(mySide)) continue;
+        if (!diffChange.isChange(mySide)) continue;
         if (!handler.process(diffChange.getStartLine(left), diffChange.getEndLine(left),
                              diffChange.getStartLine(right), diffChange.getEndLine(right),
                              diffChange.getDiffType().getColor(getEditor(ThreeSide.BASE)))) {
@@ -536,117 +317,4 @@ public class SimpleThreesideDiffViewer extends ThreesideTextDiffViewer {
       }
     }
   }
-
-  private class MyDividerPainter implements DiffSplitter.Painter {
-    @NotNull private final Side mySide;
-    @NotNull private final MyDividerPaintable myPaintable;
-
-    public MyDividerPainter(@NotNull Side side) {
-      mySide = side;
-      myPaintable = new MyDividerPaintable(side);
-    }
-
-    @Override
-    public void paint(@NotNull Graphics g, @NotNull JComponent divider) {
-      Graphics2D gg = DiffDividerDrawUtil.getDividerGraphics(g, divider, getEditor(ThreeSide.BASE).getComponent());
-
-      gg.setColor(DiffDrawUtil.getDividerColor(getEditor(ThreeSide.BASE)));
-      gg.fill(gg.getClipBounds());
-
-      Editor editor1 = mySide.select(getEditor(ThreeSide.LEFT), getEditor(ThreeSide.BASE));
-      Editor editor2 = mySide.select(getEditor(ThreeSide.BASE), getEditor(ThreeSide.RIGHT));
-
-      //DividerPolygonUtil.paintSimplePolygons(gg, divider.getWidth(), editor1, editor2, myPaintable);
-      DiffDividerDrawUtil.paintPolygons(gg, divider.getWidth(), editor1, editor2, myPaintable);
-
-      myFoldingModel.paintOnDivider(gg, divider, mySide);
-
-      gg.dispose();
-    }
-  }
-
-  private class MyScrollbarPainter implements ButtonlessScrollBarUI.ScrollbarRepaintCallback {
-    @NotNull private final MyDividerPaintable myPaintable = new MyDividerPaintable(Side.RIGHT);
-
-    @Override
-    public void call(Graphics g) {
-      EditorEx editor1 = getEditor(ThreeSide.BASE);
-      EditorEx editor2 = getEditor(ThreeSide.RIGHT);
-
-      int width = editor1.getScrollPane().getVerticalScrollBar().getWidth();
-      DiffDividerDrawUtil.paintPolygonsOnScrollbar((Graphics2D)g, width, editor1, editor2, myPaintable);
-
-      myFoldingModel.paintOnScrollbar((Graphics2D)g, width);
-    }
-  }
-
-  private class MyStatusPanel extends StatusPanel {
-    @Nullable
-    @Override
-    protected String getMessage() {
-      if (myChangesCount < 0 || myConflictsCount < 0) return null;
-      if (myChangesCount == 0 && myConflictsCount == 0) {
-        return DiffBundle.message("merge.dialog.all.conflicts.resolved.message.text");
-      }
-      return makeCounterWord(myChangesCount, "change") + ". " + makeCounterWord(myConflictsCount, "conflict");
-    }
-
-    @NotNull
-    private String makeCounterWord(int number, @NotNull String word) {
-      if (number == 0) {
-        return "No " + StringUtil.pluralize(word);
-      }
-      return number + " " + StringUtil.pluralize(word, number);
-    }
-  }
-
-  private static class MyFoldingModel extends FoldingModelSupport {
-    private final MyPaintable myPaintable1 = new MyPaintable(0, 1);
-    private final MyPaintable myPaintable2 = new MyPaintable(1, 2);
-
-    public MyFoldingModel(@NotNull EditorEx[] editors, @NotNull Disposable disposable) {
-      super(editors, disposable);
-      assert editors.length == 3;
-    }
-
-    public void install(@Nullable List<MergeLineFragment> fragments,
-                        @NotNull UserDataHolder context,
-                        @NotNull FoldingModelSupport.Settings settings) {
-      Iterator<int[]> it = map(fragments, new Function<MergeLineFragment, int[]>() {
-        @Override
-        public int[] fun(MergeLineFragment fragment) {
-          return new int[]{
-            fragment.getStartLine(ThreeSide.LEFT),
-            fragment.getEndLine(ThreeSide.LEFT),
-            fragment.getStartLine(ThreeSide.BASE),
-            fragment.getEndLine(ThreeSide.BASE),
-            fragment.getStartLine(ThreeSide.RIGHT),
-            fragment.getEndLine(ThreeSide.RIGHT)};
-        }
-      });
-      install(it, context, settings);
-    }
-
-    public void paintOnDivider(@NotNull Graphics2D gg, @NotNull Component divider, @NotNull Side side) {
-      MyPaintable paintable = side.select(myPaintable1, myPaintable2);
-      paintable.paintOnDivider(gg, divider);
-    }
-
-    public void paintOnScrollbar(@NotNull Graphics2D gg, int width) {
-      myPaintable2.paintOnScrollbar(gg, width);
-    }
-  }
-
-  private class MyInitialScrollHelper extends MyInitialScrollPositionHelper {
-    @Override
-    protected boolean doScrollToChange() {
-      if (myScrollToChange == null) return false;
-      return SimpleThreesideDiffViewer.this.doScrollToChange(myScrollToChange);
-    }
-
-    @Override
-    protected boolean doScrollToFirstChange() {
-      return SimpleThreesideDiffViewer.this.doScrollToChange(ScrollToPolicy.FIRST_CHANGE);
-    }
-  }
 }

platform/diff-impl/src/com/intellij/diff/tools/simple/ThreesideDiffChangeBase.java

