TypeError: Cannot set property 'fillStyle' of null

[akshay-kochhar]

Getting this error for all the test cases when they try to mount the component using enzyme. It shows error corresponding to the import line "import Lottie from 'lottie-react-web';"

Error:- With :- import Lottie from 'lottie-react-web'; at ../../common/temp/node_modules/.office.pkgs.visualstudio.com/lottie-web/5.5.2/node_modules/lottie-web/build/player/lottie.js:4165:23 at ../../common/temp/node_modules/.office.pkgs.visualstudio.com/lottie-web/5.5.2/node_modules/lottie-web/build/player/lottie.js:4168:6 at ../../common/temp/node_modules/.office.pkgs.visualstudio.com/lottie-web/5.5.2/node_modules/lottie-web/build/player/lottie.js:4268:2 at ../../common/temp/node_modules/.office.pkgs.visualstudio.com/lottie-web/5.5.2/node_modules/lottie-web/build/player/lottie.js:7:26

[RonnyO]

Installing and setting up https://www.npmjs.com/package/jest-canvas-mock worked for me

[hutber]

Its a shame you can't easlier to use with create-react-app though

[koriner]

@hutber You can use it with CRA

I just added require('jest-canvas-mock'); to the top of my setupTests.js file :)

[ICeZer0]

Is there another fix for this? My test suite is AVA?

[ICeZer0]

For those of us not using jest, my fix was to install canvas and JSDOM then mock the canvas

[AshishKapoor]

Installing and setting up https://www.npmjs.com/package/jest-canvas-mock worked for me

Also

$ yarn install canvas

[nk250319]

@hutber You can use it with CRA

I just added require('jest-canvas-mock'); to the top of my setupTests.js file :)

This totally worked for me. Thanks!!

[mlenser]

A better way is to setup jest to handle this. jest.config.js:

module.exports = {
  setupFilesAfterEnv: ['jest-canvas-mock'],
};

[bidva]

I still have the issue my app is created by react-app-rewired I have installed and setup jest-canvas-mock on package.json also installed canvas

"jest": {
    "setupFiles": [
      "<rootDir>/src/setupTests.js",
      "jest-canvas-mock"
    ],
    "collectCoverageFrom": [
      "src/**/*.{js,jsx,ts,tsx}",
      "!src/**/*.d.ts"
    ]
  },

and then imported that top of my setupTests.js

import 'jest-canvas-mock';
import { configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';
configure({ adapter: new Adapter() });

// Included to mock local storage in JS tests, see docs at
// https://www.npmjs.com/package/jest-localstorage-mock#in-create-react-app

require('jest-localstorage-mock');
// for plotly.js to work
//
window.URL.createObjectURL = function createObjectURL() {};
// to fix Error: Not implemented: HTMLCanvasElement.prototype.getContext
window.HTMLCanvasElement.prototype.getContext = () => {}; 

but still getting:

TypeError: Cannot set property 'fillStyle' of undefined

    > 1 | import { Player } from '@lottiefiles/react-lottie-player';
        | ^
      2 | import projection_replay from '../assets/lottie/projection_replay.json';
      3 |
      4 | const ProjectionNotReady = () => {

