fix(test): add patchelf to dev dependencies for testing

[bepri]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.71%. Comparing base (654871d) to head (3248e55).
Report is 633 commits behind head on main.

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HEAD has 1 upload less than BASE

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Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5135      +/-   ##
==========================================
- Coverage   94.88%   89.71%   -5.17%     
==========================================
  Files         658      342     -316     
  Lines       55189    22640   -32549     
==========================================
- Hits        52364    20311   -32053     
+ Misses       2825     2329     -496     

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[dariuszd21]

I'm quite curious what exactly this PR fixes?

[dariuszd21]

As far as I know requirements*.txt files are auto-generated and we keep dependencies in pyproject.toml or setup.py.
If I'm not mistaken this dependency should be added here, and then you should run tools/freeze-requirements.sh script.
https://github.com/canonical/snapcraft/blob/main/setup.py#L61

[bepri]

I'm quite curious what exactly this PR fixes?

I noticed that after a fresh clone, tox -f test would fail on multiple cases from patchelf not being installed. I mentioned it to Callahan and it was explained that we were using the apt package of patchelf, which was part of a weird software supply chain of us packaging our own patchelf with Snapcraft. He suggested I open this PR as a first step towards making this work without our own patchelf and setup script.

"Fix" was probably not the right commit message to include here - I made it before I understood the scope of this.

[mr-cal]

He suggested I open this PR as a first step towards making this work without our own patchelf and setup script.

Thanks for making this PR, this is a good place to discuss.

I'm not sure of the right path forward. To be totally correct, we would need to build and install this version of patchelf: https://github.com/canonical/patchelf/tree/0.9%2Bsnapcraft as that's what snapcraft uses in it's own snap. I haven't checked what is different between it and the upstream implementation.

I prefer using patchelf as a python package over a system package to keep snapcraft's dev deps more contained. On the other hand, if you clone this repo, install the install deps only and try to run in destructive mode then snapcraft would fail because patchelf would still be missing.

Finally, I don't like that we have unit tests that require patchelf.