@@ -0,0 +1,188 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.tools.simple;
+
+import com.intellij.diff.comparison.ComparisonManager;
+import com.intellij.diff.comparison.ComparisonPolicy;
+import com.intellij.diff.fragments.MergeLineFragment;
+import com.intellij.diff.util.DiffUtil;
+import com.intellij.diff.util.Side;
+import com.intellij.diff.util.TextDiffType;
+import com.intellij.diff.util.ThreeSide;
+import com.intellij.openapi.editor.ex.DocumentEx;
+import com.intellij.openapi.editor.ex.EditorEx;
+import com.intellij.openapi.util.text.StringUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+
+public abstract class ThreesideDiffChangeBase {
+  @NotNull private ConflictType myType;
+
+  public ThreesideDiffChangeBase(@NotNull MergeLineFragment fragment,
+                                 @NotNull List<? extends EditorEx> editors,
+                                 @NotNull ComparisonPolicy policy) {
+    myType = calcType(fragment, editors, policy);
+  }
+
+  //
+  // Getters
+  //
+
+  public abstract int getStartLine(@NotNull ThreeSide side);
+
+  public abstract int getEndLine(@NotNull ThreeSide side);
+
+  @NotNull
+  public TextDiffType getDiffType() {
+    return myType.getDiffType();
+  }
+
+  @NotNull
+  public ConflictType getType() {
+    return myType;
+  }
+
+  public boolean isConflict() {
+    return getDiffType() == TextDiffType.CONFLICT;
+  }
+
+  public boolean isChange(@NotNull Side side) {
+    return myType.isChange(side);
+  }
+
+  //
+  // Type
+  //
+
+  @NotNull
+  private static ConflictType calcType(@NotNull MergeLineFragment fragment,
+                                       @NotNull List<? extends EditorEx> editors,
+                                       @NotNull ComparisonPolicy policy) {
+    boolean isLeftEmpty = isIntervalEmpty(fragment, ThreeSide.LEFT);
+    boolean isBaseEmpty = isIntervalEmpty(fragment, ThreeSide.BASE);
+    boolean isRightEmpty = isIntervalEmpty(fragment, ThreeSide.RIGHT);
+    assert !isLeftEmpty || !isBaseEmpty || !isRightEmpty;
+
+    if (isBaseEmpty) {
+      if (isLeftEmpty) { // --=
+        return new ConflictType(TextDiffType.INSERTED, false, true);
+      }
+      else if (isRightEmpty) { // =--
+        return new ConflictType(TextDiffType.INSERTED, true, false);
+      }
+      else { // =-=
+        boolean equalModifications = compareLeftAndRight(fragment, editors, policy);
+        return new ConflictType(equalModifications ? TextDiffType.INSERTED : TextDiffType.CONFLICT);
+      }
+    }
+    else {
+      if (isLeftEmpty && isRightEmpty) { // -=-
+        return new ConflictType(TextDiffType.DELETED);
+      }
+      else { // -==, ==-, ===
+        boolean unchangedLeft = compareWithBase(fragment, editors, ThreeSide.LEFT);
+        boolean unchangedRight = compareWithBase(fragment, editors, ThreeSide.RIGHT);
+        assert !unchangedLeft || !unchangedRight;
+
+        if (unchangedLeft) return new ConflictType(isRightEmpty ? TextDiffType.DELETED : TextDiffType.MODIFIED, false, true);
+        if (unchangedRight) return new ConflictType(isLeftEmpty ? TextDiffType.DELETED : TextDiffType.MODIFIED, true, false);
+
+        boolean equalModifications = compareLeftAndRight(fragment, editors, policy);
+        return new ConflictType(equalModifications ? TextDiffType.MODIFIED : TextDiffType.CONFLICT);
+      }
+    }
+  }
+
+  private static boolean compareLeftAndRight(@NotNull MergeLineFragment fragment,
+                                             @NotNull List<? extends EditorEx> editors,
+                                             @NotNull ComparisonPolicy policy) {
+    CharSequence content1 = getRangeContent(fragment, editors, ThreeSide.LEFT);
+    CharSequence content2 = getRangeContent(fragment, editors, ThreeSide.RIGHT);
+
+    if (policy == ComparisonPolicy.IGNORE_WHITESPACES) {
+      if (content1 == null) content1 = "";
+      if (content2 == null) content2 = "";
+    }
+
+    if (content1 == null && content2 == null) return true;
+    if (content1 == null ^ content2 == null) return false;
+
+    return ComparisonManager.getInstance().isEquals(content1, content2, policy);
+  }
+
+  private static boolean compareWithBase(@NotNull MergeLineFragment fragment,
+                                         @NotNull List<? extends EditorEx> editors,
+                                         @NotNull ThreeSide side) {
+    CharSequence content1 = getRangeContent(fragment, editors, ThreeSide.BASE);
+    CharSequence content2 = getRangeContent(fragment, editors, side);
+
+    return StringUtil.equals(content1, content2);
+  }
+
+  @Nullable
+  private static CharSequence getRangeContent(@NotNull MergeLineFragment fragment,
+                                              @NotNull List<? extends EditorEx> editors,
+                                              @NotNull ThreeSide side) {
+    DocumentEx document = side.select(editors).getDocument();
+    int line1 = fragment.getStartLine(side);
+    int line2 = fragment.getEndLine(side);
+    if (line1 == line2) return null;
+    return DiffUtil.getLinesContent(document, line1, line2);
+  }
+
+  private static boolean isIntervalEmpty(@NotNull MergeLineFragment fragment, @NotNull ThreeSide side) {
+    return fragment.getStartLine(side) == fragment.getEndLine(side);
+  }
+
+  //
+  // Helpers
+  //
+
+  public static class ConflictType {
+    @NotNull private final TextDiffType myType;
+    private final boolean myLeftChange;
+    private final boolean myRightChange;
+
+    public ConflictType(@NotNull TextDiffType type) {
+      this(type, true, true);
+    }
+
+    public ConflictType(@NotNull TextDiffType type, boolean leftChange, boolean rightChange) {
+      myType = type;
+      myLeftChange = leftChange;
+      myRightChange = rightChange;
+    }
+
+    @NotNull
+    public TextDiffType getDiffType() {
+      return myType;
+    }
+
+    public boolean isLeftChange() {
+      return myLeftChange;
+    }
+
+    public boolean isRightChange() {
+      return myRightChange;
+    }
+
+    public boolean isChange(@NotNull Side side) {
+      return side.isLeft() ? myLeftChange : myRightChange;
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/tools/simple/ThreesideTextDiffViewerEx.java

