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It seems no work when use mocha-jsdom when depend lib have 'window' variable.

See original GitHub issue

HI, I have a JS file import other libs which use the window variable and I want to test it by mocha.
I use ES6 and I must compile the test JS file by babel, I use the command mocha --compilers js:babel-core/register, but when I compile the JS there are some error as follow.
I use mocha-jsdom but it seems no work.
How I use mocha-jsdom to mock the ‘window’ variable? Thanks.

JS file something like this:

import xxx from 'xxx'; // use the 'window' variable

export default function foo() {
  xxx.bar(); 
}

test file something like this:

import jsdom from 'mocha-jsdom';
import foo from './foo';

describe('test' () => {
  jsdom();

  it(' test test', () => {
    foo();     
  });
});

error:

> mocha --compilers js:babel-core/register --recursive

.../node_modules/velocity-animate/velocity.js:403
})(window);
   ^

ReferenceError: window is not defined
    at Object.<anonymous> (...node_modules/velocity-animate/velocity.js:403:4)
    at Module._compile (module.js:425:26)
    at Module._extensions..js (module.js:432:10)
    at Object.require.extensions.(anonymous function) [as .js] (.../node_modules/babel-register/lib/node.js:138:7)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:313:12)
    at Module.require (module.js:366:17)
    at require (module.js:385:17)
    at Object.<anonymous> (.../node_modules/rc-collapse/lib/openAnimation.js:9:24)
    at Module._compile (module.js:425:26)
    at Module._extensions..js (module.js:432:10)
    at Object.require.extensions.(anonymous function) [as .js] (.../node_modules/babel-register/lib/node.js:138:7)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:313:12)
    at Module.require (module.js:366:17)
    at require (module.js:385:17)
    at Object.<anonymous> (.../node_modules/rc-collapse/lib/Collapse.js:17:22)
......

Issue Analytics

State:
Created 8 years ago
Comments:5 (1 by maintainers)

Top GitHub Comments

22reactions

EvHauscommented, Jul 31, 2019

For those running into the same problem, I found an alternate solution which seems to work better.

npm uninstall mocha-jsdom
npm install jsdom
Create a new setup.js file somewhere and put this code in it:

import jsdom from 'jsdom';

global.document = jsdom.jsdom('<!doctype html><html><body></body></html>');
global.window = document.defaultView;
global.navigator = global.window.navigator;

Load this file before all your mocha tests via mocha -r test/setup.js

Then you can import everything without issue and jsdom will be automatically loaded for all your tests.

1reaction

rstacruzcommented, Dec 18, 2015

You’ll need to import it inside a before() block.

var foo

describe('test', function () {
  jsdom()

  before(function () {
    foo = require('foo')
  })
})

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