MacViews: Merge single-character edits, map (and validate) undo and redo

Undo and redo are mapped in a similar way to cut/copy/paste on Mac, via
the mainMenu's performKeyEquivalent, and the Cocoa responder chain.

This CL adds responders for undo: and redo:

Single-character editing commands were not being merged into a single
edit. For example, typing {'c', 'a', 't', Cmd+Z} would only undo the 't'
not the entire 'cat'. This CL fixes by detecting single-character
inserts in response to a keyDown event.

Then, for "redo", some of the textfield unittests would send both Ctrl+Y
and Ctrl+Shift+Z. Cmd+Y for undo isn't supported on Mac (it's mapped to
History -> Show Full History). So a wrapper is added that just sends
Cmd+Shfit+Z again.

Gets the following tests passing:
     TextfieldTest.DragAndDrop_ToTheLeft
     TextfieldTest.DragAndDrop_ToTheRight
     TextfieldTest.UndoRedoTest

BUG=454353

Review URL: https://codereview.chromium.org/923903002

Cr-Commit-Position: refs/heads/master@{#316992}

ui/views/cocoa/bridged_content_view.h

@@ -32,6 +32,9 @@ class View;
 
   // A tracking area installed to enable mouseMoved events.
   ui::ScopedCrTrackingArea trackingArea_;
+
+  // Whether the view is reacting to a keyDown event on the view.
+  BOOL inKeyDown_;
 }
 
 @property(readonly, nonatomic) views::View* hostedView;

ui/views/cocoa/bridged_content_view.mm

@@ -67,6 +67,8 @@ gfx::Point MovePointToWindow(const NSPoint& point,
           eventFlags:(int)eventFlags;
 
 // Menu action handlers.
+- (void)undo:(id)sender;
+- (void)redo:(id)sender;
 - (void)cut:(id)sender;
 - (void)copy:(id)sender;
 - (void)paste:(id)sender;
@@ -165,6 +167,27 @@ gfx::Point MovePointToWindow(const NSPoint& point,
   hostedView_->GetWidget()->GetInputMethod()->DispatchKeyEvent(event);
 }
 
+- (void)undo:(id)sender {
+  // This DCHECK is more strict than a similar check in handleAction:. It can be
+  // done here because the actors sending these actions should be calling
+  // validateUserInterfaceItem: before enabling UI that allows these messages to
+  // be sent. Checking it here would be too late to provide correct UI feedback
+  // (e.g. there will be no "beep").
+  DCHECK(textInputClient_->IsEditCommandEnabled(IDS_APP_UNDO));
+  [self handleAction:IDS_APP_UNDO
+             keyCode:ui::VKEY_Z
+             domCode:ui::DomCode::KEY_Z
+          eventFlags:ui::EF_CONTROL_DOWN];
+}
+
+- (void)redo:(id)sender {
+  DCHECK(textInputClient_->IsEditCommandEnabled(IDS_APP_REDO));
+  [self handleAction:IDS_APP_REDO
+             keyCode:ui::VKEY_Z
+             domCode:ui::DomCode::KEY_Z
+          eventFlags:ui::EF_CONTROL_DOWN | ui::EF_SHIFT_DOWN];
+}
+
 - (void)cut:(id)sender {
   DCHECK(textInputClient_->IsEditCommandEnabled(IDS_APP_CUT));
   [self handleAction:IDS_APP_CUT
@@ -243,7 +266,9 @@ gfx::Point MovePointToWindow(const NSPoint& point,
 
 - (void)keyDown:(NSEvent*)theEvent {
   // Convert the event into an action message, according to OSX key mappings.
+  inKeyDown_ = YES;
   [self interpretKeyEvents:@[ theEvent ]];
+  inKeyDown_ = NO;
 }
 
 - (void)mouseDown:(NSEvent*)theEvent {
@@ -568,7 +593,17 @@ gfx::Point MovePointToWindow(const NSPoint& point,
     return;
 
   textInputClient_->DeleteRange(gfx::Range(replacementRange));
-  textInputClient_->InsertText(base::SysNSStringToUTF16(text));
+
+  // If a single character is inserted by keyDown's call to interpretKeyEvents:
+  // then use InsertChar() to allow editing events to be merged. The second
+  // argument is the key modifier, which interpretKeyEvents: will have already
+  // processed, so don't send it to InsertChar() as well. E.g. Alt+S puts 'ß' in
+  // |text| but sending 'Alt' to InsertChar would filter it out since it thinks
+  // it's a command. Actual commands (e.g. Cmd+S) won't go through insertText:.
+  if (inKeyDown_ && [text length] == 1)
+    textInputClient_->InsertChar([text characterAtIndex:0], 0);
+  else
+    textInputClient_->InsertText(base::SysNSStringToUTF16(text));
 }
 