@@ -0,0 +1,461 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.diff.tools.simple;
+
+import com.intellij.diff.DiffContext;
+import com.intellij.diff.fragments.MergeLineFragment;
+import com.intellij.diff.requests.ContentDiffRequest;
+import com.intellij.diff.tools.util.*;
+import com.intellij.diff.tools.util.base.TextDiffViewerUtil;
+import com.intellij.diff.tools.util.side.ThreesideTextDiffViewer;
+import com.intellij.diff.util.*;
+import com.intellij.diff.util.DiffDividerDrawUtil.DividerPaintable;
+import com.intellij.diff.util.DiffUserDataKeysEx.ScrollToPolicy;
+import com.intellij.openapi.Disposable;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.diff.DiffBundle;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.editor.event.DocumentEvent;
+import com.intellij.openapi.editor.ex.EditorEx;
+import com.intellij.openapi.util.UserDataHolder;
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.util.Function;
+import com.intellij.util.ui.ButtonlessScrollBarUI;
+import org.jetbrains.annotations.CalledInAwt;
+import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.awt.*;
+import java.util.Iterator;
+import java.util.List;
+
+public abstract class ThreesideTextDiffViewerEx extends ThreesideTextDiffViewer {
+  public static final Logger LOG = Logger.getInstance(ThreesideTextDiffViewerEx.class);
+
+  @NotNull private final SyncScrollSupport.SyncScrollable mySyncScrollable1;
+  @NotNull private final SyncScrollSupport.SyncScrollable mySyncScrollable2;
+
+  @NotNull protected final PrevNextDifferenceIterable myPrevNextDifferenceIterable;
+  @NotNull protected final MyStatusPanel myStatusPanel;
+
+  @NotNull protected final MyFoldingModel myFoldingModel;
+  @NotNull protected final MyInitialScrollHelper myInitialScrollHelper = new MyInitialScrollHelper();
+
+  private int myChangesCount = -1;
+  private int myConflictsCount = -1;
+
+  public ThreesideTextDiffViewerEx(@NotNull DiffContext context, @NotNull ContentDiffRequest request) {
+    super(context, request);
+
+    mySyncScrollable1 = new MySyncScrollable(Side.LEFT);
+    mySyncScrollable2 = new MySyncScrollable(Side.RIGHT);
+    myPrevNextDifferenceIterable = new MyPrevNextDifferenceIterable();
+    myStatusPanel = new MyStatusPanel();
+    myFoldingModel = new MyFoldingModel(getEditors().toArray(new EditorEx[3]), this);
+  }
+
+  @Override
+  @CalledInAwt
+  protected void onInit() {
+    super.onInit();
+    myContentPanel.setPainter(new MyDividerPainter(Side.LEFT), Side.LEFT);
+    myContentPanel.setPainter(new MyDividerPainter(Side.RIGHT), Side.RIGHT);
+    myContentPanel.setScrollbarPainter(new MyScrollbarPainter());
+  }
+
+  @Override
+  @CalledInAwt
+  protected void onDispose() {
+    destroyChangedBlocks();
+    super.onDispose();
+  }
+
+  @Override
+  @CalledInAwt
+  protected void processContextHints() {
+    super.processContextHints();
+    myInitialScrollHelper.processContext(myRequest);
+  }
+
+  @Override
+  @CalledInAwt
+  protected void updateContextHints() {
+    super.updateContextHints();
+    myFoldingModel.updateContext(myRequest, getFoldingModelSettings());
+    myInitialScrollHelper.updateContext(myRequest);
+  }
+
+  //
+  // Diff
+  //
+
+  @NotNull
+  public FoldingModelSupport.Settings getFoldingModelSettings() {
+    return TextDiffViewerUtil.getFoldingModelSettings(myContext);
+  }
+
+  @NotNull
+  protected Runnable applyNotification(@Nullable final JComponent notification) {
+    return new Runnable() {
+      @Override
+      public void run() {
+        clearDiffPresentation();
+        if (notification != null) myPanel.addNotification(notification);
+      }
+    };
+  }
+
+  protected void clearDiffPresentation() {
+    myStatusPanel.setBusy(false);
+    myPanel.resetNotifications();
+    destroyChangedBlocks();
+
+    myContentPanel.repaintDividers();
+    myStatusPanel.update();
+  }
+
+  protected void destroyChangedBlocks() {
+    myFoldingModel.destroy();
+  }
+
+  //
+  // Impl
+  //
+
+  @Override
+  protected void onDocumentChange(@NotNull DocumentEvent e) {
+    super.onDocumentChange(e);
+    myFoldingModel.onDocumentChanged(e);
+  }
+
+  @CalledInAwt
+  protected boolean doScrollToChange(@NotNull ScrollToPolicy scrollToPolicy) {
+    ThreesideDiffChangeBase targetChange = scrollToPolicy.select(getChanges());
+    if (targetChange == null) return false;
+
+    doScrollToChange(targetChange, false);
+    return true;
+  }
+
+  protected void doScrollToChange(@NotNull ThreesideDiffChangeBase change, boolean animated) {
+    int[] startLines = new int[3];
+    int[] endLines = new int[3];
+
+    for (int i = 0; i < 3; i++) {
+      ThreeSide side = ThreeSide.fromIndex(i);
+      startLines[i] = change.getStartLine(side);
+      endLines[i] = change.getEndLine(side);
+      DiffUtil.moveCaret(getEditor(side), startLines[i]);
+    }
+
+    getSyncScrollSupport().makeVisible(getCurrentSide(), startLines, endLines, animated);
+  }
+
+  //
+  // Counters
+  //
+
+  public int getChangesCount() {
+    return myChangesCount;
+  }
+
+  public int getConflictsCount() {
+    return myConflictsCount;
+  }
+
+  protected void resetChangeCounters() {
+    myChangesCount = 0;
+    myConflictsCount = 0;
+  }
+
+  protected void onChangeAdded(@NotNull ThreesideDiffChangeBase change) {
+    if (change.isConflict()) {
+      myConflictsCount++;
+    }
+    else {
+      myChangesCount++;
+    }
+    myStatusPanel.update();
+  }
+
+  protected void onChangeRemoved(@NotNull ThreesideDiffChangeBase change) {
+    if (change.isConflict()) {
+      myConflictsCount--;
+    }
+    else {
+      myChangesCount--;
+    }
+    myStatusPanel.update();
+  }
+
+  //
+  // Getters
+  //
+
+  @NotNull
+  protected abstract DividerPaintable getDividerPaintable(@NotNull Side side);
+
+  /*
+   * Some changes (ex: applied ones) can be excluded from general processing, but should be painted/used for synchronized scrolling
+   */
+  @NotNull
+  protected List<? extends ThreesideDiffChangeBase> getAllChanges() {
+    return getChanges();
+  }
+
+  @NotNull
+  protected abstract List<? extends ThreesideDiffChangeBase> getChanges();
+
+  @NotNull
+  @Override
+  protected SyncScrollSupport.SyncScrollable getSyncScrollable(@NotNull Side side) {
+    return side.select(mySyncScrollable1, mySyncScrollable2);
+  }
+
+  @NotNull
+  @Override
+  protected JComponent getStatusPanel() {
+    return myStatusPanel;
+  }
+
+  @NotNull
+  public SyncScrollSupport.ThreesideSyncScrollSupport getSyncScrollSupport() {
+    //noinspection ConstantConditions
+    return mySyncScrollSupport;
+  }
+
+  //
+  // Misc
+  //
+
+  @Nullable
+  @CalledInAwt
+  protected ThreesideDiffChangeBase getSelectedChange(@NotNull ThreeSide side) {
+    int caretLine = getEditor(side).getCaretModel().getLogicalPosition().line;
+
+    for (ThreesideDiffChangeBase change : getChanges()) {
+      int line1 = change.getStartLine(side);
+      int line2 = change.getEndLine(side);
+
+      if (DiffUtil.isSelectedByLine(caretLine, line1, line2)) return change;
+    }
+    return null;
+  }
+
+  //
+  // Actions
+  //
+
+  protected class MyPrevNextDifferenceIterable extends PrevNextDifferenceIterableBase<ThreesideDiffChangeBase> {
+    @NotNull
+    @Override
+    protected List<? extends ThreesideDiffChangeBase> getChanges() {
+      return ThreesideTextDiffViewerEx.this.getChanges();
+    }
+
+    @NotNull
+    @Override
+    protected EditorEx getEditor() {
+      return getCurrentEditor();
+    }
+
+    @Override
+    protected int getStartLine(@NotNull ThreesideDiffChangeBase change) {
+      return change.getStartLine(getCurrentSide());
+    }
+
+    @Override
+    protected int getEndLine(@NotNull ThreesideDiffChangeBase change) {
+      return change.getEndLine(getCurrentSide());
+    }
+
+    @Override
+    protected void scrollToChange(@NotNull ThreesideDiffChangeBase change) {
+      doScrollToChange(change, true);
+    }
+  }
+
+  protected class MyToggleExpandByDefaultAction extends TextDiffViewerUtil.ToggleExpandByDefaultAction {
+    public MyToggleExpandByDefaultAction() {
+      super(getTextSettings());
+    }
+
+    @Override
+    protected void expandAll(boolean expand) {
+      myFoldingModel.expandAll(expand);
+    }
+  }
+
+  //
+  // Helpers
+  //
+
+  @Nullable
+  @Override
+  public Object getData(@NonNls String dataId) {
+    if (DiffDataKeys.PREV_NEXT_DIFFERENCE_ITERABLE.is(dataId)) {
+      return myPrevNextDifferenceIterable;
+    }
+    else if (DiffDataKeys.CURRENT_CHANGE_RANGE.is(dataId)) {
+      ThreesideDiffChangeBase change = getSelectedChange(getCurrentSide());
+      if (change != null) {
+        return new LineRange(change.getStartLine(getCurrentSide()), change.getEndLine(getCurrentSide()));
+      }
+    }
+    return super.getData(dataId);
+  }
+
+  protected class MySyncScrollable extends BaseSyncScrollable {
+    @NotNull private final Side mySide;
+
+    public MySyncScrollable(@NotNull Side side) {
+      mySide = side;
+    }
+
+    @Override
+    public boolean isSyncScrollEnabled() {
+      return getTextSettings().isEnableSyncScroll();
+    }
+
+    @Override
+    protected void processHelper(@NotNull ScrollHelper helper) {
+      ThreeSide left = mySide.select(ThreeSide.LEFT, ThreeSide.BASE);
+      ThreeSide right = mySide.select(ThreeSide.BASE, ThreeSide.RIGHT);
+
+      if (!helper.process(0, 0)) return;
+      for (ThreesideDiffChangeBase diffChange : getAllChanges()) {
+        if (!helper.process(diffChange.getStartLine(left), diffChange.getStartLine(right))) return;
+        if (!helper.process(diffChange.getEndLine(left), diffChange.getEndLine(right))) return;
+      }
+      helper.process(getEditor(left).getDocument().getLineCount(), getEditor(right).getDocument().getLineCount());
+    }
+  }
+
+  protected class MyDividerPainter implements DiffSplitter.Painter {
+    @NotNull private final Side mySide;
+    @NotNull private final DividerPaintable myPaintable;
+
+    public MyDividerPainter(@NotNull Side side) {
+      mySide = side;
+      myPaintable = getDividerPaintable(side);
+    }
+
+    @Override
+    public void paint(@NotNull Graphics g, @NotNull JComponent divider) {
+      Graphics2D gg = DiffDividerDrawUtil.getDividerGraphics(g, divider, getEditor(ThreeSide.BASE).getComponent());
+
+      gg.setColor(DiffDrawUtil.getDividerColor(getEditor(ThreeSide.BASE)));
+      gg.fill(gg.getClipBounds());
+
+      Editor editor1 = mySide.select(getEditor(ThreeSide.LEFT), getEditor(ThreeSide.BASE));
+      Editor editor2 = mySide.select(getEditor(ThreeSide.BASE), getEditor(ThreeSide.RIGHT));
+
+      //DividerPolygonUtil.paintSimplePolygons(gg, divider.getWidth(), editor1, editor2, myPaintable);
+      DiffDividerDrawUtil.paintPolygons(gg, divider.getWidth(), editor1, editor2, myPaintable);
+
+      myFoldingModel.paintOnDivider(gg, divider, mySide);
+
+      gg.dispose();
+    }
+  }
+
+  protected class MyScrollbarPainter implements ButtonlessScrollBarUI.ScrollbarRepaintCallback {
+    @NotNull private final DividerPaintable myPaintable = getDividerPaintable(Side.RIGHT);
+
+    @Override
+    public void call(Graphics g) {
+      EditorEx editor1 = getEditor(ThreeSide.BASE);
+      EditorEx editor2 = getEditor(ThreeSide.RIGHT);
+
+      int width = editor1.getScrollPane().getVerticalScrollBar().getWidth();
+      DiffDividerDrawUtil.paintPolygonsOnScrollbar((Graphics2D)g, width, editor1, editor2, myPaintable);
+
+      myFoldingModel.paintOnScrollbar((Graphics2D)g, width);
+    }
+  }
+
+  protected class MyStatusPanel extends StatusPanel {
+    @Nullable
+    @Override
+    protected String getMessage() {
+      if (myChangesCount < 0 || myConflictsCount < 0) return null;
+      if (myChangesCount == 0 && myConflictsCount == 0) {
+        return DiffBundle.message("merge.dialog.all.conflicts.resolved.message.text");
+      }
+      return makeCounterWord(myChangesCount, "change") + ". " + makeCounterWord(myConflictsCount, "conflict");
+    }
+
+    @NotNull
+    private String makeCounterWord(int number, @NotNull String word) {
+      if (number == 0) {
+        return "No " + StringUtil.pluralize(word);
+      }
+      return number + " " + StringUtil.pluralize(word, number);
+    }
+  }
+
+  protected static class MyFoldingModel extends FoldingModelSupport {
+    private final MyPaintable myPaintable1 = new MyPaintable(0, 1);
+    private final MyPaintable myPaintable2 = new MyPaintable(1, 2);
+
+    public MyFoldingModel(@NotNull EditorEx[] editors, @NotNull Disposable disposable) {
+      super(editors, disposable);
+      assert editors.length == 3;
+    }
+
+    public void install(@Nullable List<MergeLineFragment> fragments,
+                        @NotNull UserDataHolder context,
+                        @NotNull FoldingModelSupport.Settings settings) {
+      Iterator<int[]> it = map(fragments, new Function<MergeLineFragment, int[]>() {
+        @Override
+        public int[] fun(MergeLineFragment fragment) {
+          return new int[]{
+            fragment.getStartLine(ThreeSide.LEFT),
+            fragment.getEndLine(ThreeSide.LEFT),
+            fragment.getStartLine(ThreeSide.BASE),
+            fragment.getEndLine(ThreeSide.BASE),
+            fragment.getStartLine(ThreeSide.RIGHT),
+            fragment.getEndLine(ThreeSide.RIGHT)};
+        }
+      });
+      install(it, context, settings);
+    }
+
+    public void paintOnDivider(@NotNull Graphics2D gg, @NotNull Component divider, @NotNull Side side) {
+      MyPaintable paintable = side.select(myPaintable1, myPaintable2);
+      paintable.paintOnDivider(gg, divider);
+    }
+
+    public void paintOnScrollbar(@NotNull Graphics2D gg, int width) {
+      myPaintable2.paintOnScrollbar(gg, width);
+    }
+  }
+
+  protected class MyInitialScrollHelper extends MyInitialScrollPositionHelper {
+    @Override
+    protected boolean doScrollToChange() {
+      if (myScrollToChange == null) return false;
+      return ThreesideTextDiffViewerEx.this.doScrollToChange(myScrollToChange);
+    }
+
+    @Override
+    protected boolean doScrollToFirstChange() {
+      return ThreesideTextDiffViewerEx.this.doScrollToChange(ScrollToPolicy.FIRST_CHANGE);
+    }
+  }
+}

