721260 - Uncaught exceptions in async script can break Marionette

Status: RESOLVED FIXED

(Remote Protocol :: Marionette, defect)

Description

[Jonathan Griffin (:jgriffin)]

Marionette currently doesn't catch async exceptions which are raised in secondary script frames, and these exceptions cause Marionette to hang.

To reproduce, you can run a script like this:

self.marionette.set_context("chrome")
self.marionette.set_script_timeout(10000)
self.marionette.execute_async_script("""
setTimeout(function() {
  foo();
  marionetteScriptFinished(true);
}, 1000);
""")

To fix this we should:

1 - update the marionette client with timeout handling, so that it will timeout after X seconds if it doesn't receive a response from the server; ideally X would be the same as the script timeout
2 - potentially override window.onerror while scripts are executing, so we can catch and deal with these exceptions without bad things happening

Comment 1

[Jonathan Griffin (:jgriffin)]

See bug 718205 also

Comment 2

[Malini Das [:mdas] - Away, not checking bugmail]

Fixed now, but content errors don't print out a stack trace or any useful error right now. Opened Bug 722596 to address this.