Tracing for NSMenu timelines

ui/base/cocoa/menu_controller_unittest.mm

Index: ui/base/cocoa/menu_controller_unittest.mm
diff --git a/ui/base/cocoa/menu_controller_unittest.mm b/ui/base/cocoa/menu_controller_unittest.mm
index 24a86f021b341f6816283678508297e890195687..fabeff573eb68e03014331ac643e7e0272554be5 100644
--- a/ui/base/cocoa/menu_controller_unittest.mm
+++ b/ui/base/cocoa/menu_controller_unittest.mm
@@ -4,6 +4,7 @@
 
 #import <Cocoa/Cocoa.h>
 
+#include "base/mac/mac_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/strings/sys_string_conversions.h"
@@ -20,6 +21,35 @@
 
 using base::ASCIIToUTF16;
 
+@interface TestResponsiveMenuController : MenuController
+@property(assign, nonatomic) BOOL processEarly;
+@property(assign, nonatomic) BOOL sawItemEarly;
+@end
+
+@implementation TestResponsiveMenuController {
+  BOOL sawItemEarly_;
+  BOOL processEarly_;
+}
+
+@synthesize sawItemEarly = sawItemEarly_;
+@synthesize processEarly = processEarly_;
+
+- (BOOL)processItemSelectedEarly:(id)sender {
+  sawItemEarly_ = YES;
+  if (!processEarly_)
+    return NO;
+
+  [self itemSelected:sender];
+  return YES;
+}
+
+@end
+
+@interface NSMenuItem (Private)
+// Exposed to simulate in testing.
+- (void)_sendItemSelectedNote;
+@end
+
 namespace ui {
 
 namespace {
@@ -393,6 +423,81 @@ TEST_F(MenuControllerTest, OpenClose) {
   EXPECT_TRUE(delegate.did_close_);
 }
 
+// Verify that the private API used by MenuController's ResponsiveNSMenuItem
+// exists in the runtime. It's not a disaster if it disappears, (or AppKit
+// stops invoking it) but consumers will stop receiving opportunities to
+// -processItemSelectedEarly:.
+TEST_F(MenuControllerTest, SendItemSelectedNoteExists) {
+  // -_sendItemSelectedNote doesn't exist on 10.9 or 10.10. NSPopUpButton menus
+  // on 10.9 don't animate out, and always suffer from the brief "flash" of the
+  // old selection when the menu disappears.
+  // TODO(tapted): Find a hook on 10.10 if we deem it necessary.
+  if (base::mac::IsAtMostOS10_10())
+    return;
+
+  EXPECT_TRUE(
+      [NSMenuItem instancesRespondToSelector:@selector(_sendItemSelectedNote)]);
+}
+
+// Emulate the flow for -[MenuController processItemSelectedEarly:].
+TEST_F(MenuControllerTest, EmulateItemSelectedEarly) {
+  if (![NSMenuItem instancesRespondToSelector:@selector(_sendItemSelectedNote)])
+    return;
+
+  base::MessageLoopForUI message_loop;
+
+  Delegate delegate;
+  SimpleMenuModel model(&delegate);
+  model.AddItem(1, ASCIIToUTF16("foo"));
+
+  base::scoped_nsobject<TestResponsiveMenuController> controller(
+      [[TestResponsiveMenuController alloc] initWithModel:&model
+                                   useWithPopUpButtonCell:NO]);
+  [controller setProcessEarly:YES];
+
+  NSMenuItem* item = [[controller menu] itemAtIndex:0];
+  EXPECT_TRUE(item);
+
+  [controller menuWillOpen:[controller menu]];
+
+  // Pretend the first item got clicked. AppKit sends _sendItemSelectedNote to
+  // the menu item, then performs its action.
+  EXPECT_FALSE([controller sawItemEarly]);
+  EXPECT_EQ(0, delegate.execute_count_);
+  [item _sendItemSelectedNote];
+
+  EXPECT_TRUE([controller sawItemEarly]);
+
+  // Item gets executed early.
+  EXPECT_EQ(1, delegate.execute_count_);
+
+  // Simulate dismissal. This happens before the action.
+  [controller menuDidClose:[controller menu]];
+
+  // Perform the action normally. Shouldn't get executed again.
+  [[item target] performSelector:[item action] withObject:item];
+  EXPECT_EQ(1, delegate.execute_count_);
+
+  // Repeat, without processing early.
+  [controller setProcessEarly:NO];
+  [controller setSawItemEarly:NO];
+  delegate.execute_count_ = 0;
+  delegate.did_show_ = delegate.did_close_ = false;
+
+  [controller menuWillOpen:[controller menu]];
+  [item _sendItemSelectedNote];
+
+  // Saw it, but didn't execute.
+  EXPECT_TRUE([controller sawItemEarly]);
+  EXPECT_EQ(0, delegate.execute_count_);
+
+  [controller menuDidClose:[controller menu]];
+
+  // Perform the action normally. Now executes.
+  [[item target] performSelector:[item action] withObject:item];
+  EXPECT_EQ(1, delegate.execute_count_);
+}
+
 }  // namespace
 
 }  // namespace ui