Index: b/test/formats/test_id3.py
===================================================================
--- a/test/formats/test_id3.py
+++ b/test/formats/test_id3.py
@@ -266,5 +266,5 @@
         def test_rename_txxx_tags(self):
             file_path = os.path.join('test', 'data', 'test-id3-rename-tags.mp3')
-            filename = self.copy_file_tmp(file_path, 'mp3')
+            filename = self.copy_file_tmp(file_path, '.mp3')
             raw_metadata = load_raw(filename)
             self.assertIn('TXXX:Artists', raw_metadata)
f='/guix/'>guix</a></td><td class='form'><form method='get'>
<input type='hidden' name='id' value='a9ee95aec119601332875d9c4becef2331780fee'/><select name='h' onchange='this.form.submit();'>
<option value='koszko' selected='selected'>koszko</option>
<option value='koszko-scripts'>koszko-scripts</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=a9ee95aec119601332875d9c4becef2331780fee'>refs</a><a class='active' href='/guix/log/gnu/packages/solidity.scm'>log</a><a href='/guix/tree/gnu/packages/solidity.scm?id=a9ee95aec119601332875d9c4becef2331780fee'>tree</a><a href='/guix/commit/gnu/packages/solidity.scm?id=a9ee95aec119601332875d9c4becef2331780fee'>commit</a><a href='/guix/diff/gnu/packages/solidity.scm?id=a9ee95aec119601332875d9c4becef2331780fee'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages/solidity.scm'>
<input type='hidden' name='id' value='a9ee95aec119601332875d9c4becef2331780fee'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=a9ee95aec119601332875d9c4becef2331780fee'>root</a>/<a href='/guix/log/gnu?id=a9ee95aec119601332875d9c4becef2331780fee'>gnu</a>/<a href='/guix/log/gnu/packages?id=a9ee95aec119601332875d9c4becef2331780fee'>packages</a>/<a href='/guix/log/gnu/packages/solidity.scm?id=a9ee95aec119601332875d9c4becef2331780fee'>solidity.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/solidity.scm?id=a9ee95aec119601332875d9c4becef2331780fee&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>