How to create parametric tests with Ava

Question

Coming from Python, I am used to this syntax when writing parametric tests (hope it is self-explanatory):

@pytest.mark.parametrize('a', [0, 1, 2])
@pytest.mark.parametrize('b', [0, 1, 2])
def test_sum(a, b):
    assert sum(a, b) == a + b

The testing framework will then run test_sum() for each combination of a and b , considering each combination as a different test (ie: the 9 combinations can fail/pass independently).

I have been playing around with Ava and, using macros, I can easily run the same test with different parameters:

import test from "ava";

function sum(a, b) {
    return a + b;
}

function macroSum(t, a, b) {
    t.is(sum(a, b), a + b);
}
macroSum.title = (providedTitle = "", a, b) =>
    `${providedTitle}: ${a} + ${b}`

test(macroSum, 0, 0);
test(macroSum, 0, 1);
test(macroSum, 0, 2);
test(macroSum, 1, 0);
test(macroSum, 1, 1);
test(macroSum, 1, 2);
test(macroSum, 2, 0);
test(macroSum, 2, 1);
test(macroSum, 2, 2);

The only problem is that I need to call test() multiple times explicitly. Is there any way I could do what I am used to do in Python? (declare a list of values for each parameter and let the framework combine them and run all the combinations for me)

Note it is not the same as embedding a loop inside a test. With parametric tests each combination is a separate test to the framework, with a different title/identifier and which can fail/pass independently of the other parameter combinations.

That means, what I am looking for is not a single test like:

test('all combinations', t => {
  [0, 1, 2].forEach(a => {
    [0, 1, 2].forEach(b => {
      t.is(sum(a, b), a + b);
    });
  });
});

Answer 1

No. Your best bet is to loop over an array of parameters:

for (const params of [
  [1, 0],
  [1, 1],
]) {
  test(macroSum, ...params)
}