470845 - Create infrastructure to test processing of native mouse events

Status: RESOLVED FIXED

(Core :: Widget, defect)

Description

[Steven Michaud [:smichaud] (Retired)]

In order to write a reasonable variety of mochitests/chrometests for
widget bugs, we need to be able to allow them to synthesize native
mouse events.

This would presumably be parallel to the support we already have for
synthesizing native key events in nsIDomUtils::SendNativeMouseEvent()
and nsIWidget::SynthesizeNativeKeyEvent().

Comment 1

[Steven Michaud [:smichaud] (Retired)]

> This would presumably be parallel to the support we already have for
> synthesizing native key events in nsIDomUtils::SendNativeMouseEvent()
> and nsIWidget::SynthesizeNativeKeyEvent().

See bug 431503.

Comment 2

[Robert O'Callahan (:roc) (email my personal email if necessary)]

nsDOMWindowUtils::SendMouseEvent synthesizes nsIWidget-level events. Do you need to synthesize actual Cocoa mouse events for some reason?

Comment 3

[Steven Michaud [:smichaud] (Retired)]

(In reply to comment #2)

> Do you need to synthesize actual Cocoa mouse events for some reason?

Yes.  To allow us to write mochitests (or chrome tests and so on) for
bugs where the bug was caused by native mouse events being (somehow)
mishandled.

I should think the need for this is ... well, obvious :-)

Or am I missing something?

Comment 4

[Robert O'Callahan (:roc) (email my personal email if necessary)]

The only additional code you can test with real Cocoa events is the code that converts Cocoa events to nsMouseEvent events ... or code that only understands Cocoa events, perhaps Mac native menus or something. Is that what you have in mind?

Comment 5

[Steven Michaud [:smichaud] (Retired)]

The only specific examples I had in mind are focus bugs like bug
428405 and bug 403232.  In these cases, it's not so much the native
mouse event itself that's mishandled, but the (OS-defined and
OS-implemented) consequences of that event that are mishandled -- the
OS changes the keyboard focus from NSView object to another, but
problems arise in Gecko if this is allowed to happen.

I was able to reproduce bug 428405 using only (native) keyboard events
-- so it wasn't impossible to write a mochitest for that bug.  But
that won't always be the case (especially considering that the OS
expects a left mouse-down to change the focus).

It wouldn't be hard to write an
nsIWidget::SynthesizeNativeMouseEvent() for OS X -- I could do it
myself.  I don't (off the top of my head) know how to write one for
Windows or Linux.  But even nsIWidget::SynthesizeNativeKeyEvent() is
still only implemented on OS X and Windows (not yet on Linux).

Comment 6

[Robert O'Callahan (:roc) (email my personal email if necessary)]

OK, that makes sense.

Comment 8

[Markus Stange [:mstange]]

Attachment: v1

Comment 9

[Robert O'Callahan (:roc) (email my personal email if necessary)]

+          return frame->GetView()->GetNearestWidget(nsnull);

frame->GetWindow()

+  if (mWindow) {
+    nsIDocShell *docShell = mWindow->GetDocShell();
+    if (docShell) {
+      nsCOMPtr<nsIPresShell> presShell;
+      docShell->GetPresShell(getter_AddRefs(presShell));
+      if (presShell) {
+        nsCOMPtr<nsIContent> content = do_QueryInterface(aElement);
+        nsIFrame* frame = presShell->GetPrimaryFrameFor(content);

Why not just do content->GetCurrentDoc() (null check) ->GetPrimaryPresShell() etc?

Suppose we want to make test_native_mouse.xul work cross-platform. What would we have to do? Seems to me we might want some kind of cross-platform wrapper around sendNativeMouseEvent in EventUtils.js so that the message and modifiers can be abstracted.

Comment 10

[Markus Stange [:mstange]]

Attachment: v2

(In reply to comment #9)
> Suppose we want to make test_native_mouse.xul work cross-platform. What would
> we have to do?

I don't think test_native_mouse.xul should be cross-platform; it's very platform-specific by design. E.g. it tests not sending most mouse events to background windows, which is a Mac-ism, and it's simulating OS quirks like sending events to a window that's not under the mouse.
I've renamed it to test_native_mouse_mac.xul

I don't know how mouse events work on other platforms and if they also have an event redirection setup; if they do, maybe we can add a shared test.

> Seems to me we might want some kind of cross-platform wrapper
> around sendNativeMouseEvent in EventUtils.js so that the message and modifiers
> can be abstracted.

Maybe, but I think we can think about that when we add support for other platforms. :)

Comment 11

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Comment on attachment 400895 [details] [diff] [review]
v2

Fair enough.

Comment 12

[Markus Stange [:mstange]]

Comment on attachment 400895 [details] [diff] [review]
v2

I think I'll combine this with bug 515003. I've noticed that some comments in the test are not correct, and I don't want to go through the hassle of moving those correction back into this patch.

Comment 13

[Markus Stange [:mstange]]

http://hg.mozilla.org/mozilla-central/rev/810ee87710df