      at canvas (node_modules/@lottiefiles/react-lottie-player/node_modules/lottie-web/build/player/lottie.js:4699:9)
      at ImagePreloaderFactory (node_modules/@lottiefiles/react-lottie-player/node_modules/lottie-web/build/player/lottie.js:4701:12)
      at factory (node_modules/@lottiefiles/react-lottie-player/node_modules/lottie-web/build/player/lottie.js:4897:10)
      at lottie (node_modules/@lottiefiles/react-lottie-player/node_modules/lottie-web/build/player/lottie.js:7:26)
      at value (node_modules/@lottiefiles/react-lottie-player/node_modules/lottie-web/build/player/lottie.js:10:31)
      at value (node_modules/@lottiefiles/react-lottie-player/node_modules/tslib/tslib.es6.js:234:105)
      at Object.<anonymous> (node_modules/@lottiefiles/react-lottie-player/node_modules/tslib/tslib.es6.js:234:105)
      at Object.<anonymous> (src/components/ProjectionNotReady.js:1:1)
      at Object.<anonymous> (src/containers/Home/Models/Model.js:37:1)
      at Object.<anonymous> (src/containers/Home/Models/Models.js:27:1)
      at Object.<anonymous> (src/containers/Home/Home.js:10:1)
      at Object.<anonymous> (src/containers/Home/index.js:1:1)
      at Object.<anonymous> (src/containers/index.js:1:1)
      at Object.<anonymous> (src/Routes.jsx:4:1)
      at Object.<anonymous> (src/App.js:2:1)
      at Object.<anonymous> (src/App.test.js:3:1)

here is my component to test

import React from 'react';
import Routes from './Routes';
import { WithErrors } from './hocs/WithErrors';
import 'antd/dist/antd.css';
import './styles/styles.scss';

export const App = () => {
  return <Routes />;
};

export default WithErrors(App);

and here is my test

import React from 'react';
import renderer from 'react-test-renderer';
import App from './App';

describe('App', () => {
  test('Should render', () => {
    const tree = renderer.create(<App />).toJSON();
    expect(tree).toMatchSnapshot();
  });
});

any idea?

[bidva]

just for others, adding to import to existed setupTest.js didn't work for me but adding it to a new file worked. it's a bit strange but just said.

[MagnusHJensen]

Any updates on this?

doing the require('jest-canvas-mock'); at the top of setupTests.ts file worked fine, but It would be nice to not include a third-party lib just to use lottie.

[aquibbaig]

none of the above mentioned solutions work for me.

 TypeError: Cannot set properties of null (setting 'fillStyle')

      1 | import animationData from 'assets/lotties/paperplane.json';
      2 | import { useAuth } from 'hooks/useAuth';
    > 3 | import Lottie from 'lottie-react';

have installed jest-canvas-mock as devDep & have imported on top of setupTests.ts. i am using CRA with default react-scripts

[fahmij8]

This is my current solution. While I'm trying to import jest-canvas-mock in my setupTests file, I also do this in the error test file :

// Mock the CanvasRenderingContext2D object
class CanvasRenderingContext2DMock {
  fillStyle = '';
  fillRect = jest.fn();
  // Add any other necessary properties and methods
}

// Set up the mock before running the tests
beforeEach(() => {
  // @ts-ignore
  window.HTMLCanvasElement.prototype.getContext = () => {
    return new CanvasRenderingContext2DMock();
  };
});

// Now you can run your tests without encountering the error

[valdeirpsr]

For vitejs

1. Create file vitest.setup.ts

import { vi } from "vitest";

/* @ts-ignore */
HTMLCanvasElement.prototype.getContext = () => {
  return {
    fillStyle: '',
    fillRect: vi.fn()
  }
}

2. Add in your vitest.config.ts

export default defineConfig({
  test: {
    setupFiles: ['./vitest.setup.ts'],
  }
});

[kinoli]

This was needed for me in my vitest.setup.ts file.

/* @ts-ignore */
HTMLCanvasElement.prototype.getContext = () => {
  return {
    fillStyle: '',
    fillRect: vi.fn(),
    clearRect: vi.fn(),
    scale: vi.fn(),
  }
}

[htutwaiphyoe]

For vitejs

1. Create file vitest.setup.ts

import { vi } from "vitest";

/* @ts-ignore */
HTMLCanvasElement.prototype.getContext = () => {
  return {
    fillStyle: '',
    fillRect: vi.fn()
  }
}

2. Add in your vitest.config.ts

export default defineConfig({
  test: {
    setupFiles: ['./vitest.setup.ts'],
  }
});

Work for me, Thanks.