platform/diff-impl/src/com/intellij/diff/tools/util/PrevNextDifferenceIterableBase.java

@@ -22,7 +22,7 @@ import java.util.List;
 
 public abstract class PrevNextDifferenceIterableBase<T> implements PrevNextDifferenceIterable {
   @NotNull
-  protected abstract List<T> getChanges();
+  protected abstract List<? extends T> getChanges();
 
   @NotNull
   protected abstract EditorEx getEditor();
@@ -35,7 +35,7 @@ public abstract class PrevNextDifferenceIterableBase<T> implements PrevNextDiffe
 
   @Override
   public boolean canGoNext() {
-    List<T> changes = getChanges();
+    List<? extends T> changes = getChanges();
     if (changes.isEmpty()) return false;
 
     EditorEx editor = getEditor();
@@ -50,7 +50,7 @@ public abstract class PrevNextDifferenceIterableBase<T> implements PrevNextDiffe
 
   @Override
   public void goNext() {
-    List<T> changes = getChanges();
+    List<? extends T> changes = getChanges();
     int line = getEditor().getCaretModel().getLogicalPosition().line;
 
     T next = null;
@@ -68,7 +68,7 @@ public abstract class PrevNextDifferenceIterableBase<T> implements PrevNextDiffe
 
   @Override
   public boolean canGoPrev() {
-    List<T> changes = getChanges();
+    List<? extends T> changes = getChanges();
     if (changes.isEmpty()) return false;
 
     int line = getEditor().getCaretModel().getLogicalPosition().line;
@@ -83,7 +83,7 @@ public abstract class PrevNextDifferenceIterableBase<T> implements PrevNextDiffe
 
   @Override
   public void goPrev() {
-    List<T> changes = getChanges();
+    List<? extends T> changes = getChanges();
     int line = getEditor().getCaretModel().getLogicalPosition().line;
 
     T prev = null;

platform/diff-impl/src/com/intellij/diff/tools/util/SyncScrollSupport.java

@@ -15,8 +15,8 @@
  */
 package com.intellij.diff.tools.util;
 
-import com.intellij.diff.util.IntPair;
 import com.intellij.diff.util.Side;
+import com.intellij.diff.util.ThreeSide;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.LogicalPosition;
@@ -24,7 +24,7 @@ import com.intellij.openapi.editor.ScrollingModel;
 import com.intellij.openapi.editor.event.VisibleAreaEvent;
 import com.intellij.openapi.editor.event.VisibleAreaListener;
 import com.intellij.openapi.editor.ex.EditorEx;
-import gnu.trove.TIntFunction;
+import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.CalledInAwt;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -44,37 +44,31 @@ public class SyncScrollSupport {
     int transfer(@NotNull Side baseSide, int line);
   }
 
