Trigger exception debug events on Promise reject.

Trigger exception debug events on Promise reject.

R=rossberg@chromium.org, aandrey@chromium.org
BUG=393913
LOG=Y

Committed: https://code.google.com/p/v8/source/detail?r=22913

[Yang, 2014-08-05 08:43:19]

On 2014/08/05 08:39:01, Yang wrote:

Additional less important changes:
- the promise is always passed to the debug listener as part of the exception
debug event, regardless of whether the exception is caught or uncaught.
- using custom promise constructors (see
test/mjsunit/es6/debug-promises/throw-with-throw-in-reject.js for example) now
trigger two distinct exception events: one when the promise is rejected, one
when the custom reject closure throws.
- reworked the tests to be more strict: we now use Object.observe to hook into
the processing loop to be able to assert things after promise handling is fully
done.
- moved all of those tests to es6/debug-promises folder

[aandrey, 2014-08-05 11:59:39]

looking good, but i don't know V8 code well

mind adding a test case with thennable?

var q = p.then(function(v) {
  return { then: function() { boom; }  };
});

https://codereview.chromium.org/440773004/diff/1/src/debug.cc
File src/debug.cc (right):

https://codereview.chromium.org/440773004/diff/1/src/debug.cc#newcode2586
src/debug.cc:2586: bool hasreject =
PromiseHasRejectHandler(Handle<JSObject>::cast(promise));
hasreject -> has_reject

https://codereview.chromium.org/440773004/diff/1/test/mjsunit/es6/debug-promi...
File test/mjsunit/es6/debug-promises/reject-uncaught-all.js (right):

https://codereview.chromium.org/440773004/diff/1/test/mjsunit/es6/debug-promi...
test/mjsunit/es6/debug-promises/reject-uncaught-all.js:28: if (event ==
Debug.DebugEvent.AsyncTaskEvent) return;
can be dropped

[Yang, 2014-08-05 12:56:04]

Thanks for the review. As already discussed, the thennable bug will be fixed
separately from this CL.

https://codereview.chromium.org/440773004/diff/1/src/debug.cc
File src/debug.cc (right):

https://codereview.chromium.org/440773004/diff/1/src/debug.cc#newcode2586
src/debug.cc:2586: bool hasreject =
PromiseHasRejectHandler(Handle<JSObject>::cast(promise));
On 2014/08/05 11:59:39, aandrey wrote:
> hasreject -> has_reject

Removed this interim result entirely.

https://codereview.chromium.org/440773004/diff/1/test/mjsunit/es6/debug-promi...
File test/mjsunit/es6/debug-promises/reject-uncaught-all.js (right):

https://codereview.chromium.org/440773004/diff/1/test/mjsunit/es6/debug-promi...
test/mjsunit/es6/debug-promises/reject-uncaught-all.js:28: if (event ==
Debug.DebugEvent.AsyncTaskEvent) return;
On 2014/08/05 11:59:39, aandrey wrote:
> can be dropped

Done.

[rossberg, 2014-08-05 13:35:08]

LGTM with nits

https://codereview.chromium.org/440773004/diff/1/src/promise.js
File src/promise.js (right):

https://codereview.chromium.org/440773004/diff/1/src/promise.js#newcode35
src/promise.js:35: var PromiseHasRejectHandler;
Nit: move this up to the other Promise* vars.

Though, in fact, better remove all those vars and turn the assignments below
into var statements.

https://codereview.chromium.org/440773004/diff/1/src/promise.js#newcode327
src/promise.js:327: var queue = GET_PRIVATE(this, promiseOnReject);
Nit: move this line down by 2.

https://codereview.chromium.org/440773004/diff/1/src/promise.js#newcode330
src/promise.js:330: // If already rejected/resolved, the handlers have already
been fired.
If the status isn't 0 then the queue should be undefined anyway, so this extra
check shouldn't be needed.

[Yang, 2014-08-06 09:36:23]

https://codereview.chromium.org/440773004/diff/1/src/promise.js
File src/promise.js (right):

https://codereview.chromium.org/440773004/diff/1/src/promise.js#newcode35
src/promise.js:35: var PromiseHasRejectHandler;
On 2014/08/05 13:35:08, rossberg wrote:
> Nit: move this up to the other Promise* vars.
> 
> Though, in fact, better remove all those vars and turn the assignments below
> into var statements.

Done.

https://codereview.chromium.org/440773004/diff/1/src/promise.js#newcode327
src/promise.js:327: var queue = GET_PRIVATE(this, promiseOnReject);
On 2014/08/05 13:35:08, rossberg wrote:
> Nit: move this line down by 2.

Done.

https://codereview.chromium.org/440773004/diff/1/src/promise.js#newcode330
src/promise.js:330: // If already rejected/resolved, the handlers have already
been fired.
On 2014/08/05 13:35:08, rossberg wrote:
> If the status isn't 0 then the queue should be undefined anyway, so this extra
> check shouldn't be needed.

Done.

[Yang, 2014-08-06 09:42:36]

Committed patchset #3 manually as 22913 (presubmit successful).