+
+ # XXX: In real cases InfoExtractor._parse_mpd_formats() fills up 'acodec'
+ # and 'vcodec', while in tests such information is incomplete since
+ # commit a6c2c24479e5f4827ceb06f64d855329c0a6f593
+ # test_YoutubeDL.test_youtube_format_selection is broken without
+ # this fix
+ if 'acodec' in info and 'vcodec' not in info:
+ info['vcodec'] = 'none'
+ elif 'vcodec' in info and 'acodec' not in info:
+ info['acodec'] = 'none'
+