Rewrite of the test generator

[TheRealOwenRees]

Draft

Before I go any further, I would like some feedback on how we might handle test templates moving forward.

• I have added a test_templates directory, where test templates are now written in pure ReScript
• a utility function has been added to retrieve the input keys from the canonical data
• I have not yet implemented a way to automatically create the slug for tests (perhaps pascal case to kebab case and strip the _test part.)
• it requires both a comparator function and a string template function (genAssertionName) to be written, but then the use of these in your test template is simpler.

I have re-implemented a few of the exercises using this test generator for your review.

[github-actions]

This PR touches files which potentially affect the outcome of the tests of an exercise. This will cause all students' solutions to affected exercises to be re-tested.

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[BNAndras]

Yeah, you could pull out the slug from either the test file itself or the containing exercise folder.

[TheRealOwenRees]

Other than the feedback, is this somewhat in the direction you had previously mentioned? It is not pretty at the moment, and I will invest a lot more time into it if it is to move ahead.

[TheRealOwenRees]

I am going through the exercises one by one. Once I reach the exercises which use comparators other than equal, I will update them as highlighted in the feedback

[BNAndras]

Yeah, having the assertion functions as actual ReScript code means we can check them. As strings, we don't have that option.

[TheRealOwenRees]

I am a bit stuck here. Having the comparator functions as strings is the only way I can see to inject them into the exercise test files. Copying the old Assertions module into each exercise's test directory isn't feasible.

[TheRealOwenRees]

this is an abstracted version of the comparator function that we can use.

[TheRealOwenRees]

All tests converted to use ReScript.

[BNAndras]

Nice! Looks good to me

[TheRealOwenRees]

Happy to merge if you are. I think it's a good place to build from and continue adding more exercises