Error with jest-canvas-mock and jest.resetAllMocks()

[qiuhanWEI]

Hi, I'm using jest.resetAllMocks() in afterEach like this:

afterEach(() => {
  jest.resetAllMocks();
});

and then, the first test case is successful but the following tests fail, because context is undefined:

const canvas: HTMLCanvasElement = document.createElement('canvas');
const context: CanvasRenderingContext2D | null = canvas.getContext('2d');

I have to hack like this:

import canvasMock from 'jest-canvas-mock/lib/mock/prototype';

afterEach(() => {
  jest.resetAllMocks();
});

beforeEach(() => {
  canvasMock();
});

Then all the test cases can be successful. But i still get an ERROR:

Could not find a declaration file for module 'jest-canvas-mock/lib/mock/prototype'

• So My question is:

Is there a better way for us to use jest-canvas-mock with jest.resetAllMocks() ?

Thanks!

[ducna-lts]

Have you found any solution yet, I have the same problem, don't know how to setup mock before start.

[qiuhanWEI]

Have you found any solution yet, I have the same problem, don't know how to setup mock before start.

Not yet. @ducna-lts
I have to use the hack way import canvasMock from 'jest-canvas-mock/lib/mock/prototype';
and invoke canvasMock in beforeEach.

[akphi]

Another way is to create a setup file

// mockCanvas.js
import canvasMock from 'jest-canvas-mock/lib/mock/prototype.js';

beforeEach(() => {
  canvasMock();
});

and add that as a setup file in Jest config

setupFilesAfterEnv: [
     'mockCanvas.js'
    ],

[pbomb]

@hustcc @nicks I'm running into this issue as well and see that it seems to have been resolved by #98 several months back. Any chance y'all could make another release to get this fix out? It's even more needed since Jest changed the behavior of the restoreMocks configuration that now removes the implementation of jest.fn() mocks after each test.

[pbomb]

@hustcc @nicks bumping to see if it might be possible to publish another version of this library. Thanks!

[nicks]

@pbomb i don't have any special publishing powers on this repo. if it helps, my team used yarn patch to downstream it into our repo without waiting on a release.

[hustcc]

• jest-canvas-mock@2.5.0 https://github.com/hustcc/jest-canvas-mock/releases/tag/v2.5.0