mid3v2 mangles data before adding to ID3v2 tags

[Moses Moore]

I can't add frame 'WXXX' to mp3 files; mid3v2 changes the frame name
and the frame value before writing to disk.

What I did:

    $ mid3v2 --list-raw example.mp3
    Raw IDv2 tag info for example.mp3
    TDRC(encoding=<Encoding.LATIN1: 0>, text=[u'2018'])
    TALB(encoding=<Encoding.LATIN1: 0>, text=[u'albumname'])
    TPE1(encoding=<Encoding.LATIN1: 0>, text=[u'artistname'])
    TIT2(encoding=<Encoding.LATIN1: 0>, text=[u'songtitle'])
    $ mid3v2 -h
    ...
    You can set the value for any ID3v2 frame by using '--' and then a frame ID.
    For example:
        mid3v2 --TIT3 "Monkey!" file.mp3
    ...
    $ mid3v2 --WXXX "http://ubuntu.com/" example.mp3

What I expected:

    $ mid3v2 --list-raw example.mp3
    WXXX(encoding=<Encoding.????: ?>, text=[u'http://ubuntu.com/'])
    or
    WXXX(encoding=<Encoding.????: ?>, url=u'http://ubuntu.com/')

What I saw:

    $ mid3v2 --list-raw example.mp3
    WXXX(encoding=<Encoding.UTF8: 3>, desc=u'', url=u"[u'http://ubuntu.com/']")

When I use mutagen itself to read that frame I get:

    >>> import mutagen
    >>> f = mutagen.File('example.mp3')
    >>> f.tags['WXXX']
    KeyError: 'WXXX'
    >>> f.tags['WXXX:']
    WXXX(encoding=<Encoding.UTF8: 3>, desc='', url="[u'http://ubuntu.com/']")
    >>> str(f.tags['WXXX:'])
    "[u'http://ubuntu.com/']"

I said "WXXX" not "WXXX:", and the value that mid3v2 stored was a string
of a one-item list of the actual string I told it to store.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: python-mutagen 1.38-1
ProcVersionSignature: Ubuntu 4.13.0-25.29-generic 4.13.13
Uname: Linux 4.13.0-25-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.7-0ubuntu3.7
Architecture: amd64
CurrentDesktop: XFCE
Date: Sat Mar 24 10:42:08 2018
Dependencies:

InstallationDate: Installed on 2016-06-05 (657 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
PackageArchitecture: all
SourcePackage: mutagen
UpgradeStatus: Upgraded to artful on 2017-10-22 (153 days ago)

[Moses Moore (moses-ubuntu)]

I thought it might be because 'WXXX' is for freeform url data, so I used a more official frame 'WOAS'. The frame name wasn't munged, but the value was:

    $ mid3v2 --WOAS 'https://ubuntu.org' example.mp3
    $ mid3v2 -l example.mp3
    ...
    WOAS=[u'https://ubuntu.org']

and when using mutagen directly:

    >>> import mutagen
    >>> f = mutagen.File('example.mp3')
    >>> f.tags['WOAS']
    WOAS(url="[u'https://ubuntu.org']")
    >>> str(f.tags['WOAS'])
    "[u'https://ubuntu.org']"
    >>> f.tags['WOAS'].url
    "[u'https://ubuntu.org']"

[Christoph Reiter (lazka)]

Thanks, that looks like a bug.

re "WXXX" vs "WXXX:" see https://mutagen.readthedocs.io/en/latest/user/id3.html#id3-dict-interface

[Christoph Reiter (lazka)]

https://github.com/quodlibet/mutagen/issues/344

[Christoph Reiter (lazka)]

Fixed in master: https://github.com/quodlibet/mutagen/commit/62e4dbb6c3e9268a659030090ff67a1082d2b771

If I missed anything feel free to post here or on github.