jest/e2e/explicit-resource-management/__tests__/index.js

48 lines
1.5 KiB
JavaScript

/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
const TestClass = require('../');
const localClass = new TestClass();
it('restores a mock after a test if it is mocked with a `using` declaration', () => {
using mock = jest.spyOn(localClass, 'test').mockImplementation(() => 'ABCD');
expect(localClass.test()).toBe('ABCD');
expect(localClass.test).toHaveBeenCalledTimes(1);
expect(jest.isMockFunction(localClass.test)).toBeTruthy();
});
it('only sees the unmocked class', () => {
expect(localClass.test()).toBe('12345');
expect(localClass.test.mock).toBeUndefined();
expect(jest.isMockFunction(localClass.test)).toBeFalsy();
});
test('also works just with scoped code blocks', () => {
const scopedInstance = new TestClass();
{
using mock = jest
.spyOn(scopedInstance, 'test')
.mockImplementation(() => 'ABCD');
expect(scopedInstance.test()).toBe('ABCD');
expect(scopedInstance.test).toHaveBeenCalledTimes(1);
expect(jest.isMockFunction(scopedInstance.test)).toBeTruthy();
}
expect(scopedInstance.test()).toBe('12345');
expect(scopedInstance.test.mock).toBeUndefined();
expect(jest.isMockFunction(scopedInstance.test)).toBeFalsy();
});
it('jest.fn state should be restored with the `using` keyword', () => {
const mock = jest.fn();
{
using inScope = mock.mockReturnValue(2);
expect(inScope()).toBe(2);
expect(mock()).toBe(2);
}
expect(mock()).not.toBe(2);
});