I have a simple passing unit test:
describe("Example", () => {
it("Return digits or empty string", () => {
let actual = SmokeTest.ProblemOne("1");
assert.equal(actual, "1");
})
})
I now wish to test many other cases (empty string, more complex inputs and edge-cases). I have read about how to implement fixtures in TypeScript but this seems like overkill for an array of test-input, expected-output values.
What is the idiomatic way to define such an array in TypeScript / Mocha?
You can just make a function that you can reuse.
function assertProblemOne(input: string, expected: string): void {
let actual = SmokeTest.ProblemOne(input);
assert.equal(expected, actual);
}
describe("Example", () => {
it("Return digits or empty string", () => {
assertProblemOne("input here", "expected result here")
})
})
However, I'm not sure that's really much better than simply.
assert.equal(SmokeTest.ProblemOne("1"), "1");
The only thing worse than debugging your code is debugging your tests. So unless there is a large amount of code that is shared between tests, I would recommend keep the code that runs in each tests as structurally simple as possible.
No special syntax is required... to parameterize tests [you can] generate them with a closure.
describe("Example", () => {
// define a closure that calls the method we are testing
const testProblemOne = ({arg, expected}) =>
function () {
const actual = SmokeTest.ProblemOne(arg);
assert.equal(actual, expected);
}
// invoke the closure for each test case
it("Empty returns empty", testProblemOne({arg: "", expected: ""}));
it("Single digit identity", testProblemOne({arg: "1", expected: "1"}));
// additional test cases here...
})
This technique avoids using foreach in favor of readability and broader IDE integration.