debian-mirror-gitlab/spec/frontend/__mocks__/lodash/debounce.js
2023-05-27 22:25:52 +05:30

35 lines
1.2 KiB
JavaScript

// `lodash/debounce` has a non-trivial implementation which can lead to
// [flaky spec errors][1]. This mock simply makes `debounce` calls synchronous.
//
// In the future we could enhance this by injecting some test values in
// the function passed to it. See [this issue][2] for more information.
//
// [1]: https://gitlab.com/gitlab-org/gitlab/-/issues/212532
// [2]: https://gitlab.com/gitlab-org/gitlab/-/issues/213378
// Further reference: https://github.com/facebook/jest/issues/3465
export default (fn) => {
let id;
const debouncedFn = jest.fn(function run(...args) {
// this is calculated in runtime so beforeAll hook works in tests
const timeout = global.JEST_DEBOUNCE_THROTTLE_TIMEOUT;
if (timeout) {
id = setTimeout(() => {
fn.apply(this, args);
}, timeout);
} else {
fn.apply(this, args);
}
});
debouncedFn.cancel = jest.fn(() => {
clearTimeout(id);
});
debouncedFn.flush = jest.fn(() => {
const errorMessage =
"The .flush() method returned by lodash.debounce is not yet implemented/mocked by the mock in 'spec/frontend/__mocks__/lodash/debounce.js'.";
throw new Error(errorMessage);
});
return debouncedFn;
};