error nodes support

platform/platform-api/src/com/intellij/ide/diff/DiffElement.java

@@ -44,6 +44,7 @@ import java.util.concurrent.Callable;
  */
 public abstract class DiffElement<T> implements Disposable {
   public static final DiffElement[] EMPTY_ARRAY = new DiffElement[0];
+  public static final DiffElement ERROR_NODE = new DiffErrorElement("Can't load elements", "An error has been occurred while getting children");
   private DiffPanel myDiffPanel;
   private Editor myEditor;
   private static final Logger LOG = Logger.getInstance(DiffElement.class.getName());

platform/platform-api/src/com/intellij/ide/diff/DiffErrorElement.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2000-2011 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.ide.diff;
+
+import com.intellij.openapi.project.Project;
+import com.intellij.util.ArrayUtil;
+import com.intellij.util.Icons;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.io.IOException;
+
+/**
+ * @author Konstantin Bulenkov
+ */
+public class DiffErrorElement extends DiffElement {
+  private final String myMessage;
+  private final JTextArea myDescription;
+
+  public DiffErrorElement() {
+    this("Can't load children", "");
+  }
+
+  public DiffErrorElement(@NotNull String message, @NotNull String description) {
+    myMessage = message;
+    myDescription = new JTextArea(description);
+    //myDescription.setBackground(new Color(0,0,0,0));
+    myDescription.setEditable(false);
+  }
+
+
+
+  @Override
+  public String getPath() {
+    return "";
+  }
+
+  @NotNull
+  @Override
+  public String getName() {
+    return myMessage;
+  }
+
+  @Override
+  public long getSize() {
+    return -1;
+  }
+
+  @Override
+  public long getTimeStamp() {
+    return -1;
+  }
+
+  @Override
+  public boolean isContainer() {
+    return false;
+  }
+
+  @Override
+  public DiffElement[] getChildren() throws IOException {
+    return EMPTY_ARRAY;
+  }
+
+  @Override
+  public byte[] getContent() throws IOException {
+    return ArrayUtil.EMPTY_BYTE_ARRAY;
+  }
+
+  @Override
+  public Object getValue() {
+    return null;
+  }
+
+  @Override
+  public Icon getIcon() {
+    return Icons.ERROR_INTRODUCTION_ICON;
+  }
+
+  @Override
+  public JComponent getViewComponent(Project project, @Nullable DiffElement target) {
+    return myDescription;
+  }
+}

platform/vcs-impl/src/com/intellij/openapi/diff/impl/dir/DTree.java

@@ -16,6 +16,7 @@
 package com.intellij.openapi.diff.impl.dir;
 
 import com.intellij.ide.diff.DiffElement;
+import com.intellij.ide.diff.DiffErrorElement;
 import com.intellij.ide.diff.DirDiffSettings;
 import com.intellij.util.containers.HashMap;
 import com.intellij.util.containers.SortedList;
@@ -27,6 +28,8 @@ import java.util.Arrays;
 import java.util.Collection;
 import java.util.Comparator;
 
+import static com.intellij.openapi.diff.impl.dir.DType.ERROR;
+
 /**
  * @author Konstantin Bulenkov
  */
@@ -143,7 +146,9 @@ public class DTree {
     for (DTree tree : getChildren()) {
       final DiffElement<?> src = tree.getSource();
       final DiffElement<?> trg = tree.getTarget();
-      if (src == null && trg != null) {
+      if (src instanceof DiffErrorElement || trg instanceof DiffErrorElement) {
+        tree.setType(ERROR);
+      } else if (src == null && trg != null) {
         tree.setType(DType.TARGET);
       } else if (src != null && trg == null) {
         tree.setType(DType.SOURCE);
@@ -172,6 +177,10 @@ public class DTree {
 
   public void updateVisibility(DirDiffSettings settings) {
     if (children.isEmpty()) {
+     if (type == ERROR) {
+        myVisible = true;
+       return;
+      }
       if (type != DType.SEPARATOR && !"".equals(settings.getFilter())) {
         if (!settings.getFilterPattern().matcher(getName()).matches()) {
           myVisible = false;
@@ -189,6 +198,7 @@ public class DTree {
           myVisible = settings.showNewOnTarget;
           break;
         case SEPARATOR:
+        case ERROR:
           myVisible = true;
           break;
         case CHANGED:

platform/vcs-impl/src/com/intellij/openapi/diff/impl/dir/DType.java

@@ -18,4 +18,4 @@ package com.intellij.openapi.diff.impl.dir;
 /**
 * @author Konstantin Bulenkov
 */
-public enum DType {SOURCE, TARGET, SEPARATOR, CHANGED, EQUAL}
+public enum DType {SOURCE, TARGET, SEPARATOR, CHANGED, EQUAL, ERROR}

platform/vcs-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffElement.java

@@ -22,7 +22,7 @@ import org.jetbrains.annotations.Nullable;
 
 import javax.swing.*;
 
