On Sun, Aug 30, 2009 at 4:28 PM, Brett Cannon<br...@python.org> wrote: > I am going through and running the entire test suite using importlib > to ferret out incompatibilities. I have found a bunch, although all > rather minor (raising a different exception typically; not even sure > they are worth backporting as anyone reliant on the old exceptions > might get a nasty surprise in the next micro release), and now I am > down to my last failing test suite: test_import. > > Ignoring the execution bit problem (http://bugs.python.org/issue6526 > but I have no clue why this is happening), I am bumping up against > TestPycRewriting.test_incorrect_code_name. Turns out that import > resets co_filename on a code object to __file__ before exec'ing it to > create a module's namespace in order to ignore the file name passed > into compile() for the filename argument. Now I can't change > co_filename from Python as it's a read-only attribute and thus can't > match this functionality in importlib w/o creating some custom code to > allow me to specify the co_filename somewhere (marshal.loads() or some > new function). > > My question is how important is this functionality? Do I really need > to go through and add an argument to marshal.loads or some new > function just to set co_filename to something that someone explicitly > set in a .pyc file? Or I can let this go and have this be the one > place where builtins.__import__ and importlib.__import__ differ and > just not worry about it?
ISTR that Bill Janssen once mentioned a file replication mechanism whereby there were two names for each file: the "canonical" name on a replicated read-only filesystem, and the longer "writable" name on a unique master copy. He ended up with the filenames in the .pyc files being pretty bogus (since not everyone had access to the writable filesystem). So setting co_filename to match __file__ (i.e. the name under which the module is being imported) would be a nice service in this case. In general this would happen whenever you pre-compile a bunch of .py files to .pyc/.pyo and then copy the lot to a different location. Not a completely unlikely scenario. (I was going to comment on the execution bit issue but I realized I'm not even sure if you're talking about import.c or not. :-) -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
