[MacViews] Enable dragging a window by its caption/draggable areas.

ui/views/cocoa/bridged_native_widget_interactive_uitest.mm

Index: ui/views/cocoa/bridged_native_widget_interactive_uitest.mm
diff --git a/ui/views/cocoa/bridged_native_widget_interactive_uitest.mm b/ui/views/cocoa/bridged_native_widget_interactive_uitest.mm
index b0962fb9a27116e7ee142f1f5933445a873b23ff..aabc8c0cbf5bd919ddafe38cf1c8ac9317e95bcc 100644
--- a/ui/views/cocoa/bridged_native_widget_interactive_uitest.mm
+++ b/ui/views/cocoa/bridged_native_widget_interactive_uitest.mm
@@ -9,7 +9,51 @@
 #import "base/mac/mac_util.h"
 #import "base/mac/sdk_forward_declarations.h"
 #import "ui/base/test/nswindow_fullscreen_notification_waiter.h"
+#include "ui/base/hit_test.h"
+#include "ui/events/test/cocoa_test_event_utils.h"
 #include "ui/views/test/widget_test.h"
+#include "ui/views/window/native_frame_view.h"
+
+// Watches for NSNotifications from the default notification center.
+@interface WindowedNSNotificationObserver : NSObject {

[jackhou1, 2015/06/02 06:33:09]

This can probably be merged with the one in app_shim_interactive_uitest_mac.mm.
That one uses the shared workspace instead of the default notification center,
so there would need to be some logic to distinguish them. WDYT? Is there a good
place for this?

[tapted, 2015/06/03 00:28:37]

are they both called WindowedNSNotificationObserver .. (shouldn't there be a
symbol conflict if they are both linked into interactive_ui_tests ?)

but! there's also one in bridged_native_widget_interactive_uitest already, so we
should definitely merge them all.

There's also NSWindowFullscreenNotificationWaiter in ui/base/test but it's
slightly different. Not sure if there's a neat way to merge that as well, but
these other 3 should be merged into something going into the same folder.

[jackhou1, 2015/06/03 04:04:44]

Nope, this one is in macviews_interactive_ui_tests.
That's this file, did you mean somewhere else?
 
Done.

[tapted, 2015/06/03 07:04:48]

oh whoops - nope. #wirescrossed

+ @private
+  BOOL notificationReceived_;
+  scoped_ptr<base::RunLoop> runLoop_;
+}
+
+- (id)initForNotification:(NSString*)name;
+- (void)observe:(NSNotification*)notification;
+- (void)wait;
+@end
+
+@implementation WindowedNSNotificationObserver
+
+- (id)initForNotification:(NSString*)name {
+  if (self = [super init]) {
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(observe:)
+                                                 name:name
+                                               object:nil];
+  }
+  return self;
+}
+
+- (void)observe:(NSNotification*)notification {
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  notificationReceived_ = YES;
+  if (runLoop_.get())
+    runLoop_->Quit();
+}
+
+- (void)wait {
+  if (notificationReceived_)
+    return;
+
+  runLoop_.reset(new base::RunLoop);
+  runLoop_->Run();
+}
+
+@end
 
 namespace views {

[tapted, 2015/06/03 00:28:37]

add namespace test { after this (i.e. whole file should be views::test:: rather
than just views::

[jackhou1, 2015/06/03 04:04:44]

Done.

 
@@ -144,4 +188,144 @@ TEST_F(BridgedNativeWidgetUITest, FullscreenEnterAndExit) {
   EXPECT_EQ(restored_bounds, widget_->GetRestoredBounds());
 }
 
