utils: add check_binary_linkage function

[alebcay]

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This PR adds Utils::check_binary_linkage, which is a helper-function that is already used in some (primarily Rust-based) formulae.

The function is more or less copied verbatim, except types are loosened to accept String or Pathname. An optional prefix parameter can also be set to change the filtering behavior - this flag really only exists because we have to tweak the filtering behavior a bit in the test. Maybe we can just not do any filtering and that'll be fine - but for now I've kept it as close to the original as possible.

Open to suggestions all around, but I'm a bit extra miffed about:

• Where would be the best place to put this file, and the file name. There didn't appear to be another file in utils that seemed like a good place, so I created a new one.
• The tests still feel a bit clunky to me and I think there's probably room for improvement. Note that we set prefix in invocations to Utils::check_binary_linkage because in the test environment, HOMEBREW_CELLAR is a sibling to HOMEBREW_PREFIX, not a child, so filtering on HOMEBREW_PREFIX will exclude all the libraries in HOMEBREW_CELLAR, unlike in a real Homebrew installation where the cellar is in HOMEBREW_PREFIX/"Cellar".

[MikeMcQuaid]

Looks good to me if suggestion is applied (or similar naming to end in ?). If you're happy to apply suggestion as-is: feel free to merge without a rereview.

[alebcay]

• Renamed the function to binary_linked_to_library?
• Would appreciate some ideas on the test failure. The two added test cases seem to pass locally for me on macOS and in ubuntu22.04 brew container. Looks like the compilation of the test program is failing, but I'm not able to reproduce the failure (or would be helpful to get some verbose/debug output for why the command is failing)

[Rylan12]

The only thing: is it worth adding two integration tests for this? I know in the past we've tried to limit integration tests because they're slow, but that may have changed now (it's been a while since I've reviewed a test-related Homebrew/brew PR)

I wonder if it's possible to test the function outside of a formula context to avoid needing to spin up the brew environment. Maybe just using a temporary directory and then running the shell commands there?

[Rylan12]

Note that we set prefix in invocations to Utils::check_binary_linkage because in the test environment, HOMEBREW_CELLAR is a sibling to HOMEBREW_PREFIX, not a child, so filtering on HOMEBREW_PREFIX will exclude all the libraries in HOMEBREW_CELLAR, unlike in a real Homebrew installation where the cellar is in HOMEBREW_PREFIX/"Cellar".

I opened #19134 to move the test cellar to HOMEBREW_PREFIX/"Cellar" which might remove the need for this

[MikeMcQuaid]

The only thing: is it worth adding two integration tests for this? I know in the past we've tried to limit integration tests because they're slow, but that may have changed now (it's been a while since I've reviewed a test-related Homebrew/brew PR)

No, I still agree with that. I think a 1-2 unit tests should be sufficient here.

[alebcay]

I opened #19134 to move the test cellar to HOMEBREW_PREFIX/"Cellar" which might remove the need for this

Thank you, updated this PR to remove the prefix parameter altogether, since it should work reliably with prefix = HOMEBREW_PREFIX.

I wonder if it's possible to test the function outside of a formula context to avoid needing to spin up the brew environment. Maybe just using a temporary directory and then running the shell commands there?

I did initially think about this, the challenge was invoking the compiler outside of a formula context to produce the libraries/binary to test with. I will revisit this and see if it could be improved.

Updated the test to run outside of a formula context. Still facing challenges with setting the rpath/dependency paths in the binary, which is something that the formula context usually takes care of.

[MikeMcQuaid]

Thanks @alebcay!