IDEA-48401 Ctrl+D should place caret on the variable name when copying a line consisting of variable declaration

java/java-tests/testSrc/com/intellij/codeInsight/DuplicateActionTest.groovy

@@ -0,0 +1,38 @@
+package com.intellij.codeInsight;
+
+
+import com.intellij.openapi.actionSystem.IdeActions
+import com.intellij.testFramework.fixtures.LightCodeInsightFixtureTestCase
+import org.jetbrains.annotations.NonNls
+
+public class DuplicateActionTest extends LightCodeInsightFixtureTestCase {
+  public void testOneLine() {
+    doTest '''xxx<caret>
+''', "txt", '''xxx
+xxx<caret>
+'''
+  }
+
+  public void testEmpty() {
+    doTest '<caret>', "txt", '\n<caret>'
+  }
+
+  private void doTest(String before, @NonNls String ext, String after) {
+    myFixture.configureByText("a." + ext, before);
+    myFixture.performEditorAction(IdeActions.ACTION_EDITOR_DUPLICATE)
+    myFixture.checkResult(after);
+  }
+
+  public void testSelectName() {
+    doTest '''
+class C {
+  void foo() {}<caret>
+}
+''', 'java', '''
+class C {
+  void foo() {}
+  void <caret>foo() {}
+}
+'''
+  }
+}

platform/lang-impl/src/com/intellij/openapi/editor/actions/NamedElementDuplicateHandler.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2000-2012 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.openapi.editor.actions;
+
+import com.intellij.openapi.actionSystem.DataContext;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.editor.LogicalPosition;
+import com.intellij.openapi.editor.VisualPosition;
+import com.intellij.openapi.editor.actionSystem.EditorActionHandler;
+import com.intellij.openapi.editor.actionSystem.EditorWriteActionHandler;
+import com.intellij.openapi.editor.ex.util.EditorUtil;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.Pair;
+import com.intellij.openapi.util.TextRange;
+import com.intellij.psi.*;
+import com.intellij.util.text.CharArrayUtil;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * @author peter
+ */
+public class NamedElementDuplicateHandler extends EditorWriteActionHandler {
+  private final EditorActionHandler myOriginal;
+
+  public NamedElementDuplicateHandler(EditorActionHandler original) {
+    myOriginal = original;
+  }
+
+  @Override
+  public void executeWriteAction(Editor editor, DataContext dataContext) {
+    Project project = editor.getProject();
+    if (project != null && !editor.getSelectionModel().hasSelection()) {
+      PsiDocumentManager.getInstance(project).commitDocument(editor.getDocument());
+      PsiFile file = PsiDocumentManager.getInstance(project).getPsiFile(editor.getDocument());
+      if (file != null) {
+        VisualPosition caret = editor.getCaretModel().getVisualPosition();
+        Pair<LogicalPosition, LogicalPosition> lines = EditorUtil.calcCaretLinesRange(editor, caret, caret);
+        TextRange toDuplicate = new TextRange(editor.logicalPositionToOffset(lines.first), editor.logicalPositionToOffset(lines.second));
+
+        PsiNamedElement named = findNamedElement(editor, file, toDuplicate);
+        if (named != null) {
+          editor.getCaretModel().moveToOffset(named.getTextOffset());
+        }
+      }
+    }
+
+    myOriginal.execute(editor, dataContext);
+  }
+
+  @Nullable
+  private static PsiNamedElement findNamedElement(Editor editor, PsiFile file, TextRange toDuplicate) {
+    int nonWs = CharArrayUtil.shiftForward(editor.getDocument().getCharsSequence(), toDuplicate.getStartOffset(), "\n\t ");
+    PsiElement psi = file.findElementAt(nonWs);
+    PsiNamedElement named = null;
+    while (psi != null) {
+      TextRange range = psi.getTextRange();
+      if (range == null || psi instanceof PsiFile || !toDuplicate.contains(psi.getTextRange())) {
+        break;
+      }
+      if (psi instanceof PsiNamedElement) {
+        named = (PsiNamedElement)psi;
+      }
+      psi = psi.getParent();
+    }
+    return named;
+  }
+}

platform/platform-resources/src/META-INF/LangExtensions.xml

@@ -566,6 +566,8 @@
                        implementationClass="com.intellij.codeInsight.editorActions.BackspaceToWordStartHandler"/>
   <editorTypedHandler implementationClass="com.intellij.codeInsight.editorActions.TypedHandler"/>
 
+  <editorActionHandler action="EditorDuplicate" implementationClass="com.intellij.openapi.editor.actions.NamedElementDuplicateHandler"/>
+
   <!-- LookupManagerActions -->
   <editorActionHandler action="EditorUp" implementationClass="com.intellij.codeInsight.lookup.impl.LookupActionHandler$UpHandler"/>
   <editorActionHandler action="EditorDown" implementationClass="com.intellij.codeInsight.lookup.impl.LookupActionHandler$DownHandler"/>