fix problem with non-exported function

[maxpohlmann]

We had a problem where Quantum could only schedule a job right after executing mix clean, but with every call to mix after that, our configured jobs were not scheduled, because function_exported?/3 returned false, even though the function still existed, but apparently was not yet exported at the time the Quantum code executed. This PR fixes this by calling Code.ensure_loaded?/1 before function_exported?/3, which actively tries to load the module before returning true if this was successful or false otherwise (e.g. if the module does not exist).

[maennchen]

This condition is quite hard to read. Can we switch it to something like this?

if Code.ensure_loaded?(m),
  do: not(function_exported?(m, f, length(args))),
  else: true

[maxpohlmann]

Thanks for the suggestion, it's definitely more readable that way. Also, thank you for reacting so quickly! 🙏

[coveralls]

Pull Request Test Coverage Report for Build 7047ec21deddb8daa1a64b6a04869c7a6d3fa56b-PR-603

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.03%) to 86.453%

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Totals
Change from base Build 0c34ca8dc6937f148b6e272dfd621251e6da8765:	0.03%
Covered Lines:	351
Relevant Lines:	406

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💛 - Coveralls

[maxpohlmann]

Thank you! :)