[Mac] Support undo in the omnibox.

BUG=http://crbug.com/18084
TEST=You should be able to undo and redo typing and pasting in the omnibox, unless autocomplete has kicked in or you selected/highlighted an entry in the popup.
Review URL: http://codereview.chromium.org/246009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@31785 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 30 insertions, 0 deletions

diff --git a/chrome/browser/cocoa/autocomplete_text_field.h b/chrome/browser/cocoa/autocomplete_text_field.h
index 112212c..7c21527 100644
--- a/chrome/browser/cocoa/autocomplete_text_field.h
+++ b/chrome/browser/cocoa/autocomplete_text_field.h
@@ -8,6 +8,8 @@
 #import <Cocoa/Cocoa.h>
 #import "chrome/browser/cocoa/styled_text_field.h"
 
+#include "base/scoped_nsobject.h"
+
 @class AutocompleteTextFieldCell;
 
 // AutocompleteTextField intercepts UI actions for forwarding to
@@ -55,6 +57,10 @@ class AutocompleteTextFieldObserver {
 
 @interface AutocompleteTextField : StyledTextField {
  @private
+  // Undo manager for this text field.  We use a specific instance rather than
+  // the standard undo manager in order to let us clear the undo stack at will.
+  scoped_nsobject<NSUndoManager> undoManager_;
+
   AutocompleteTextFieldObserver* observer_;  // weak, owned by location bar.
 }
 
@@ -68,6 +74,9 @@ class AutocompleteTextFieldObserver {
 // contents if the control is already being edited.
 - (void)setAttributedStringValue:(NSAttributedString*)aString;
 
+// Clears the undo chain for this text field.
+- (void)clearUndoChain;
+
 @end
 
 #endif  // CHROME_BROWSER_COCOA_AUTOCOMPLETE_TEXT_FIELD_H_
diff --git a/chrome/browser/cocoa/autocomplete_text_field.mm b/chrome/browser/cocoa/autocomplete_text_field.mm
index c89fd17..1fb8aa5 100644
--- a/chrome/browser/cocoa/autocomplete_text_field.mm
+++ b/chrome/browser/cocoa/autocomplete_text_field.mm
@@ -160,4 +160,14 @@
   }
 }
 
+- (NSUndoManager*)undoManagerForTextView:(NSTextView*)textView {
+  if (!undoManager_.get())
+    undoManager_.reset([[NSUndoManager alloc] init]);
+  return undoManager_.get();
+}
+
+- (void)clearUndoChain {
+  [undoManager_ removeAllActions];
+}
+
 @end
diff --git a/chrome/browser/cocoa/autocomplete_text_field_unittest.mm b/chrome/browser/cocoa/autocomplete_text_field_unittest.mm
index 7dd65f6..66574ee 100644
--- a/chrome/browser/cocoa/autocomplete_text_field_unittest.mm
+++ b/chrome/browser/cocoa/autocomplete_text_field_unittest.mm
@@ -671,6 +671,17 @@ TEST_F(AutocompleteTextFieldTest, SetAttributedStringUndo) {
   EXPECT_TRUE([undoManager canUndo]);
   [field_ setAttributedStringValue:attributedString];
   EXPECT_TRUE([undoManager canUndo]);
+
+  // Verify that calling -clearUndoChain clears the undo chain.
+  [field_ clearUndoChain];
+  EXPECT_FALSE([undoManager canUndo]);
 }
 
+TEST_F(AutocompleteTextFieldTest, EditorGetsCorrectUndoManager) {
+  cocoa_helper_.makeFirstResponder(field_);
+
+  NSTextView* editor = static_cast<NSTextView*>([field_ currentEditor]);
+  EXPECT_TRUE(editor);
+  EXPECT_EQ([field_ undoManagerForTextView:editor], [editor undoManager]);
+}
 }  // namespace