completion-listener.spec.ts

import { TestScheduler } from 'rxjs/testing';

import { CloseEvent } from './command';
import { CompletionListener, SuccessCondition } from './completion-listener';
import { createFakeCloseEvent, FakeCommand } from './fixtures/fake-command';

let commands: FakeCommand[];
let scheduler: TestScheduler;
beforeEach(() => {
    commands = [
        new FakeCommand('foo', 'echo', 0),
        new FakeCommand('bar', 'echo', 1),
        new FakeCommand('baz', 'echo', 2),
    ];
    scheduler = new TestScheduler(() => true);
});

const createController = (successCondition?: SuccessCondition) =>
    new CompletionListener({
        successCondition,
        scheduler,
    });

const emitFakeCloseEvent = (command: FakeCommand, event?: Partial<CloseEvent>) => {
    const fakeEvent = createFakeCloseEvent({ ...event, command, index: command.index });
    command.state = 'exited';
    command.close.next(fakeEvent);
    return fakeEvent;
};

const flushPromises = () => new Promise((resolve) => setTimeout(resolve, 0));

describe('listen', () => {
    it('completes only when commands emit a close event, returns close event', async () => {
        const abortCtrl = new AbortController();
        const result = createController('all').listen(commands, abortCtrl.signal);

        commands[0].state = 'started';
        abortCtrl.abort();

        const event = emitFakeCloseEvent(commands[0]);
        scheduler.flush();

        await expect(result).resolves.toHaveLength(1);
        await expect(result).resolves.toEqual([event]);
    });

    it('completes when abort signal is received and command is stopped, returns nothing', async () => {
        const abortCtrl = new AbortController();
        // Use success condition = first to test index access when there are no close events
        const result = createController('first').listen([new FakeCommand()], abortCtrl.signal);

        abortCtrl.abort();
        scheduler.flush();

        await expect(result).resolves.toHaveLength(0);
    });

    it('check for success once all commands have emitted at least a single close event', async () => {
        const finallyCallback = jest.fn();
        const result = createController().listen(commands).finally(finallyCallback);

        // Emitting multiple close events to mimic calling command `kill/start` APIs.
        emitFakeCloseEvent(commands[0]);
        emitFakeCloseEvent(commands[0]);
        emitFakeCloseEvent(commands[0]);

        scheduler.flush();
        // A broken implementantion will have called finallyCallback only after flushing promises
        await flushPromises();
        expect(finallyCallback).not.toHaveBeenCalled();

        emitFakeCloseEvent(commands[1]);
        emitFakeCloseEvent(commands[2]);

        scheduler.flush();

        await expect(result).resolves.toEqual(expect.anything());
        expect(finallyCallback).toHaveBeenCalled();
    });

    it('takes last event emitted from each command', async () => {
        const result = createController().listen(commands);

        emitFakeCloseEvent(commands[0], { exitCode: 0 });
        emitFakeCloseEvent(commands[0], { exitCode: 1 });
        emitFakeCloseEvent(commands[1], { exitCode: 0 });
        emitFakeCloseEvent(commands[2], { exitCode: 0 });

        scheduler.flush();

        await expect(result).rejects.toEqual(expect.anything());
    });

    it('waits for manually restarted events to close', async () => {
        const finallyCallback = jest.fn();
        const result = createController().listen(commands).finally(finallyCallback);

        emitFakeCloseEvent(commands[0]);
        commands[0].state = 'started';
        emitFakeCloseEvent(commands[1]);
        emitFakeCloseEvent(commands[2]);

        scheduler.flush();
        // A broken implementantion will have called finallyCallback only after flushing promises
        await flushPromises();
        expect(finallyCallback).not.toHaveBeenCalled();

        commands[0].state = 'exited';
        emitFakeCloseEvent(commands[0]);
        scheduler.flush();

        await expect(result).resolves.toEqual(expect.anything());
        expect(finallyCallback).toHaveBeenCalled();
    });
});

describe('Detect commands exit conditions', () => {
    describe('with default success condition set', () => {
        it('succeeds if all processes exited with code 0', () => {
            const result = createController().listen(commands);

            commands[0].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[1].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[2].close.next(createFakeCloseEvent({ exitCode: 0 }));

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it('fails if one of the processes exited with non-0 code', () => {
            const result = createController().listen(commands);

            commands[0].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[1].close.next(createFakeCloseEvent({ exitCode: 1 }));
            commands[2].close.next(createFakeCloseEvent({ exitCode: 0 }));

            scheduler.flush();

            return expect(result).rejects.toEqual(expect.anything());
        });
    });

    describe('with success condition set to first', () => {
        it('succeeds if first process to exit has code 0', () => {
            const result = createController('first').listen(commands);

            commands[1].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[0].close.next(createFakeCloseEvent({ exitCode: 1 }));
            commands[2].close.next(createFakeCloseEvent({ exitCode: 1 }));

