3477 Do not install vcpython27 during Windows CI steps

[sajith]

Fixes 3477: with zfec 1.5.4 1.5.5, wheel packages for Windows is available now. Installing a compiler is no longer necessary.

Update, on Nov 12 2020: Turned out that zfec 1.5.4 wheel package for Windows + Python 2.7 was broken. I have tested zfec 1.5.5 a little more on Windows. I updated cibuildwheel version that builds zfec packages, added a step to check that the package cibuildwheel just built is actually usable, and did some manual testing on Windows and macOS. Finally, re-running Tahoe's test suite on GitHub Actions confirms that this time zfec is usable.

[sajith]

Getting this error on Windows:

zfec==1.5.4
zipp==1.2.0
zope.interface==5.1.2
py27-coverage run-test: commands[1] | tahoe --version
tahoe-lafs: 1.14.0.post1545 [HEAD: eb44944e0d3dc7711e5662ecbeec0873934821ea]
foolscap: 0.13.1
zfec: None [(<type 'exceptions.ImportError'>, 'DLL load failed: %1 is not a valid Win32 application.', ('d:\\a\\tahoe-lafs\\tahoe-lafs\\.tox\\py27-coverage\\lib\\site-packages\\zfec\\__init__.py', 13, '<module>', 'from ._fec import Encoder, Decoder, Error'))]

Looks like cibuildwheel did not build DLLs on Windows. Uh oh.

[codecov]

Codecov Report

Merging #862 (525f220) into master (4d56b5f) will decrease coverage by 1%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #862    +/-   ##
=======================================
- Coverage      92%     91%    -1%     
=======================================
  Files         157     157            
  Lines       27532   27532            
  Branches     4125    3922   -203     
=======================================
- Hits        25353   25187   -166     
- Misses       1505    1585    +80     
- Partials      674     760    +86     

Impacted Files	Coverage Δ
src/allmydata/util/humanreadable.py	65% <0%> (-16%)	⬇️
src/allmydata/_monkeypatch.py	86% <0%> (-14%)	⬇️
src/allmydata/crypto/__init__.py	86% <0%> (-14%)	⬇️
src/allmydata/immutable/downloader/__init__.py	86% <0%> (-14%)	⬇️
src/allmydata/storage/common.py	88% <0%> (-12%)	⬇️
src/allmydata/crypto/error.py	89% <0%> (-11%)	⬇️
src/allmydata/util/_python3.py	89% <0%> (-11%)	⬇️
src/allmydata/util/assertutil.py	89% <0%> (-11%)	⬇️
src/allmydata/web/common_py3.py	86% <0%> (-9%)	⬇️
src/allmydata/crypto/util.py	92% <0%> (-8%)	⬇️
... and 61 more

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[exarkun]

Looks great! Assuming there are no lingering zfec packaging issues that might cause problems later on, it seems like this should be merged?

[sajith]

Assuming there are no lingering zfec packaging issues that might cause problems later on

Sorry to respond in meme, but this is the only response I can think of:

I will test things once again locally, just to be sure, before hitting the merge button.

[sajith]

Did some more local testing of zfec 1.5.5 on Linux, Windows, and macOS, and things look okay. I had also added a testing step in zfec packaging CI, which hopefully should catch any future breakages.