-  public static class TwosideSyncScrollSupport {
-    @NotNull private final Editor myEditor1;
-    @NotNull private final Editor myEditor2;
+  public static class TwosideSyncScrollSupport extends SyncScrollSupportBase {
+    @NotNull private final List<? extends Editor> myEditors;
     @NotNull private final SyncScrollable myScrollable;
 
-    @NotNull private final MyScrollHelper myHelper1;
-    @NotNull private final MyScrollHelper myHelper2;
-
-    private boolean myDisabled = false;
-    private boolean myDuringSyncScroll = false;
+    @NotNull private final ScrollHelper myHelper1;
+    @NotNull private final ScrollHelper myHelper2;
 
     public TwosideSyncScrollSupport(@NotNull List<? extends Editor> editors, @NotNull SyncScrollable scrollable) {
-      this(Side.LEFT.select(editors), Side.RIGHT.select(editors), scrollable);
-    }
-
-    public TwosideSyncScrollSupport(@NotNull Editor editor1, @NotNull Editor editor2, @NotNull SyncScrollable scrollable) {
-      myEditor1 = editor1;
-      myEditor2 = editor2;
+      myEditors = editors;
       myScrollable = scrollable;
 
-      myHelper1 = create(myEditor1, myEditor2, myScrollable, Side.LEFT);
-      myHelper2 = create(myEditor2, myEditor1, myScrollable, Side.RIGHT);
+      myHelper1 = create(Side.LEFT);
+      myHelper2 = create(Side.RIGHT);
     }
 
-    public boolean isDuringSyncScroll() {
-      return myDuringSyncScroll;
+    @Override
+    @NotNull
+    protected List<? extends Editor> getEditors() {
+      return myEditors;
     }
 
-    public void setDisabled(boolean value) {
-      if (myDisabled == value) LOG.warn(new Throwable("myDisabled == value: " + myDisabled + " - " + value));
-      myDisabled = value;
+    @Override
+    @NotNull
+    protected List<? extends ScrollHelper> getScrollHelpers() {
+      return ContainerUtil.list(myHelper1, myHelper2);
     }
 
     @NotNull
@@ -83,41 +77,176 @@ public class SyncScrollSupport {
     }
 
     public void visibleAreaChanged(VisibleAreaEvent e) {
-      if (!myScrollable.isSyncScrollEnabled() || myDuringSyncScroll || myDisabled) return;
+      if (!myScrollable.isSyncScrollEnabled() || isDuringSyncScroll()) return;
 
-      myDuringSyncScroll = true;
+      enterDisableScrollSection();
       try {
-        if (e.getEditor() == myEditor1) {
+        if (e.getEditor() == Side.LEFT.select(myEditors)) {
           myHelper1.visibleAreaChanged(e);
         }
-        else if (e.getEditor() == myEditor2) {
+        else if (e.getEditor() == Side.RIGHT.select(myEditors)) {
           myHelper2.visibleAreaChanged(e);
         }
       }
       finally {
-        myDuringSyncScroll = false;
+        exitDisableScrollSection();
       }
     }
 
     public void makeVisible(@NotNull Side masterSide,
                             int startLine1, int endLine1, int startLine2, int endLine2,
                             final boolean animate) {
-      Side slaveSide = masterSide.other();
+      doMakeVisible(masterSide.getIndex(), new int[]{startLine1, startLine2}, new int[]{endLine1, endLine2}, animate);
+    }
 
-      final IntPair offsets = getTargetOffsets(myEditor1, myEditor2, startLine1, endLine1, startLine2, endLine2);
+    @NotNull
+    private ScrollHelper create(@NotNull Side side) {
+      return ScrollHelper.create(myEditors, side.getIndex(), side.other().getIndex(), myScrollable, side);
+    }
+  }
 
-      final Editor masterEditor = masterSide.select(myEditor1, myEditor2);
-      final Editor slaveEditor = slaveSide.select(myEditor1, myEditor2);
+  public static class ThreesideSyncScrollSupport extends SyncScrollSupportBase {
+    @NotNull private final List<? extends Editor> myEditors;
+    @NotNull private final SyncScrollable myScrollable12;
+    @NotNull private final SyncScrollable myScrollable23;
 
-      final int masterOffset = masterSide.select(offsets.val1, offsets.val2);
-      final int slaveOffset = slaveSide.select(offsets.val1, offsets.val2);
+    @NotNull private final ScrollHelper myHelper12;
+    @NotNull private final ScrollHelper myHelper21;
+    @NotNull private final ScrollHelper myHelper23;
+    @NotNull private final ScrollHelper myHelper32;
 
-      int startOffset1 = myEditor1.getScrollingModel().getVisibleArea().y;
-      int startOffset2 = myEditor2.getScrollingModel().getVisibleArea().y;
-      final int masterStartOffset = masterSide.select(startOffset1, startOffset2);
+    public ThreesideSyncScrollSupport(@NotNull List<? extends Editor> editors,
+                                      @NotNull SyncScrollable scrollable12,
+                                      @NotNull SyncScrollable scrollable23) {
+      assert editors.size() == 3;
 
-      myHelper1.setAnchor(startOffset1, offsets.val1, startOffset2, offsets.val2);
-      myHelper2.setAnchor(startOffset2, offsets.val2, startOffset1, offsets.val1);
+      myEditors = editors;
+      myScrollable12 = scrollable12;
+      myScrollable23 = scrollable23;
+
+      myHelper12 = create(ThreeSide.LEFT, ThreeSide.BASE);
+      myHelper21 = create(ThreeSide.BASE, ThreeSide.LEFT);
+
+      myHelper23 = create(ThreeSide.BASE, ThreeSide.RIGHT);
+      myHelper32 = create(ThreeSide.RIGHT, ThreeSide.BASE);
+    }
+
+    @Override
+    @NotNull
+    protected List<? extends Editor> getEditors() {
+      return myEditors;
+    }
+
+    @Override
+    @NotNull
+    protected List<? extends ScrollHelper> getScrollHelpers() {
+      return ContainerUtil.list(myHelper12, myHelper21, myHelper23, myHelper32);
+    }
+
+    public void visibleAreaChanged(VisibleAreaEvent e) {
+      if (isDuringSyncScroll()) return;
+
+      enterDisableScrollSection();
+      try {
+        if (e.getEditor() == ThreeSide.LEFT.select(myEditors)) {
+          if (myScrollable12.isSyncScrollEnabled()) {
+            myHelper12.visibleAreaChanged(e);
+            if (myScrollable23.isSyncScrollEnabled()) myHelper23.visibleAreaChanged(e);
+          }
+        }
+        else if (e.getEditor() == ThreeSide.BASE.select(myEditors)) {
+          if (myScrollable12.isSyncScrollEnabled()) myHelper21.visibleAreaChanged(e);
+          if (myScrollable23.isSyncScrollEnabled()) myHelper23.visibleAreaChanged(e);
+        }
+        else if (e.getEditor() == ThreeSide.RIGHT.select(myEditors)) {
+          if (myScrollable23.isSyncScrollEnabled()) {
+            myHelper32.visibleAreaChanged(e);
+            if (myScrollable12.isSyncScrollEnabled()) myHelper21.visibleAreaChanged(e);
+          }
+        }
+      }
+      finally {
+        exitDisableScrollSection();
+      }
+    }
+
+    public void makeVisible(@NotNull ThreeSide masterSide, int[] startLines, int[] endLines, boolean animate) {
+      doMakeVisible(masterSide.getIndex(), startLines, endLines, animate);
+    }
+
+    @NotNull
+    private ScrollHelper create(@NotNull ThreeSide master, @NotNull ThreeSide slave) {
+      assert master != slave;
+      assert master == ThreeSide.BASE || slave == ThreeSide.BASE;
+
+      boolean leftSide = master == ThreeSide.LEFT || slave == ThreeSide.LEFT;
+      SyncScrollable scrollable = leftSide ? myScrollable12 : myScrollable23;
+
+      Side side;
+      if (leftSide) {
+        // LEFT - BASE -> LEFT
+        // BASE - LEFT -> RIGHT
+        side = Side.fromLeft(master == ThreeSide.LEFT);
+      }
+      else {
+        // BASE - RIGHT -> LEFT
+        // RIGHT - BASE -> RIGHT
+        side = Side.fromLeft(master == ThreeSide.BASE);
+      }
+
+      return ScrollHelper.create(myEditors, master.getIndex(), slave.getIndex(), scrollable, side);
+    }
+  }
+
+  //
+  // Impl
+  //
+
+  private abstract static class SyncScrollSupportBase {
+    private int myDuringSyncScrollDepth = 0;
+
+    public boolean isDuringSyncScroll() {
+      return myDuringSyncScrollDepth > 0;
+    }
+
+    public void enterDisableScrollSection() {
+      myDuringSyncScrollDepth++;
+    }
+
+    public void exitDisableScrollSection() {
+      myDuringSyncScrollDepth--;
+      assert myDuringSyncScrollDepth >= 0;
+    }
+
+    @NotNull
+    protected abstract List<? extends Editor> getEditors();
+
+    @NotNull
+    protected abstract List<? extends ScrollHelper> getScrollHelpers();
+
+    protected void doMakeVisible(final int masterIndex, int[] startLines, int[] endLines, final boolean animate) {
+      final List<? extends Editor> editors = getEditors();
+      final List<? extends ScrollHelper> helpers = getScrollHelpers();
+
+      final int count = editors.size();
+      assert startLines.length == count;
+      assert endLines.length == count;
+
+      final int[] offsets = getTargetOffsets(editors.toArray(new Editor[count]), startLines, endLines);
+
+      final int[] startOffsets = new int[count];
+      for (int i = 0; i < count; i++) {
+        startOffsets[i] = editors.get(i).getScrollingModel().getVisibleArea().y;
+      }
+
+      final Editor masterEditor = editors.get(masterIndex);
+      final int masterOffset = offsets[masterIndex];
+      final int masterStartOffset = startOffsets[masterIndex];
+
+      for (ScrollHelper helper : helpers) {
+        helper.setAnchor(startOffsets[helper.getMasterIndex()], offsets[helper.getMasterIndex()],
+                         startOffsets[helper.getSlaveIndex()], offsets[helper.getSlaveIndex()]);
+      }
 
