fix: combine aliases on windows base dirs (ie: X:\) (fixes: #577)

[vaab]

Illustrating a valid fix for my issue, that is still happening ;-)

I had a (very quick) look at running the tests, but unfortunately I had a lot of tests failing on the pristine source prior to any change. So I figured I missed a lot of dependencies or information to get this running properly. I'm afraid that I couldn't check that I didn't break anything properly before submitting that code change.

If you think this code change is definitively worth it, I'll take the time to add tests to your convenience if required.

[nedbat]

@vaab Thanks for sticking with this! I took a quick look at the change, and it seems straightforward enough. The tests are passing here on GitHub, so it seems good. If you could add a test of the specific problem, that would be great!

[codecov-io]

Codecov Report

Merging #1080 (8f4e695) into master (37285cb) will decrease coverage by 0.05%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1080      +/-   ##
==========================================
- Coverage   91.30%   91.24%   -0.06%     
==========================================
  Files          90       90              
  Lines       13358    13358              
  Branches     1493     1493              
==========================================
- Hits        12196    12188       -8     
- Misses        951      959       +8     
  Partials      211      211              

Impacted Files	Coverage Δ
coverage/files.py	84.11% <100.00%> (ø)
tests/test_debug.py	90.82% <0.00%> (-7.34%)	⬇️

[vaab]

Added the test as required, kept it quite simple. Thanks for your feedback. Should I worry about the coverage drop ? It seems to happen in a test file, which was seemingly untouched by my change.

[nedbat]

@vaab no worries about the codecov drop. Ironically, I can't make heads or tails of those reports, and have turned them off.

Thanks!

[nedbat]

This is now released as part of coverage 5.4.