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it('fails if first process to exit has non-0 code', () => {
            const result = createController('first').listen(commands);

            commands[1].close.next(createFakeCloseEvent({ exitCode: 1 }));
            commands[0].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[2].close.next(createFakeCloseEvent({ exitCode: 0 }));

            scheduler.flush();

            return expect(result).rejects.toEqual(expect.anything());
        });
    });

    describe('with success condition set to last', () => {
        it('succeeds if last process to exit has code 0', () => {
            const result = createController('last').listen(commands);

            commands[1].close.next(createFakeCloseEvent({ exitCode: 1 }));
            commands[0].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[2].close.next(createFakeCloseEvent({ exitCode: 0 }));

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it('fails if last process to exit has non-0 code', () => {
            const result = createController('last').listen(commands);

            commands[1].close.next(createFakeCloseEvent({ exitCode: 0 }));
            commands[0].close.next(createFakeCloseEvent({ exitCode: 1 }));
            commands[2].close.next(createFakeCloseEvent({ exitCode: 1 }));

            scheduler.flush();

            return expect(result).rejects.toEqual(expect.anything());
        });
    });

    describe.each([
        // Use the middle command for both cases to make it more difficult to make a mess up
        // in the implementation cause false passes.
        ['command-bar' as const, 'bar'],
        ['command-1' as const, 1],
    ])('with success condition set to %s', (condition, nameOrIndex) => {
        it(`succeeds if command ${nameOrIndex} exits with code 0`, () => {
            const result = createController(condition).listen(commands);

            emitFakeCloseEvent(commands[0], { exitCode: 1 });
            emitFakeCloseEvent(commands[1], { exitCode: 0 });
            emitFakeCloseEvent(commands[2], { exitCode: 1 });

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it(`succeeds if all commands ${nameOrIndex} exit with code 0`, () => {
            commands = [commands[0], commands[1], commands[1]];
            const result = createController(condition).listen(commands);

            emitFakeCloseEvent(commands[0], { exitCode: 1 });
            emitFakeCloseEvent(commands[1], { exitCode: 0 });
            emitFakeCloseEvent(commands[2], { exitCode: 0 });

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it(`fails if command ${nameOrIndex} exits with non-0 code`, () => {
            const result = createController(condition).listen(commands);

            emitFakeCloseEvent(commands[0], { exitCode: 0 });
            emitFakeCloseEvent(commands[1], { exitCode: 1 });
            emitFakeCloseEvent(commands[2], { exitCode: 0 });

            scheduler.flush();

            return expect(result).rejects.toEqual(expect.anything());
        });

        it(`fails if some commands ${nameOrIndex} exit with non-0 code`, () => {
            const result = createController(condition).listen(commands);

            emitFakeCloseEvent(commands[0], { exitCode: 1 });
            emitFakeCloseEvent(commands[1], { exitCode: 0 });
            emitFakeCloseEvent(commands[2], { exitCode: 1 });

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it(`fails if command ${nameOrIndex} doesn't exist`, () => {
            const result = createController(condition).listen([commands[0]]);

            emitFakeCloseEvent(commands[0], { exitCode: 0 });
            scheduler.flush();

            return expect(result).rejects.toEqual(expect.anything());
        });
    });

    describe.each([
        // Use the middle command for both cases to make it more difficult to make a mess up
        // in the implementation cause false passes.
        ['!command-bar' as const, 'bar'],
        ['!command-1' as const, 1],
    ])('with success condition set to %s', (condition, nameOrIndex) => {
        it(`succeeds if all commands but ${nameOrIndex} exit with code 0`, () => {
            const result = createController(condition).listen(commands);

            emitFakeCloseEvent(commands[0], { exitCode: 0 });
            emitFakeCloseEvent(commands[1], { exitCode: 1 });
            emitFakeCloseEvent(commands[2], { exitCode: 0 });

            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });

        it(`fails if any commands but ${nameOrIndex} exit with non-0 code`, () => {
            const result = createController(condition).listen(commands);

            emitFakeCloseEvent(commands[0], { exitCode: 1 });
            emitFakeCloseEvent(commands[1], { exitCode: 1 });
            emitFakeCloseEvent(commands[2], { exitCode: 0 });

            scheduler.flush();

            return expect(result).rejects.toEqual(expect.anything());
        });

        it(`succeeds if command ${nameOrIndex} doesn't exist`, () => {
            const result = createController(condition).listen([commands[0]]);

            emitFakeCloseEvent(commands[0], { exitCode: 0 });
            scheduler.flush();

            return expect(result).resolves.toEqual(expect.anything());
        });
    });
});