From 8f1514a2abcecc708028837bc898d7e311d7f0ff Mon Sep 17 00:00:00 2001
From: Dmitry Batrak <Dmitry.Batrak@jetbrains.com>
Date: Mon, 13 Oct 2014 19:12:36 +0400
Subject: [PATCH] IDEA-93998 In overwrite mode  it is impossible to add new
 line to the file

---
 .../intellij/openapi/actionSystem/IdeActions.java   |  1 +
 .../openapi/editor/actions/EnterAction.java         | 13 +++++++++----
 .../openapi/editor/actions/EditorActionTest.java    |  7 +++++++
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/platform/platform-api/src/com/intellij/openapi/actionSystem/IdeActions.java b/platform/platform-api/src/com/intellij/openapi/actionSystem/IdeActions.java
index 5043ba3792fb..66486d8da4be 100644
--- a/platform/platform-api/src/com/intellij/openapi/actionSystem/IdeActions.java
+++ b/platform/platform-api/src/com/intellij/openapi/actionSystem/IdeActions.java
@@ -56,6 +56,7 @@ public interface IdeActions {
   @NonNls String ACTION_EDITOR_CLONE_CARET_BELOW= "EditorCloneCaretBelow";
   @NonNls String ACTION_EDITOR_CLONE_CARET_ABOVE= "EditorCloneCaretAbove";
   @NonNls String ACTION_EDITOR_TOGGLE_STICKY_SELECTION= "EditorToggleStickySelection";
+  @NonNls String ACTION_EDITOR_TOGGLE_OVERWRITE_MODE= "EditorToggleInsertState";
 
   @NonNls String ACTION_EDITOR_NEXT_TEMPLATE_VARIABLE = "NextTemplateVariable";
   @NonNls String ACTION_EDITOR_PREVIOUS_TEMPLATE_VARIABLE = "PreviousTemplateVariable";
diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/actions/EnterAction.java b/platform/platform-impl/src/com/intellij/openapi/editor/actions/EnterAction.java
index ea2107632122..5669f5c19950 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/actions/EnterAction.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/actions/EnterAction.java
@@ -58,9 +58,15 @@ public class EnterAction extends EditorAction {
 
   public static void insertNewLineAtCaret(Editor editor) {
     MacUIUtil.hideCursor();
+    Document document = editor.getDocument();
+    int caretLine = editor.getCaretModel().getLogicalPosition().line;
     if(!editor.isInsertMode()) {
-      if(editor.getCaretModel().getLogicalPosition().line < editor.getDocument().getLineCount()-1) {
-        LogicalPosition pos = new LogicalPosition(editor.getCaretModel().getLogicalPosition().line+1, 0);
+      int lineCount = document.getLineCount();
+      if(caretLine < lineCount) {
+        if (caretLine == lineCount - 1) {
+          document.insertString(document.getTextLength(), "\n");
+        }
+        LogicalPosition pos = new LogicalPosition(caretLine + 1, 0);
         editor.getCaretModel().moveToLogicalPosition(pos);
         editor.getSelectionModel().removeSelection();
         editor.getScrollingModel().scrollToCaret(ScrollType.RELATIVE);
@@ -69,10 +75,9 @@ public class EnterAction extends EditorAction {
     }
     EditorModificationUtil.deleteSelectedText(editor);
     // Smart indenting here:
-    Document document = editor.getDocument();
     CharSequence text = document.getCharsSequence();
 
-    int indentLineNum = editor.getCaretModel().getLogicalPosition().line;
+    int indentLineNum = caretLine;
     int lineLength = 0;
     if (document.getLineCount() > 0) {
       for(;indentLineNum >= 0; indentLineNum--) {
diff --git a/platform/platform-tests/testSrc/com/intellij/openapi/editor/actions/EditorActionTest.java b/platform/platform-tests/testSrc/com/intellij/openapi/editor/actions/EditorActionTest.java
index b3dee9baedb5..a23766200251 100644
--- a/platform/platform-tests/testSrc/com/intellij/openapi/editor/actions/EditorActionTest.java
+++ b/platform/platform-tests/testSrc/com/intellij/openapi/editor/actions/EditorActionTest.java
@@ -138,4 +138,11 @@ public class EditorActionTest extends AbstractEditorTest {
     executeAction(IdeActions.ACTION_EDITOR_MOVE_CARET_RIGHT);
     assertEquals(new VisualPosition(0, 6), myEditor.getCaretModel().getVisualPosition());
   }
+
+  public void testEnterOnLastLineInOverwriteMode() throws Exception {
+    init("text<caret>", TestFileType.TEXT);
+    executeAction(IdeActions.ACTION_EDITOR_TOGGLE_OVERWRITE_MODE);
+    executeAction(IdeActions.ACTION_EDITOR_ENTER);
+    checkResultByText("text\n<caret>");
+  }
 }
\ No newline at end of file