Copying a mock object breaks coverage utility

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Copying an instance of a Mock object with the copy module breaks the function 
of coverage for subsequent lines of code.

Win32 Python 2.5.4

Latest mock (0.7something)

Latest coverage snapshot but old versions of it do it too, like the ancient 
version that comes with eclipse pydev.

I opened a ticket in coverage as well: 
http://bitbucket.org/ned/coveragepy/issue/93/copying-a-mock-object-breaks-covera
ge#comment-262518

Original issue reported on code.google.com by jeff.lau...@gmail.com on 7 Oct 2010 at 4:35

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Original comment by jeff.lau...@gmail.com on 7 Oct 2010 at 4:37

Attachments:

• test_bug.py
• output

[GoogleCodeExporter]

This is due to an infinite recursion in Mock.__getattr__.  Add this to the top 
to fix the problem:

    def __getattr__(self, name):
        if name == "_methods":
            raise AttributeError(name)

Original comment by ned...@gmail.com on 7 Oct 2010 at 2:12

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Original comment by fuzzyman on 7 Oct 2010 at 2:23

• Changed state: Accepted
• Added labels: Milestone-Release0.7

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PS: a longer write-up of the issue: 
http://nedbatchelder.com/blog/201010/surprising_getattr_recursion.html

Original comment by ned...@gmail.com on 8 Oct 2010 at 10:35

[GoogleCodeExporter]

Fixed, but the test is a bit brutal (call sys.setrecursionlimit(sys.maxint) and 
copying a Mock segfaults without the fix). I did try the sys.settrace trick, 
but for some reason that didn't work (the trace function wasn't removed during 
the test even after the recursion).

Original comment by fuzzyman on 18 Oct 2010 at 9:36

• Changed state: Fixed