MIGRATIONGUIDE.md

Migration Guide

You can find here tips for migrating breaking changes.

4.0.0

The library was previously causing side effects on import. This behavior changed now and requires manual invocation of Spy.setup(). This can be done ideally in some central setup file for all of your tests.

The default configuration changed now. In order to continue using the previous defaults, you can do this:

Spy.setup({ enforceOrder: false, useGenericReactMocks: false, useOwnEquals: true });

The method Spy.initMocks was removed now as it was previously already more of an internal function. Mocks get initialized in test runner or provided beforeEach callbacks. This also means that Spy.mock, Spy.mockReactComponents cannot be invoked anymore inside the test (it) function.

The library was also doing some custom module mocking that is no longer maintainable considering that it was based on CommonJS and does not work with vitest or the new (still experimental) ESM mode from jest.

The method Spy.mockModule was removed. To achieve the same you need to transform like this:

Spy.mockModule('./my-module', 'foo'); // OLD
Spy.mock(require('./my-module'), 'foo'); // NEW
Spy.mock(require('./my-module') as typeof import('./my-module'), 'foo'); // with type safety

The method Spy.mockReactComponents uses also no build-in module mocks anymore and requires this change:

Spy.mockReactComponents('./my-module', 'MyComponent'); // OLD
Spy.mockReactComponents(require('./my-module'), 'MyComponent'); // NEW
Spy.mockReactComponents(require('./my-module') as typeof import('./my-module'), 'MyComponent'); // with type safety

Please note that it is rather recommended to use await import('./my-module') syntax with build-in type-safety that is explained in the main documentation.

Since mocks are type safe now, you might need to fix some type issues or have to cast the mocked instance to any as it was before and lose the type safety. E.g. just using require('./my-module') or this (await import('./my-module')) as any.

3.0.0

• new Spy() -> Spy()

2.0.0

• If you have previously added an own hook, which called Spy.restoreAll after each test suite, you may remove it.
• If you get troubles with the automatically added test hooks, you can override/remove it by usage of Spy.configure
• If you have used Spy.onMany you have to switch to Spy.mock. Depending on your special case, this can get aweful. Here an example, how someone could accomplish it. Let's assume this v1 code:

describe('Test', () => {
    let spy1 = new Spy();
    let spy2 = new Spy();

    beforeEach(() => {
        [spy1, spy2] = Spy.onMany(LOG, 'error', 'info');
    });

    it('logs an info if job runs', () => {
        // run the job (...)
        spy1.wasNotCalled();
        spy2.hasCallHistory('job finished');
    });
});

This can be changed to:

// I recommend to initialize mocks ouside of the describe-Block (or update to 2.1 which includes scoped mocks)
const Mock$LOG = Spy.mock(LOG, 'error', 'info');

describe('Test', () => {
    it('logs an info if job runs', () => {
        // run the job (...)
        Mock$LOG.error.wasNotCalled();
        Mock$LOG.info.hasCallHistory('job finished');
    });
});

Notice how much more readable the test code became. Have fun ✌️