[Python-Dev] Relative path in co_filename for zipped modules

[Vitaly Murashev]

This bug has been reported as http://bugs.python.org/issue18307 over a
month ago
Аnd I've found out the root cause of this issue so far. Unit-test and patch
are suggested.
Without patch test fails, with patch - passed.



On Wed, Jun 26, 2013 at 12:11 AM, Vitaly Murashev <vitaly.murashev at gmail.com
> wrote:

> Dear Python developers community,
>
> Recently I found out that it not possible to debug python code if it
> is a part of zip-module.
> Python version being used is 3.3.0
>
> Well known GUI debuggers like Eclipse+PyDev or PyCharm are unable to
> start debugging and give the following warning:
> ---
> pydev debugger: CRITICAL WARNING: This version of python seems to be
> incorrectly compiled (internal generated filenames are not absolute)
> pydev debugger: The debugger may still function, but it will work
> slower and may miss breakpoints.
> ---
> So I started my own investigation of this issue and results are the
> following.
>
> At first I took traditional python debugger 'pdb' to analyze how it
> behaves during debugging of zipped module.
> 'pdb' showed me some backtaces and filename part for stack entries
> looks malformed.
> I expected something like
> 'full-path-to-zip-dir/my_zipped_module.zip/subdir/test_module.py'
> but realy it looks like 'full-path-to-current-dir/subdir/test_module.py'
>
> Source code in pdb.py and bdb.py (which one are a part of python
> stdlib) gave me the answer why it happens.
>
> The root cause are inside Bdb.format_stack_entry() + Bdb.canonic()
>
> Please take a look at the following line inside 'format_stack_entry'
> method:
>
>     filename = self.canonic(frame.f_code.co_filename)
>
> For zipped module variable 'frame.f_code.co_filename' holds _relative_
> file path started from the root of zip archive like
> 'subdir/test_module.py'
> And as result Bdb.canonic() method gives what we have -
> 'full-path-to-current-dir/subdir/test_module.py'
> ---
> So my final question.
> Could anyone confirm that it is a bug in python core subsystem which
> one is responsible for loading zipped modules,
> or something is wrong with my zipped module ?
>
> If it is a bug could you please submit it into official python bugtracker ?
> I never did it before and afraid to do something wrong.
>
> Thanks,
> Vitaly Murashev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20130916/5a2114c0/attachment.html>