Just tried opening the editor (v1.15) via the context menu and got the following error (while running in debug mode). The editor did open successfully.
Code:
Failed to set metadata for u'The Adventures of Huckleberry Finn'
Traceback (most recent call last):
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/customize/ui.py", line 363, in set_file_type_metadata
plugin.set_metadata(stream, mi, ftype.lower().strip())
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/customize/builtins.py", line 438, in set_metadata
set_metadata(stream, mi, apply_null=self.apply_null, force_identifiers=self.force_identifiers)
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/ebooks/metadata/epub.py", line 319, in set_metadata
newopf = StringIO(reader.opf.render())
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/ebooks/metadata/opf2.py", line 1231, in render
_pretty_print(self.root)
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/ebooks/metadata/opf2.py", line 41, in _pretty_print
pretty_opf(root)
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/ebooks/oeb/polish/pretty.py", line 81, in pretty_opf
children = sorted(manifest, key=manifest_key)
File "/Users/gregoryriker/Documents/calibredev/source/src/calibre/ebooks/oeb/polish/pretty.py", line 57, in manifest_key
ext = href.rpartition('.')[-1].lower()
AttributeError: 'NoneType' object has no attribute 'rpartition'