I'm trying to test a signal which is exported from a JS module. The problem is that between tests it's changed and the tests become interdependent.
export const [launchedPressed$, pressLaunch] = createSignal<Launch>();
export const [useLaunchRocket, launchRocket$] = bind(
launchedPressed$.pipe(
switchMap(({ delaySeconds, url, status, timeoutSeconds }) => {
return status === LaunchStatus.WORKING
? of(LaunchStatus.ABORTED)
: ajax.getJSON(`${url}${delaySeconds}`).pipe(
map(() => LaunchStatus.STANDBY),
timeoutWhen(!!timeoutSeconds, (timeoutSeconds ?? 10) * 1000),
catchError(() => of(LaunchStatus.ABORTED)),
);
}),
map((status) => ({ status })),
startWith({ status: LaunchStatus.STANDBY }),
),
);
Because the signal is exported from this module it's akin to a global variable and the value is changed between tests within the test runner. This makes the values less predictable and the tests more flaky and interdependent.
it("should emit aborted when status is working and pressLaunch is called", () => {
testScheduler.run(async (helpers) => {
const { cold, expectObservable } = helpers;
const payloadA: { a: Launch } = {
a: {
delaySeconds: 1,
status: "working",
url: "www.google.com",
timeoutSeconds: 2,
},
};
const expectedA = { a: { status: "standby" }, b: { status: "aborted" } };
const source$ = cold("a", payloadA).pipe(tap((a) => pressLaunch(a)));
expectObservable(source$).toBe("a", payloadA);
expectObservable(launchRocket$).toBe("(ab)", expectedA);
});
});
it("should abort when the delay exceeds the timeout", () => {
(ajax.getJSON as jest.Mock).mockImplementation(() => of("test").pipe(delay(3000)));
testScheduler.run(async (helpers) => {
const { cold, expectObservable } = helpers;
const payloadA: { a: Launch } = {
a: {
delaySeconds: 3,
status: "standby",
url: "www.google.com",
timeoutSeconds: 2,
},
};
const expectedA = { a: { status: "standby" }, b: { status: "aborted" } };
const source$ = cold("a", payloadA).pipe(tap((a) => pressLaunch(a)));
expectObservable(source$).toBe("a", payloadA);
expectObservable(launchRocket$).toBe("a 2000ms b", expectedA);
});
})