#2621 custom tag map

[elfalem]

Pull request for resolving #2621

[mention-bot]

@elfalem, thanks for your PR! By analyzing the history of the files in this pull request, we identified @geigerzaehler, @sampsyo and @pkess to be potential reviewers.

[elfalem]

I'm not sure what's going on with the tests failing with the error AttributeError: 'ReadWriteTestBase' object has no attribute 'extension. Running the entire suite of tests locally succeeds. But running those tests individually shows the same errors as Travis. This happens for my branch as well as the current master branch.

[sampsyo]

Hmm; that’s strange! But the current commit on master seems to have succeeded on Travis? I don’t see any obvious indication about what’s going wrong.

[elfalem]

I ran the tests again at different levels as follows:
one of the tests with errors from ReadWriteTestBase by itself
nosetests test.test_mediafile:ReadWriteTestBase.test_write_counters_without_total
all the tests in the class
nosetests test.test_mediafile:ReadWriteTestBase
the entire file
nosetests test.test_mediafile
the entire test suite
nosetests

I did this for the current PR branch and master and got:

Level	master	this PR
single test	error	error
test class	error	error
entire file	success	error
entire suite	success	success

I was able to narrow down the issue to the change I made in the following lines which was intended to avoid user configuration from affecting test runs.
https://github.com/elfalem/beets/blob/54b27e35c536691e792ca63e76c8683d534de495/test/test_mediafile.py#L301
https://github.com/elfalem/beets/blob/54b27e35c536691e792ca63e76c8683d534de495/test/test_mediafile.py#L406
https://github.com/elfalem/beets/blob/54b27e35c536691e792ca63e76c8683d534de495/test/test_mediafile.py#L411

I can take out those changes since they're not necessary for this PR and make this branch pass in Travis but I think there's a bigger issue of the same tests returning different results depending the level they're run.

[elfalem]

What's the best way to proceed here?

[arcresu]

@elfalem just a heads up that we're planning to split MediaFile out into a standalone Python package and git repository (see #3237). Your PR will obviously be affected by that, but your branch had already fallen out of date. Do you still have plans to work on these changes? If so it might be best to start off with the changes to MediaFile and then as a second stage look at using them in beets.

[elfalem]

Thanks for the update. It has been a while since I looked at this PR so it will require significant updates regardless

[jtpavlock]

@elfalem any chance you still have interest in working on this?

[elfalem]

@jtpavlock Unfortunately I do not.

[jtpavlock]

@elfalem no worries, maybe your work will help out someone that tries to tackle this problem in the future. I'm going to close this since it would need some serious refactoring at this point as well.