+namespace {
+
+// This is used to wait for reposted events to be seen. We can't just use
+// RunPendingMessages() because CGEventPost might not be synchronous.
+class HitTestBridgedNativeWidget : public BridgedNativeWidget {
+ public:
+  HitTestBridgedNativeWidget(NativeWidgetMac* widget)
+      : BridgedNativeWidget(widget) {}
+
+  bool ShouldRepostPendingLeftMouseDown(NSPoint location_in_window) override {
+    bool draggable_before = [ns_view() mouseDownCanMoveWindow];
+    bool should_repost = BridgedNativeWidget::ShouldRepostPendingLeftMouseDown(
+        location_in_window);
+    bool draggable_after = [ns_view() mouseDownCanMoveWindow];
+
+    if (run_loop_.get() && draggable_before && !draggable_after)
+      run_loop_->Quit();
+
+    return should_repost;
+  }
+
+  void WaitForRepost() {
+    run_loop_.reset(new base::RunLoop);
+    run_loop_->Run();
+  }
+
+ private:
+  scoped_ptr<base::RunLoop> run_loop_;
+};
+
+// This is used to return a customized result to NonClientHitTest.
+class HitTestNonClientFrameView : public NativeFrameView {
+ public:
+  HitTestNonClientFrameView(Widget* widget)
+      : NativeFrameView(widget), hit_test_result_(HTNOWHERE) {}
+
+  // NonClientFrameView overrides:
+  int NonClientHitTest(const gfx::Point& point) override {
+    return hit_test_result_;
+  }
+
+  void set_hit_test_result(int component) { hit_test_result_ = component; }
+
+ private:
+  int hit_test_result_;
+};
+
+}  // namespace
+
+// This is used to inject test versions of NativeFrameView and
+// BridgedNativeWidget.
+// Outside anonymous namespace so NativeWidgetMac can friend this.
+class HitTestNativeWidgetMac : public NativeWidgetMac {
+ public:
+  HitTestNativeWidgetMac(internal::NativeWidgetDelegate* delegate,
+                         NativeFrameView* native_frame_view)
+      : NativeWidgetMac(delegate), native_frame_view_(native_frame_view) {
+    NativeWidgetMac::bridge_.reset(new HitTestBridgedNativeWidget(this));
+  }
+
+  HitTestBridgedNativeWidget* bridge() {
+    return static_cast<HitTestBridgedNativeWidget*>(
+        NativeWidgetMac::bridge_.get());
+  }
+
+  // internal::NativeWidgetPrivate:
+  NonClientFrameView* CreateNonClientFrameView() override {
+    return native_frame_view_;
+  }
+
+ private:
+  // Owned by Widget.
+  NativeFrameView* native_frame_view_;
+};
+
+TEST_F(BridgedNativeWidgetUITest, HitTest) {
+  Widget widget;
+  HitTestNonClientFrameView* frame_view =
+      new HitTestNonClientFrameView(&widget);
+  HitTestNativeWidgetMac* native_widget =
+      new HitTestNativeWidgetMac(&widget, frame_view);
+  Widget::InitParams init_params =
+      CreateParams(Widget::InitParams::TYPE_WINDOW);
+  init_params.native_widget = native_widget;
+  init_params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
+  init_params.bounds = gfx::Rect(100, 100, 400, 300);
+  widget.Init(init_params);
+  widget.Show();
+  RunPendingMessages();
+
+  frame_view->set_hit_test_result(HTCAPTION);
+  {
+    EXPECT_EQ(100, [widget.GetNativeWindow() frame].origin.x);
+
+    NSEvent* mouse_down = cocoa_test_event_utils::LeftMouseDownAtPointInWindow(
+        NSMakePoint(10, 10), widget.GetNativeWindow());
+    CGEventPost(kCGSessionEventTap, [mouse_down CGEvent]);
+    native_widget->bridge()->WaitForRepost();
+
+    base::scoped_nsobject<WindowedNSNotificationObserver> ns_observer(
+        [[WindowedNSNotificationObserver alloc]
+            initForNotification:NSWindowDidMoveNotification]);
+    NSEvent* mouse_drag = cocoa_test_event_utils::MouseEventAtPointInWindow(
+        NSMakePoint(110, 110), NSLeftMouseDragged, widget.GetNativeWindow(),
+        1u);
+    CGEventPost(kCGSessionEventTap, [mouse_drag CGEvent]);
+    [ns_observer wait];
+    EXPECT_EQ(200, [widget.GetNativeWindow() frame].origin.x);
+
+    NSEvent* mouse_up = cocoa_test_event_utils::MouseEventAtPointInWindow(
+        NSMakePoint(110, 110), NSLeftMouseUp, widget.GetNativeWindow(), 2u);
+    CGEventPost(kCGSessionEventTap, [mouse_up CGEvent]);
+    RunPendingMessages();
+    EXPECT_EQ(200, [widget.GetNativeWindow() frame].origin.x);
+  }
+
+  frame_view->set_hit_test_result(HTCLIENT);
+  {
+    EXPECT_EQ(200, [widget.GetNativeWindow() frame].origin.x);
+
+    NSEvent* mouse_down = cocoa_test_event_utils::LeftMouseDownAtPointInWindow(
+        NSMakePoint(10, 10), widget.GetNativeWindow());
+    CGEventPost(kCGSessionEventTap, [mouse_down CGEvent]);
+    RunPendingMessages();

[jackhou1, 2015/06/02 06:33:09]

I suspect these are not actually waiting long enough for the events to be
reposted. Is there a neat way to wait for a mouse event to be received?

[tapted, 2015/06/03 00:28:37]

hm.... for these kind of events, maybe not without another event tap AFAIK. You
could use EventMonitorMac and inherit from ui::EventHandler.

Or, for another crazy idea, I just landed `ScopedSwizzleWaiter` in
native_widget_mac_unittest.mm -- you can give it basically any objective C
method on any class and spin a runloop until it gets called. E.g. you could do
this on [NSWindow setMovableByBackgroundWindow], and just wait for that call to
happen.

Then you probably wouldn't even have to make `ShouldRepostPendingLeftMouseDown`
a virtual method.

[jackhou1, 2015/06/03 04:04:44]

Just ended up using a local event monitor.

I had a look at ScopedSwizzleWaiter, but it seems a lot more complicated than
just overriding ShouldRepostPendingLeftMouseDown.

+
+    NSEvent* mouse_drag = cocoa_test_event_utils::MouseEventAtPointInWindow(
+        NSMakePoint(110, 110), NSLeftMouseDragged, widget.GetNativeWindow(),
+        3u);
+    CGEventPost(kCGSessionEventTap, [mouse_drag CGEvent]);
+    RunPendingMessages();
+    EXPECT_EQ(200, [widget.GetNativeWindow() frame].origin.x);
+
+    NSEvent* mouse_up = cocoa_test_event_utils::MouseEventAtPointInWindow(
+        NSMakePoint(110, 110), NSLeftMouseUp, widget.GetNativeWindow(), 4u);
+    CGEventPost(kCGSessionEventTap, [mouse_up CGEvent]);
+    RunPendingMessages();
+    EXPECT_EQ(200, [widget.GetNativeWindow() frame].origin.x);
+  }
+}
+
 }  // namespace views