fix(remote): parse comma-separated architectures

[mr-cal]

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---

2 commits:

• fix(remote): make --build-for and --build-on mutually exclusive
  • This was not working as intended (and was not tested)
  • This is only for the new remote-build and makes no changes to how legacy remote build handles these arguments
• fix(remote): parse comma-separated architectures
  • This uses the same style that legacy remote-build uses for passing architectures - a single comma-separated set

Fixes #4516
(CRAFT-2386)

[tigarmo]

Does this support something wacky like --build-for=amd64 --build-for=arm64,armhf?

[mr-cal]

Good question. When there are duplicates, argparse/craft-cli uses the last --build-{on|for}, silently ignores the other --build-{on|for}s, and always provides a single string for this lambda.

Normally I wouldn't add a test for standard behavior, but since this is a delicate situation, I added an extra unit test.

[tigarmo]

to be clear, this wouldn't be a change in behavior right? The previous code would also only use the last --build-x?

[mr-cal]

Correct, this behavior is unchanged.

The only "loss" is that snapcraft remote-build --build-for amd64 arm64 doesn't work.

And I think that "loss" is OK because it is a regression in the new remote builder: snapcraft 7 only supported comma-separated architectures, not space-separated architectures.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (ef10848) 89.18% compared to head (afb963b) 89.19%.
Report is 1 commits behind head on hotfix/8.0.

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Additional details and impacted files

@@              Coverage Diff               @@
##           hotfix/8.0    #4543      +/-   ##
==============================================
+ Coverage       89.18%   89.19%   +0.01%     
==============================================
  Files             321      322       +1     
  Lines           21763    21814      +51     
==============================================
+ Hits            19409    19457      +48     
- Misses           2354     2357       +3     

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[tigarmo]

thankss

[mr-cal]

Merging because spread test failures are completely unrelated (appears to be an issue with the devel image to be resolved via canonical/craft-providers#501