Bug 135690 – Web Inspector: DebuggerManager commands should return promises

• Component: Web Inspector
• Status: RESOLVED FIXED

[Brian Burg]

This could include pause, resume, stepOver, stepInto, stepOut.

Note that these should add one-time listeners to the relevant DebuggerManager events, rather than returning the same promise returned by InspectorBackend commands. The latter may fire before the debugger manager has actually received the relevant event from the backend.

[Radar WebKit Bug Importer]

<rdar://problem/17942179>

[Brian Burg]

Created attachment 236318 [details]
Patch

[Brian Burg]

Comment on attachment 236318 [details]
Patch

This needs to be tested manually once debugging works again. But, feel free to review before then.

[Timothy Hatcher]

Comment on attachment 236318 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=236318&action=review

> Source/WebInspectorUI/UserInterface/Base/EventListenerSet.js:27
> +WebInspector.EventListener = function(thisObject, fireOnce)

Should be a seperate file.

> Source/WebInspectorUI/UserInterface/Controllers/DebuggerManager.js:158
> +                throw error;

Why throw?

[Brian Burg]

Comment on attachment 236318 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=236318&action=review

>> Source/WebInspectorUI/UserInterface/Base/EventListenerSet.js:27
>> +WebInspector.EventListener = function(thisObject, fireOnce)
> 
> Should be a seperate file.

ok

>> Source/WebInspectorUI/UserInterface/Controllers/DebuggerManager.js:158
>> +                throw error;
> 
> Why throw?

From a catch block, you need to re-throw an exception. Otherwise, the overall chain will be resolved instead of rejected.
We want the promise returned by this method to cause a larger chain to be rejected if any step fails.

[Timothy Hatcher]

I thought that might be the case. Still a promise noob here.

[Brian Burg]

(In reply to comment #6)
> I thought that might be the case. Still a promise noob here.

I just wrote up some such Promise gotchas on the Inspector style guide page.

[Timothy Hatcher]

Comment on attachment 236318 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=236318&action=review

> Source/WebInspectorUI/ChangeLog:26
> +        Web Inspector: Add a helper to avoid leaking single-fire event listeners in Promise chains
> +        https://bugs.webkit.org/show_bug.cgi?id=135772

Should remove this from this patch, which I think you already noticed.

[Joseph Pecoraro]

Comment on attachment 236318 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=236318&action=review

> Source/WebInspectorUI/UserInterface/Controllers/DebuggerManager.js:148
> +        listener = new WebInspector.EventListener(this, true);

Missing "var" for listener, otherwise this leaks into global scope. [Applies to multiple places in this patch].

[Brian Burg]

Committed r172412: <http://trac.webkit.org/changeset/172412>