Unit Testing Functions

Unit testing in your app should be reserved for testing individual, standalone functions (i.e., "units" of code). To unit test a function, the test.load() method can be utilized:


import test from '@joystick.js/test';

test.that('add function adds two numbers together', async (assert = {}) => {
  const add = await test.load('lib/add.js', { default: true });
  assert.is(add(5, 5), 10);

Above, we've utilized the test.load() method to dynamically import a function we want to unit test in our app /lib/add.js. When we call test.load() a dynamic import of that path is performed. Because we expect /lib/add.js to export the add() function as a default export, we pass { default: true } as the second argument to test.load() to ensure that we're handed back the default export and not an object like { default: [Function add] }.

API Reference


Function API

Function API

test.load(path: string, options: object) => Promise;


  • path string Required

    The path relative to the root of your project that you want to load dynamically.

  • options object

    Options for test.load().

    • default boolean

      If set to true, tells test.load() that the file being loaded has a JavaScript export default statement and that the _default value on the returned object should be returned from test.load() (as opposed to the object with all of the file's exports).

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