       doScrollHorizontally(masterEditor, 0, false); // animation will be canceled by "scroll vertically" anyway
       doScrollVertically(masterEditor, masterOffset, animate);
@@ -125,117 +254,64 @@ public class SyncScrollSupport {
       masterEditor.getScrollingModel().runActionOnScrollingFinished(new Runnable() {
         @Override
         public void run() {
-          myHelper1.removeAnchor();
-          myHelper2.removeAnchor();
+          for (ScrollHelper helper : helpers) {
+            helper.removeAnchor();
+          }
 
           int masterFinalOffset = masterEditor.getScrollingModel().getVisibleArea().y;
-          int slaveFinalOffset = slaveEditor.getScrollingModel().getVisibleArea().y;
-          if (slaveFinalOffset != slaveOffset) {
-            myDuringSyncScroll = true;
+          boolean animateSlaves = animate && masterFinalOffset == masterStartOffset;
+          for (int i = 0; i < count; i++) {
+            if (i == masterIndex) continue;
+            Editor editor = editors.get(i);
 
-            doScrollVertically(slaveEditor, slaveOffset, animate && masterFinalOffset == masterStartOffset);
+            int finalOffset = editor.getScrollingModel().getVisibleArea().y;
+            if (finalOffset != offsets[i]) {
+              enterDisableScrollSection();
 
-            slaveEditor.getScrollingModel().runActionOnScrollingFinished(new Runnable() {
-              @Override
-              public void run() {
-                myDuringSyncScroll = false;
-              }
-            });
+              doScrollVertically(editor, offsets[i], animateSlaves);
+
+              editor.getScrollingModel().runActionOnScrollingFinished(new Runnable() {
+                @Override
+                public void run() {
+                  exitDisableScrollSection();
+                }
+              });
+            }
           }
         }
       });
     }
   }
 
-  public static class ThreesideSyncScrollSupport {
+  private static abstract class ScrollHelper implements VisibleAreaListener {
     @NotNull private final List<? extends Editor> myEditors;
-    @NotNull private final SyncScrollable myScrollable1;
-    @NotNull private final SyncScrollable myScrollable2;
-
-    @NotNull private final MyScrollHelper myHelper11;
-    @NotNull private final MyScrollHelper myHelper12;
-    @NotNull private final MyScrollHelper myHelper21;
-    @NotNull private final MyScrollHelper myHelper22;
-
-    private boolean myDisabled = false;
-    private boolean myDuringSyncScroll = false;
-
-    public ThreesideSyncScrollSupport(@NotNull List<? extends Editor> editors,
-                                      @NotNull SyncScrollable scrollable1,
-                                      @NotNull SyncScrollable scrollable2) {
-      assert editors.size() == 3;
-
-      myEditors = editors;
-      myScrollable1 = scrollable1;
-      myScrollable2 = scrollable2;
-
-      myHelper11 = create(editors.get(0), editors.get(1), myScrollable1, Side.LEFT);
-      myHelper12 = create(editors.get(1), editors.get(0), myScrollable1, Side.RIGHT);
-
-      myHelper21 = create(editors.get(1), editors.get(2), myScrollable2, Side.LEFT);
-      myHelper22 = create(editors.get(2), editors.get(1), myScrollable2, Side.RIGHT);
-    }
-
-    public void setDisabled(boolean value) {
-      if (myDisabled == value) LOG.warn(new Throwable("myDisabled == value: " + myDisabled + " - " + value));
-      myDisabled = value;
-    }
-
-    public void visibleAreaChanged(VisibleAreaEvent e) {
-      if (myDuringSyncScroll || myDisabled) return;
-
-      myDuringSyncScroll = true;
-      try {
-        if (e.getEditor() == myEditors.get(0)) {
-          if (myScrollable1.isSyncScrollEnabled()) myHelper11.visibleAreaChanged(e);
-          if (myScrollable1.isSyncScrollEnabled() && myScrollable2.isSyncScrollEnabled()) myHelper21.visibleAreaChanged(e);
-        }
-        else if (e.getEditor() == myEditors.get(1)) {
-          if (myScrollable1.isSyncScrollEnabled()) myHelper12.visibleAreaChanged(e);
-          if (myScrollable2.isSyncScrollEnabled()) myHelper21.visibleAreaChanged(e);
-        }
-        else if (e.getEditor() == myEditors.get(2)) {
-          if (myScrollable2.isSyncScrollEnabled()) myHelper22.visibleAreaChanged(e);
-          if (myScrollable2.isSyncScrollEnabled() && myScrollable1.isSyncScrollEnabled()) myHelper12.visibleAreaChanged(e);
-        }
-      }
-      finally {
-        myDuringSyncScroll = false;
-      }
-    }
-  }
-
-  @NotNull
-  private static MyScrollHelper create(@NotNull Editor master,
-                                       @NotNull Editor slave,
-                                       @NotNull final SyncScrollable scrollable,
-                                       @NotNull final Side side) {
-    return new MyScrollHelper(master, slave, new TIntFunction() {
-      @Override
-      public int execute(int value) {
-        return scrollable.transfer(side, value);
-      }
-    });
-  }
-
-  //
-  // Impl
-  //
-
-
-  private static class MyScrollHelper implements VisibleAreaListener {
-    @NotNull private final Editor myMaster;
-    @NotNull private final Editor mySlave;
-    @NotNull private final TIntFunction myConvertor;
+    private final int myMasterIndex;
+    private final int mySlaveIndex;
 
