.m4a files should use audio/mp4 MIME type, not audio/mpeg

Adding steps to reproduce

Could we add a simple test case for this? Not sure if there is one that could be expanded?

This is a tricky one to decide tests for. We don't have any tests for the ExtensionMimeGuesser that I can see.

We do have a test for the Audio Media source with MediaSourceAudioVideoTest, but .m4a files aren't even part of the default configuration of an audio field.

I'm also not sure how far down the track we want to go with this. Do we add ExtensionMimeGuesser tests adhoc as issues come up? There is 350+ extensions in that list.

Verified that the code is correct, and the links above do suggest to that audio/mp4 is the correct mime for m4a files.

I'd be happy to RTBC this one, but I'll move it to review for other thoughts around tests

can add whatever kind of test is helpful, but generally we just fix the mapping bug without a test, see e.g. ✨ Add support for .FLAC, .OPUS and .AAC audio type of file with HTML 5 audio player Fixed

Thank you for sharing that. If this is something we don't test won't hold this up.

The last submitted patch, m4a-mime-type.patch, failed testing. View results →

Unrelated failure

The last submitted patch, m4a-mime-type.patch, failed testing. View results →

Yet another unrelated failure

The last submitted patch, m4a-mime-type.patch, failed testing. View results →

Random failure.

The last submitted patch, m4a-mime-type.patch, failed testing. View results →

Committed to 10.1.x and backported to 10.0.x and 9.5.x

Thanks folks!

Automatically closed - issue fixed for 2 weeks with no activity.