Parameterized tests and/or custom assertion messages

[pdesjardins90]

Sometimes, testing the same code on different datasets is useful. For large datasets, writing a single test for each item in the dataset is exhausting and cumbersome.

Currently, the only smart way to do this is to write a single test, that iterates over an array of test cases:

Ensure(MyTest, testAllTheTings) {
    for (uint8_t index = 0; index < NUMBER_OF_TEST_CASES; ++index) {
        TestCase testCase = TEST_CASES[index];
        uint8_t result = thingDoer()->doThing(testCase.parameter1, testCase.parameter2);
        assert_that(result, is_equal_to(testCase.expectedResult));
    }
}

The problem with this approach is that the new assertion styles do not let you add a custom error message, resulting in error messages that do not tell you which testCase failed. Currently, the only option available is to use the legacy-style assertion assert_equal_with_message.

Adding custom error messages support to the new assertion style would fix this particular issue, but I feel like properly handling parameterized tests would be the better approach. What do you think?

[thoni56]

Thank you, Phillippe!

That's a really relevant scenario! It gives me a few ideas that I'd like to ponder for a while. If you have any more concrete ideas from your particular usecase on how to support that, please add them here.