Rejecting invalid session description

[dontcallmedom]

Current step 3.1.6 of setting a session description reads:

If the content of description is invalid, then reject p with a newly created InvalidAccessError and abort these steps.

It's not clear what kind of invalidity is meant; step 4 deals with invalid SDP, step 5 with invalid RIDs, step 7 will all other kind of errors.

[alvestrand]

For remote descriptions, I think it would be the result of "Next, the SessionDescription is parsed into a data structure, as described in Section 5.8 below. If parsing fails for any reason, processing MUST stop and an error MUST be returned."
I think the assumption is that JSEP section 5.6 returns information about what failed.

[dontcallmedom]

so, the invalid SDP step (3.1.4) would be about syntax, whereas step 3.1.6 would be about sematics verification per JSEP 5.8.3? I wonder if any implementation distinguishes between the two at the moment.

In any case, if that is indeed the distinction, I'll be happy to provide a pull request to clarify that.

[alvestrand]

I wonder how we can write a test case for it. Perhaps we should mark this "test needed"; if browsers are consistent, we can make the spec say what the browsers do.

[jan-ivar]

I think we can test this in #2514.