extract method: fix name conflicts at method call site

java/java-impl/src/com/intellij/psi/impl/source/codeStyle/JavaCodeStyleManagerImpl.java

@@ -891,8 +891,10 @@ public class JavaCodeStyleManagerImpl extends JavaCodeStyleManager {
             try {
               run.accept(new JavaRecursiveElementWalkingVisitor() {
                 @Override
-                public void visitAnonymousClass(final PsiAnonymousClass aClass) {
-                }
+                public void visitClass(final PsiClass aClass) {}
+
+                @Override
+                public void visitForeachStatement(PsiForeachStatement statement) {}
 
                 @Override public void visitVariable(PsiVariable variable) {
                   if (name1.equals(variable.getName())) {

java/java-impl/src/com/intellij/refactoring/extractMethod/ExtractMethodProcessor.java

@@ -760,8 +760,8 @@ public class ExtractMethodProcessor implements MatchProvider {
         CodeStyleManager.getInstance(myProject).reformat(ifStatement);
       }
       else if (myNotNullConditionalCheck) {
-        final String varName = myOutputVariable.getName();
-        declareVariableAtMethodCallLocation(varName, myReturnType instanceof PsiPrimitiveType ? ((PsiPrimitiveType)myReturnType).getBoxedType(myCodeFragmentMember) : myReturnType);
+        String varName = myOutputVariable.getName();
+        varName = declareVariableAtMethodCallLocation(varName, myReturnType instanceof PsiPrimitiveType ? ((PsiPrimitiveType)myReturnType).getBoxedType(myCodeFragmentMember) : myReturnType);
         addToMethodCallLocation(myElementFactory.createStatementFromText("if (" + varName + " != null) return " + varName + ";", null));
       }
       else if (myGenerateConditionalExit) {
@@ -903,12 +903,17 @@ public class ExtractMethodProcessor implements MatchProvider {
     declareVariableAtMethodCallLocation(name, myOutputVariable.getType());
   }
 
-  private void declareVariableAtMethodCallLocation(String name, PsiType type) {
+  private String declareVariableAtMethodCallLocation(String name, PsiType type) {
+    if (myControlFlowWrapper.getOutputVariables(false).length == 0) {
+      PsiElement lastStatement = myEnclosingBlockStatement != null ? myEnclosingBlockStatement : myElements[myElements.length - 1];
+      name = JavaCodeStyleManager.getInstance(myProject).suggestUniqueVariableName(name, lastStatement, true);
+    }
     PsiDeclarationStatement statement = myElementFactory.createVariableDeclarationStatement(name, type, myMethodCall);
     statement = (PsiDeclarationStatement)addToMethodCallLocation(statement);
     PsiVariable var = (PsiVariable)statement.getDeclaredElements()[0];
     myMethodCall = (PsiMethodCallExpression)var.getInitializer();
     var.getModifierList().replace(myOutputVariable.getModifierList());
+    return name;
   }
 
   private void adjustFinalParameters(final PsiMethod method) throws IncorrectOperationException {

java/java-tests/testData/refactoring/extractMethod/ExitPoints9_after.java

@@ -12,8 +12,8 @@ class Main {
     public static Result doIt(String name) {
         Result result;
 
-        Result result = newMethod(name);
-        if (result != null) return result;
+        Result result1 = newMethod(name);
+        if (result1 != null) return result1;
 
         result = new Result("Name is " + name);
         return result;

java/java-tests/testData/refactoring/extractMethod/NotNullCheckNameConflicts.java

@@ -0,0 +1,30 @@
+import org.jetbrains.annotations.NotNull;
+
+class X {
+    @NotNull
+    public X fun1(int x) {
+        return this;
+    }
+
+    public X fun2(boolean b) {
+
+        <selection>if (b) {
+            int x = 1;
+            return fun1(x);
+        }</selection>
+
+        int x = 0;
+        return null;
+    }
+
+
+
+
+    void foo(int i, int j) {
+        bar(i, j);
+    }
+
+    private void bar(int i, int j) {
+
+    }
+}

java/java-tests/testData/refactoring/extractMethod/NotNullCheckNameConflicts_after.java

@@ -0,0 +1,36 @@
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+class X {
+    @NotNull
+    public X fun1(int x) {
+        return this;
+    }
+
+    public X fun2(boolean b) {
+
+        X x1 = newMethod(b);
+        if (x1 != null) return x1;
+
+        int x = 0;
+        return null;
+    }
+
+    @Nullable
+    private X newMethod(boolean b) {
+        if (b) {
+            int x = 1;
+            return fun1(x);
+        }
+        return null;
+    }
+
+
+    void foo(int i, int j) {
+        bar(i, j);
+    }
+
+    private void bar(int i, int j) {
+
+    }
+}

java/java-tests/testSrc/com/intellij/refactoring/ExtractMethodTest.java

@@ -87,6 +87,10 @@ public class ExtractMethodTest extends LightCodeInsightTestCase {
     doTest();
   }
 
+  public void testNotNullCheckNameConflicts() throws Exception {
+    doTest();
+  }
+
   public void testContinueInside() throws Exception {
     doTest();
   }