780805 - Passing a null value into the first parameter of mozGetUserMedia - NS_ERROR_INVALID_POINTER is thrown, instead of a graceful failure

Status: RESOLVED DUPLICATE of bug 1161433

(Core :: WebRTC, defect, P4)

Description

[Jason Smith [:jsmith]]

JS:

function successStream(stream) {
	alert("Success: " + stream);
}

function failStream(err) {
	alert("Failure: " + err);
}

function main()
{
    navigator.mozGetUserMedia(null, successStream, failStream);
}

Expected:

We should handle this gracefully when a null value is passed into the first parameter without dumping a nasty error in the error console.

Actual:

Nasty failure is seen in the error logs:

Timestamp: 8/6/2012 8:10:24 PM
Error: NS_ERROR_INVALID_POINTER: Component returned failure code: 0x80004003 (NS_ERROR_INVALID_POINTER) [nsIDOMNavigatorUserMedia.mozGetUserMedia]
Source File: file:///C:/Users/jsmith/Documents/Camera%20API/Simple%20Scratchpad.html
Line: 16

We should really try to handle this gracefully.

Comment 1

[Jason Smith [:jsmith]]

I'm closing this as invalid as apparently this is normal behavior for most DOM APIs upon further investigation.

Comment 2

[Masatoshi Kimura [:emk]]

getUserMedia(null, ...) shouldn't throw because the first argument of getUserMedia is nullable.
http://dev.w3.org/2011/webrtc/editor/getusermedia.html#navigatorusermedia
But this WebIDL definition is invalid because dictionary types cannot be nullable.
http://dev.w3.org/2006/webapi/WebIDL/#dfn-nullable-type
That said, a dictionary argument will accept null value even if it is not nullable.
http://dev.w3.org/2006/webapi/WebIDL/#es-dictionary
In conclusion, the spec should change |MediaStreamConstraints? constraints| to |MediaStreamConstraints constraints| and we should handle the null argument gracefully.

Comment 3

[Jason Smith [:jsmith]]

Fair enough, I'll reopen to track then.

Comment 4

[Maire Reavy [:mreavy]]

Are we correct per spec currently?

Comment 5

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

Yes.