     @Nullable private Anchor myAnchor;
 
-    public MyScrollHelper(@NotNull Editor master, @NotNull Editor slave, @NotNull TIntFunction convertor) {
-      myMaster = master;
-      mySlave = slave;
-      myConvertor = convertor;
+    public ScrollHelper(@NotNull List<? extends Editor> editors, int masterIndex, int slaveIndex) {
+      myEditors = editors;
+      myMasterIndex = masterIndex;
+      mySlaveIndex = slaveIndex;
     }
 
+    @NotNull
+    public static ScrollHelper create(@NotNull List<? extends Editor> editors,
+                                      int masterIndex,
+                                      int slaveIndex,
+                                      @NotNull final SyncScrollable scrollable,
+                                      @NotNull final Side side) {
+      return new ScrollHelper(editors, masterIndex, slaveIndex) {
+        @Override
+        protected int convertLine(int value) {
+          return scrollable.transfer(side, value);
+        }
+      };
+    }
+
+    protected abstract int convertLine(int value);
+
     public void setAnchor(int masterStartOffset, int masterEndOffset, int slaveStartOffset, int slaveEndOffset) {
       myAnchor = new Anchor(masterStartOffset, masterEndOffset, slaveStartOffset, slaveEndOffset);
     }
@@ -254,20 +330,38 @@ public class SyncScrollSupport {
       if (newRectangle.y != oldRectangle.y) syncVerticalScroll(false);
     }
 
-    private void syncVerticalScroll(boolean animated) {
-      if (myMaster.getDocument().getTextLength() == 0) return;
+    public int getMasterIndex() {
+      return myMasterIndex;
+    }
 
-      Rectangle viewRect = myMaster.getScrollingModel().getVisibleArea();
+    public int getSlaveIndex() {
+      return mySlaveIndex;
+    }
+
+    @NotNull
+    public Editor getMaster() {
+      return myEditors.get(myMasterIndex);
+    }
+
+    @NotNull
+    public Editor getSlave() {
+      return myEditors.get(mySlaveIndex);
+    }
+
+    private void syncVerticalScroll(boolean animated) {
+      if (getMaster().getDocument().getTextLength() == 0) return;
+
+      Rectangle viewRect = getMaster().getScrollingModel().getVisibleArea();
       int middleY = viewRect.height / 3;
 
       int offset;
       if (myAnchor == null) {
-        LogicalPosition masterPos = myMaster.xyToLogicalPosition(new Point(viewRect.x, viewRect.y + middleY));
+        LogicalPosition masterPos = getMaster().xyToLogicalPosition(new Point(viewRect.x, viewRect.y + middleY));
         int masterCenterLine = masterPos.line;
-        int convertedCenterLine = myConvertor.execute(masterCenterLine);
+        int convertedCenterLine = convertLine(masterCenterLine);
 
-        Point point = mySlave.logicalPositionToXY(new LogicalPosition(convertedCenterLine, masterPos.column));
-        int correction = (viewRect.y + middleY) % myMaster.getLineHeight();
+        Point point = getSlave().logicalPositionToXY(new LogicalPosition(convertedCenterLine, masterPos.column));
+        int correction = (viewRect.y + middleY) % getMaster().getLineHeight();
         offset = point.y - middleY + correction;
       }
       else {
@@ -277,13 +371,13 @@ public class SyncScrollSupport {
         offset = myAnchor.slaveStartOffset + (int)((myAnchor.slaveEndOffset - myAnchor.slaveStartOffset) * progress);
       }
 
-      int deltaHeaderOffset = getHeaderOffset(mySlave) - getHeaderOffset(myMaster);
-      doScrollVertically(mySlave, offset + deltaHeaderOffset, animated);
+      int deltaHeaderOffset = getHeaderOffset(getSlave()) - getHeaderOffset(getMaster());
+      doScrollVertically(getSlave(), offset + deltaHeaderOffset, animated);
     }
 
     private void syncHorizontalScroll(boolean animated) {
-      int offset = myMaster.getScrollingModel().getVisibleArea().x;
-      doScrollHorizontally(mySlave, offset, animated);
+      int offset = getMaster().getScrollingModel().getVisibleArea().x;
+      doScrollHorizontally(getSlave(), offset, animated);
     }
   }
 
@@ -307,56 +401,83 @@ public class SyncScrollSupport {
   }
 
   @NotNull
-  private static IntPair getTargetOffsets(@NotNull Editor editor1, @NotNull Editor editor2,
-                                          int startLine1, int endLine1, int startLine2, int endLine2) {
-    int topOffset1 = editor1.logicalPositionToXY(new LogicalPosition(startLine1, 0)).y;
-    int bottomOffset1 = editor1.logicalPositionToXY(new LogicalPosition(endLine1 + 1, 0)).y;
-    int topOffset2 = editor2.logicalPositionToXY(new LogicalPosition(startLine2, 0)).y;
-    int bottomOffset2 = editor2.logicalPositionToXY(new LogicalPosition(endLine2 + 1, 0)).y;
+  private static int[] getTargetOffsets(@NotNull Editor editor1, @NotNull Editor editor2,
+                                        int startLine1, int endLine1, int startLine2, int endLine2) {
+    return getTargetOffsets(new Editor[]{editor1, editor2},
+                            new int[]{startLine1, startLine2},
+                            new int[]{endLine1, endLine2});
+  }
 
-    int rangeHeight1 = bottomOffset1 - topOffset1;
-    int rangeHeight2 = bottomOffset2 - topOffset2;
+  @NotNull
+  private static int[] getTargetOffsets(@NotNull Editor[] editors, int[] startLines, int[] endLines) {
+    int count = editors.length;
+    assert startLines.length == count;
+    assert endLines.length == count;
 
-    int gapLines1 = 2 * editor1.getLineHeight();
-    int gapLines2 = 2 * editor2.getLineHeight();
+    int[] topOffsets = new int[count];
+    int[] bottomOffsets = new int[count];
+    int[] rangeHeights = new int[count];
+    int[] gapLines = new int[count];
+    int[] editorHeights = new int[count];
+    int[] maximumOffsets = new int[count];
+    int[] topShifts = new int[count];
 
-    int editorHeight1 = editor1.getScrollingModel().getVisibleArea().height;
-    int editorHeight2 = editor2.getScrollingModel().getVisibleArea().height;
+    for (int i = 0; i < count; i++) {
+      topOffsets[i] = editors[i].logicalPositionToXY(new LogicalPosition(startLines[i], 0)).y;
+      bottomOffsets[i] = editors[i].logicalPositionToXY(new LogicalPosition(endLines[i] + 1, 0)).y;
+      rangeHeights[i] = bottomOffsets[i] - topOffsets[i];
 
-    int maximumOffset1 = ((EditorEx)editor1).getScrollPane().getVerticalScrollBar().getMaximum() - editorHeight1;
-    int maximumOffset2 = ((EditorEx)editor2).getScrollPane().getVerticalScrollBar().getMaximum() - editorHeight2;
+      gapLines[i] = 2 * editors[i].getLineHeight();
+      editorHeights[i] = editors[i].getScrollingModel().getVisibleArea().height;
 
-    // 'shift' here - distance between editor's top and first line of range
+      maximumOffsets[i] = ((EditorEx)editors[i]).getScrollPane().getVerticalScrollBar().getMaximum() - editorHeights[i];
 
-    // make whole range visible. If possible, locate it at 'center' (1/3 of height)
-    // If can't show whole range - show as much as we can
-    boolean canShow1 = 2 * gapLines1 + rangeHeight1 <= editorHeight1;
-    boolean canShow2 = 2 * gapLines2 + rangeHeight2 <= editorHeight2;
-    
-    int topShift1 = canShow1 ? Math.min(editorHeight1 - gapLines1 - rangeHeight1, editorHeight1 / 3) : gapLines1;
-    int topShift2 = canShow2 ? Math.min(editorHeight2 - gapLines2 - rangeHeight2, editorHeight2 / 3) : gapLines2;
+      // 'shift' here - distance between editor's top and first line of range
 