 - (NSRange)markedRange {
@@ -620,6 +655,10 @@ gfx::Point MovePointToWindow(const NSPoint& point,
 
   SEL action = [item action];
 
+  if (action == @selector(undo:))
+    return textInputClient_->IsEditCommandEnabled(IDS_APP_UNDO);
+  if (action == @selector(redo:))
+    return textInputClient_->IsEditCommandEnabled(IDS_APP_REDO);
   if (action == @selector(cut:))
     return textInputClient_->IsEditCommandEnabled(IDS_APP_CUT);
   if (action == @selector(copy:))

ui/views/controls/textfield/textfield_unittest.cc

@@ -1087,11 +1087,11 @@ TEST_F(TextfieldTest, DragAndDrop_ToTheRight) {
   EXPECT_STR_EQ("", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("hello world", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("h welloorld", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("h welloorld", textfield_->text());
 }
 
@@ -1141,11 +1141,11 @@ TEST_F(TextfieldTest, DragAndDrop_ToTheLeft) {
   EXPECT_STR_EQ("", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("hello world", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("h worlellod", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("h worlellod", textfield_->text());
 }
 
@@ -1364,9 +1364,9 @@ TEST_F(TextfieldTest, UndoRedoTest) {
   EXPECT_STR_EQ("", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("a", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("a", textfield_->text());
 
   // AppendText
@@ -1375,7 +1375,7 @@ TEST_F(TextfieldTest, UndoRedoTest) {
   EXPECT_STR_EQ("ab", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("a", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("ab", textfield_->text());
 
   // SetText
@@ -1387,9 +1387,9 @@ TEST_F(TextfieldTest, UndoRedoTest) {
   EXPECT_STR_EQ("abc", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("ab", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("abc", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("abc", textfield_->text());
   textfield_->SetText(ASCIIToUTF16("123"));
   textfield_->SetText(ASCIIToUTF16("123"));
@@ -1406,11 +1406,11 @@ TEST_F(TextfieldTest, UndoRedoTest) {
   EXPECT_STR_EQ("ab", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("a", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("ab", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("123", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("1234", textfield_->text());
 
   // Undoing to the same text shouldn't call ContentsChanged.
@@ -1422,13 +1422,13 @@ TEST_F(TextfieldTest, UndoRedoTest) {
   EXPECT_STR_EQ("abc", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("1234", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("abc", textfield_->text());
 
   // Delete/Backspace
   SendKeyEvent(ui::VKEY_BACK);
   EXPECT_STR_EQ("ab", textfield_->text());
-  SendKeyEvent(ui::VKEY_HOME);
+  SendHomeEvent(false);
   SendKeyEvent(ui::VKEY_DELETE);
   EXPECT_STR_EQ("b", textfield_->text());
   SendKeyEvent(ui::VKEY_A, false, true);
@@ -1440,16 +1440,38 @@ TEST_F(TextfieldTest, UndoRedoTest) {
   EXPECT_STR_EQ("ab", textfield_->text());
   SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("abc", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("ab", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
   EXPECT_STR_EQ("b", textfield_->text());
-  SendKeyEvent(ui::VKEY_Y, false, true);
+  SendKeyEvent(ui::VKEY_Z, true, true);
+  EXPECT_STR_EQ("", textfield_->text());
+  SendKeyEvent(ui::VKEY_Z, true, true);
+  EXPECT_STR_EQ("", textfield_->text());
+}
+
+// Most platforms support Ctrl+Y as an alternative to Ctrl+Shift+Z, but on Mac
+// that is bound to "Show full history", so is not mapped as an editing
+// command. So, on Mac, send Cmd+Shift+Z.
+#if !defined(OS_MACOSX)
+
+// Test that Ctrl+Y works for Redo, as well as Ctrl+Shift+Z.
+TEST_F(TextfieldTest, RedoWithCtrlY) {
+  InitTextfield();
+  SendKeyEvent(ui::VKEY_A);
+  EXPECT_STR_EQ("a", textfield_->text());
+  SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("", textfield_->text());
   SendKeyEvent(ui::VKEY_Y, false, true);
+  EXPECT_STR_EQ("a", textfield_->text());
+  SendKeyEvent(ui::VKEY_Z, false, true);
   EXPECT_STR_EQ("", textfield_->text());
+  SendKeyEvent(ui::VKEY_Z, true, true);
+  EXPECT_STR_EQ("a", textfield_->text());
 }
 
+#endif  // !defined(OS_MACOSX)
+
 TEST_F(TextfieldTest, CutCopyPaste) {
   InitTextfield();