1186142 - TypeError on PeerConnection.getStats() with no arguments.

Status: RESOLVED FIXED

(Core :: WebRTC, defect, P1)

Description

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

STR:

'use strict';
new mozRTCPeerConnection().getStats().catch(e => console.error(e));

Expected result: success

Actual result: TypeError: Not enough arguments to mozRTCPeerConnection.getStats.

Regular non-strict mode saves us, because undefined gets promoted to null there, and since the argument is nullable, the right call signature (the promise one) is chosen, the call is called and succeeds. 

The selector argument to getStats needs to be nullable AND optional to work in strict mode. The spec has this (see URL), so we just need to update our webidl to fix this.

Comment 1

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

Attachment: MozReview Request: Bug 1186142 - Make selector arg optional on PeerConnection.getStats().

Bug 1186142 - Make selector arg optional on PeerConnection.getStats().

Comment 2

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 8636780 [details]
MozReview Request: Bug 1186142 - Make selector arg optional on PeerConnection.getStats().

https://reviewboard.mozilla.org/r/13705/#review12549

I don't see what strict mode has to do with this.  In non-strict mode you get the same behavior:

  <script>
    new mozRTCPeerConnection().getStats().catch(e => console.error(e));
  </script>

logs an error.

The spec's language also doesn't make sense to me; it never handles the "not passed" case.  It should probably have null as default value and change the check for an invalid selector to not happen if the value is null.  Please file a spec issue to that effect?

r=me

Comment 3

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

You're right. Pilot error on my part (I was thrown by pc.getStats(); suppressing errors).

PR for spec changes here https://github.com/w3c/webrtc-pc/pull/256

Thanks!

Comment 4

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/bc68403ba5ea

Comment 5

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/bc68403ba5ea