-    int topShift = Math.min(topShift1, topShift2);
+      // make whole range visible. If possible, locate it at 'center' (1/3 of height)
+      // If can't show whole range - show as much as we can
+      boolean canShow = 2 * gapLines[i] + rangeHeights[i] <= editorHeights[i];
+
+      topShifts[i] = canShow ? Math.min(editorHeights[i] - gapLines[i] - rangeHeights[i], editorHeights[i] / 3) : gapLines[i];
+    }
+
+    int topShift = min(topShifts);
 
     // check if we're at the top of file
-    topShift = Math.min(topShift, Math.min(topOffset1, topOffset2));
+    topShift = Math.min(topShift, min(topOffsets));
 
-    int offset1 = topOffset1 - topShift;
-    int offset2 = topOffset2 - topShift;
-    if (maximumOffset1 > offset1 && maximumOffset2 > offset2) return new IntPair(offset1, offset2);
+    int[] offsets = new int[count];
+    boolean haveEnoughSpace = true;
+    for (int i = 0; i < count; i++) {
+      offsets[i] = topOffsets[i] - topShift;
+      haveEnoughSpace &= maximumOffsets[i] > offsets[i];
+    }
+
+    if (haveEnoughSpace) return offsets;
 
     // One of the ranges is at end of file - we can't scroll where we want to.
-    topShift = Math.max(topOffset1 - maximumOffset1, topOffset2 - maximumOffset2);
+    topShift = 0;
+    for (int i = 0; i < count; i++) {
+      topShift = Math.max(topOffsets[i] - maximumOffsets[i], topShift);
+    }
 
-    // Try to show as much of range as we can (even if it breaks alignment)
-    offset1 = topOffset1 - topShift + Math.max(topShift + rangeHeight1 + gapLines1 - editorHeight1, 0);
-    offset2 = topOffset2 - topShift + Math.max(topShift + rangeHeight2 + gapLines2 - editorHeight2, 0);
+    for (int i = 0; i < count; i++) {
+      // Try to show as much of range as we can (even if it breaks alignment)
+      offsets[i] = topOffsets[i] - topShift + Math.max(topShift + rangeHeights[i] + gapLines[i] - editorHeights[i], 0);
 
-    // always show top of the range
-    offset1 = Math.min(offset1, topOffset1 - gapLines1);
-    offset2 = Math.min(offset2, topOffset2 - gapLines2);
+      // always show top of the range
+      offsets[i] = Math.min(offsets[i], topOffsets[i] - gapLines[i]);
+    }
 
-    return new IntPair(offset1, offset2);
+    return offsets;
+  }
+
+  private static int min(int[] values) {
+    int min = Integer.MAX_VALUE;
+    for (int value : values) {
+      if (value < min) min = value;
+    }
+    return min;
   }
 
   private static class Anchor {

platform/diff-impl/src/com/intellij/diff/tools/util/base/DiffPanelBase.java

@@ -18,21 +18,29 @@ package com.intellij.diff.tools.util.base;
 import com.intellij.diff.DiffContext;
 import com.intellij.openapi.actionSystem.DataProvider;
 import com.intellij.openapi.project.Project;
+import com.intellij.ui.components.panels.Wrapper;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import javax.swing.*;
 import java.awt.*;
+import java.util.ArrayList;
+import java.util.List;
 
 public abstract class DiffPanelBase extends JPanel implements DataProvider {
   @Nullable protected final Project myProject;
   @NotNull private final DataProvider myDataProvider;
   @NotNull protected final DiffContext myContext;
 
+  @NotNull private final List<JComponent> myPersistentNotifications = new ArrayList<JComponent>();
+
   @NotNull protected final JPanel myContentPanel;
   @NotNull protected final JPanel myNotificationsPanel;
 
+  @NotNull private final Wrapper myNorthPanel;
+  @NotNull private final Wrapper mySouthPanel;
+
   @NotNull protected final CardLayout myCardLayout;
 
   @NotNull protected String myCurrentCard;
@@ -51,23 +59,20 @@ public abstract class DiffPanelBase extends JPanel implements DataProvider {
     myNotificationsPanel = new JPanel();
     myNotificationsPanel.setLayout(new BoxLayout(myNotificationsPanel, BoxLayout.Y_AXIS));
 
+    myNorthPanel = new Wrapper();
+    mySouthPanel = new Wrapper();
+
     add(myContentPanel, BorderLayout.CENTER);
-
-    JComponent topPanel = createTopPanel();
-    if (topPanel != null) add(topPanel, BorderLayout.NORTH);
-
-    JComponent bottomPanel = createBottomPanel();
-    if (bottomPanel != null) add(bottomPanel, BorderLayout.SOUTH);
+    add(myNorthPanel, BorderLayout.NORTH);
+    add(mySouthPanel, BorderLayout.SOUTH);
   }
 
-  @Nullable
-  public JComponent createTopPanel() {
-    return null;
+  public void setTopPanel(@Nullable JComponent component) {
+    myNorthPanel.setContent(component);
   }
 
-  @Nullable
-  public JComponent createBottomPanel() {
-    return null;
+  public void setBottomPanel(@Nullable JComponent component) {
+    mySouthPanel.setContent(component);
   }
 
   protected void setCurrentCard(@NotNull String card) {
@@ -94,8 +99,25 @@ public abstract class DiffPanelBase extends JPanel implements DataProvider {
   // Notifications
   //
 
+  public void setPersistentNotifications(@NotNull List<JComponent> components) {
+    for (JComponent notification : myPersistentNotifications) {
+      myNotificationsPanel.remove(notification);
+    }
+
+    myPersistentNotifications.clear();
+    myPersistentNotifications.addAll(components);
+
+    for (JComponent notification : myPersistentNotifications) {
+      myNotificationsPanel.add(notification);
+    }
+    myNotificationsPanel.revalidate();
+  }
+
   public void resetNotifications() {
     myNotificationsPanel.removeAll();
+    for (JComponent notification : myPersistentNotifications) {
+      myNotificationsPanel.add(notification);
+    }
     myNotificationsPanel.revalidate();
   }
 

platform/diff-impl/src/com/intellij/diff/tools/util/base/DiffViewerBase.java

@@ -125,7 +125,7 @@ public abstract class DiffViewerBase implements DiffViewer, DataProvider {
   }
 
   @CalledInAwt
-  public final void rediff(boolean trySync) {
+  public void rediff(boolean trySync) {
     if (isDisposed()) return;
     abortRediff();
 

platform/diff-impl/src/com/intellij/diff/tools/util/side/OnesideDiffViewer.java

@@ -57,6 +57,12 @@ public abstract class OnesideDiffViewer<T extends EditorHolder> extends Listener
     myPanel = new SimpleDiffPanel(myContentPanel, this, context);
   }
 
+  @Override
+  protected void onInit() {
+    super.onInit();
+    myPanel.setPersistentNotifications(DiffUtil.getCustomNotifications(myContext, myRequest));
+  }
+
   @Override
   @CalledInAwt
   protected void onDispose() {

platform/diff-impl/src/com/intellij/diff/tools/util/side/ThreesideDiffViewer.java

@@ -66,6 +66,12 @@ public abstract class ThreesideDiffViewer<T extends EditorHolder> extends Listen
     myPanel = new SimpleDiffPanel(myContentPanel, this, context);
   }
 
+  @Override
+  protected void onInit() {
+    super.onInit();
+    myPanel.setPersistentNotifications(DiffUtil.getCustomNotifications(myContext, myRequest));
+  }
+
   @Override
   @CalledInAwt
   protected void onDispose() {