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Unable to require() to use with Jest

See original GitHub issue

TypeError: Cannot read property 'prototype' of undefined
      
      at ../../../../node_modules/c3/c3.js:2720:30
      at ../../../../node_modules/c3/c3.js:3263:3
      at Object.<anonymous>.CLASS.target (../../../../node_modules/c3/c3.js:2:82)
      at Object.<anonymous> (../../../../node_modules/c3/c3.js:5:2)

which is

        window.SVGPathElement.prototype.createSVGPathSegClosePath = function () {

I’m not quite sure where to report this. Jest, jsdom, here?

Issue Analytics

State:
Created 6 years ago
Reactions:6
Comments:13 (2 by maintainers)

Top GitHub Comments

26reactions

emrebsonmezcommented, Oct 5, 2017

@fernandes Got it. I played around with it a bit more and was able to run the snapshot tests by mocking c3:

// __mocks__/c3.js
module.exports = () => 'c3';

and then in the Jest config portion of my package.json:

"moduleNameMapper": {
  "c3": "<rootDir>/__mocks__/c3.js",
}

1reaction

kt3kcommented, Sep 21, 2017

@brandonros If you don’t need c3 functionality in your jest test cases, I think it’s ok to replace SVGPathElement with dummy object.

I was able to require c3.js in node environment by dummying window.SVGPathElement like the below:

var JSDOM = require('jsdom').JSDOM;
global.window = new JSDOM().window;
window.SVGPathElement = function () {};
console.log(require('c3')); // => no error!