-import static com.intellij.openapi.diff.impl.dir.DirDiffOperation.*;
+import static com.intellij.openapi.diff.impl.dir.DirDiffOperation.COPY_TO;
 
 /**
  * @author Konstantin Bulenkov
@@ -43,7 +43,10 @@ public class DirDiffElement {
     myTarget = target;
     myTargetLength = target == null || target.isContainer() ? -1 : target.getSize();
     myName = name;
-    if (isSource()) {
+    if (type == DType.ERROR) {
+      myOperation = DirDiffOperation.NONE;
+    }
+    else if (isSource()) {
       myOperation = COPY_TO;
     }
     else if (isTarget()) {
@@ -67,13 +70,18 @@ public class DirDiffElement {
   }
 
   private static String getLastModification(DiffElement file) {
-    return DateFormatUtil.formatDateTime(file.getTimeStamp());
+    final long timeStamp = file.getTimeStamp();
+    return timeStamp < 0 ? "" : DateFormatUtil.formatDateTime(timeStamp);
   }
 
   public static DirDiffElement createChange(@NotNull DiffElement source, @NotNull DiffElement target) {
     return new DirDiffElement(source, target, DType.CHANGED, source.getName());
   }
 
+  public static DirDiffElement createError(@Nullable DiffElement source, @Nullable DiffElement target) {
+    return new DirDiffElement(source, target, DType.ERROR, source == null ? target.getName() : source.getName());
+  }
+
   public static DirDiffElement createSourceOnly(@NotNull DiffElement source) {
     return new DirDiffElement(source, null, DType.SOURCE, null);
   }
@@ -109,7 +117,7 @@ public class DirDiffElement {
   @Nullable
   public String getSourceName() {
     return myType == DType.CHANGED || myType == DType.SOURCE || myType == DType.EQUAL
-           ? mySource.getName() : null;
+           ? mySource.getName() : mySource == null ? null : mySource.getName();
   }
 
   @Nullable
@@ -120,7 +128,7 @@ public class DirDiffElement {
   @Nullable
   public String getTargetName() {
     return myType == DType.CHANGED || myType == DType.TARGET || myType == DType.EQUAL
-           ? myTarget.getName() : null;
+           ? myTarget.getName() : myTarget == null ? null : myTarget.getName();
   }
 
   @Nullable

platform/vcs-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffOperation.java

@@ -26,7 +26,7 @@ import java.awt.*;
  * @author Konstantin Bulenkov
  */
 public enum DirDiffOperation {
-  COPY_TO, COPY_FROM, MERGE, EQUAL;
+  COPY_TO, COPY_FROM, MERGE, EQUAL, NONE;
 
   public Icon getIcon() {
     switch (this) {
@@ -34,6 +34,7 @@ public enum DirDiffOperation {
       case COPY_FROM: return IconLoader.getIcon("/vcs/arrow_left.png");
       case MERGE:     return IconLoader.getIcon("/vcs/not_equal.png");
       case EQUAL:     return IconLoader.getIcon("/vcs/equal.png");
+      case NONE:
     }
     return EmptyIcon.create(16);
   }
@@ -46,6 +47,7 @@ public enum DirDiffOperation {
       case MERGE:
         return FileStatus.COLOR_MODIFIED;
       case EQUAL:
+      case NONE:
     }
     return Color.BLACK;
   }

platform/vcs-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffPanel.java

@@ -113,14 +113,20 @@ public class DirDiffPanel implements Disposable {
             }
 
           } else {
-            final DiffElement object = element.isSource() ? element.getSource() : element.getTarget();
+            final DiffElement object;
+            if (element.getType() == DType.ERROR) {
+              object = element.getSource() == null ? element.getTarget() : element.getSource();
+            } else {
+              object = element.isSource() ? element.getSource() : element.getTarget();
+            }
             myViewComponent = object.getViewComponent(project, null);
 
             if (myViewComponent != null) {
               myCurrentElement = object;
               myDiffPanel.add(myViewComponent, BorderLayout.CENTER);
               DataManager.registerDataProvider(myDiffPanel, myCurrentElement.getDataProvider(project));
-              myViewComponent.revalidate();
+              myDiffPanel.revalidate();
+              myDiffPanel.repaint();
             } else {
               myDiffPanel.add(getErrorLabel(), BorderLayout.CENTER);
               myDiffPanel.revalidate();

platform/vcs-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffTableModel.java

@@ -246,6 +246,8 @@ public class DirDiffTableModel extends AbstractTableModel implements Disposable
             case EQUAL:
               elements.add(DirDiffElement.createEqual(child.getSource(), child.getTarget()));
               break;
+            case ERROR:
+              elements.add(DirDiffElement.createError(child.getSource(), child.getTarget()));
           }
         }
       } else {