Clock - extreme values test cases?

[kukimik]

What do you think about adding tests that check the program works correctly for extreme values of hours and minutes, i.e.: -9_223_372_036_854_775_808 and 9_223_372_036_854_775_807?

On the one hand, it is simple and elegant to define subtract in terms of add by setting:

subtract = \clock, {hours, minutes} -> add clock {hours : -hours, minutes : -minutes}

and in practice this is often the "right" thing to do. This approach teaches code reuse.

On the other hand, subtract defined as above will fail if either hours or minutes have value -9_223_372_036_854_775_808. If this case is included in the tests, it can teach being careful about overflows.

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Also, for such inputs some reasonable programs will fail at converting hours to minutes and other similar operations.

[ageron]

Great idea! Would you like to submit a PR or would you prefer I do it (I'm fine either way)? Adding extra tests requires adding a .meta/additional_tests.json file, then you can iterate over these test cases at the end of template.j2 using {% for case in additional_cases %}...{% endfor %}, see #149 for an example. Then you can generate the new test file by running bin/generate_tests.py clock. You may need to install Python and the libraries listed in requirements-generator.txt (using python -m pip install -r requirements-generator.txt).

[kukimik]

Thanks for your kind words! And I really appreciate the instructions you gave, I think it's a very good approach towards new contributors. Unfortunately I've been feeling somewhat overloaded recently, and I'd rather not add this to my TODO list. So if you are fine with creating a PR, that would be great.

[ageron]

Hi @kukimik ,
I've submitted PR #155 if you want to take a look? It complicates the solution quite a bit, so I'm thinking it might be better to test that the program either returns Ok with the correct answer, or an Err, but never crashes. This way the users learn to be careful about overflows, but they can choose to fully support extreme values, or to return an Err when the input is larger than some threshold (if they're a bit lazy). Wdyt?

[kukimik]

@ageron Thanks, I'll take a look at it in a few days.

[kukimik]

Looks like I'm late. Sorry. Anyway, thanks for handling this!

[ageron]

No worries at all, thanks for the suggestion!