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javascriptes6-modulescommonjs

Prevent CommonJS module imported into ES module from executing code

I am attempting to import a CommonJS module (KeyboardJS) into some tests I have written in an ES module.

Here is my test code to give you an idea:

import { JSDOM } from 'jsdom'
import assert from 'assert'
import keyboardjs from 'keyboardjs' // <-- this line throws an error

// create mocked window object
const window = new JSDOM().window
const document = window.document

// pass this to keyboardjs?
keyboardjs.watch(document)

And here is the error:

Error: Cannot find window functions addEventListener or attachEvent.
    at Keyboard.watch (./node_modules/keyboardjs/dist/keyboard.js:614:19)
    at Keyboard.setContext (./node_modules/keyboardjs/dist/keyboard.js:587:14)
    at new Keyboard (./node_modules/keyboardjs/dist/keyboard.js:439:12)
    at ./node_modules/keyboardjs/dist/keyboard.js:1076:18
    at ./node_modules/keyboardjs/dist/keyboard.js:2:83
    at Object.<anonymous> (./node_modules/keyboardjs/dist/keyboard.js:5:2)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
    at Module.load (internal/modules/cjs/loader.js:928:32)
    at Function.Module._load (internal/modules/cjs/loader.js:769:14)
    at ModuleWrap.<anonymous> (internal/modules/esm/translators.js:199:29)
    at ModuleJob.run (internal/modules/esm/module_job.js:152:23)
    at async Loader.import (internal/modules/esm/loader.js:166:24)
    at async formattedImport (./node_modules/mocha/lib/nodejs/esm-utils.js:7:14)
    at async Object.exports.requireOrImport (./node_modules/mocha/lib/nodejs/esm-utils.js:48:32)
    at async Object.exports.loadFilesAsync (./node_modules/mocha/lib/nodejs/esm-utils.js:88:20)
    at async singleRun (./node_modules/mocha/lib/cli/run-helpers.js:125:3)
    at async Object.exports.handler (./node_modules/mocha/lib/cli/run.js:374:5)

It appears that keyboardjs is attempting to access the window object while it is loaded, which of course can't work since I am loading it in some test code.

Is there some special way to import it without triggering this behavior?

Solution

  • I've updated KeyboardJS so it doesn't throw like this on initialization, which means your code should work now.

    That said I would recommend checking out my new library called Keystrokes. It's the successor to KeyboardJS and comes with easier to use and more modern interface.