assert-deep-strict-equal

_Asynchronous assert fails in Mocha that you can see and don't timeout_


The assertDeepStrictEqual() function checks that two values or serializable objects are identical. 
The optional callback supports asynchronous specification suites and doesn't timeout on assertion failures.

A) Setup

Install package for node:
``shell
$ npm install --save-dev assert-deep-strict-equal
`
Import into your Mocha spec file:
`javascript
import { assertDeepStrictEqual } from 'assert-deep-strict-equal';
`

B) Usage

`javascript
const actual = { ingredient: 'sugar', units: 'grams', amount: 100 };
const expected = { ingredient: 'sugar', units: 'grams', amount: 100 };
assertDeepStrictEqual(actual, expected, done);
`
The third parameter for the done callback is optional:
`javascript
assertDeepStrictEqual(actual, expected); //synchronous test case
`

C) Example

`javascript
describe('Star Wars API result for spaceship #3', () => {

it('is a Star Destroyer', (done) => {
const url = 'https://swapi.py4e.com/api/starships/3/';
const handleData = (data) => {
const actual = {
name: data.name,
model: data.model,
manufacturer: data.manufacturer,
};
const expected = {
name: 'Star Destroyer',
model: 'Imperial I-class Star Destroyer',
manufacturer: 'Kuat Drive Yards',
};
assertDeepStrictEqual(actual, expected, done);
};
fetchJson.get(url, { format: 'json' }).then(handleData);
});

});
`
Commands to run the above Star Destroyer example and others in examples.spec.js:
`shell
$ cd assert-deep-strict-equal
$ npm install
$ npm run examples
`
width=800 alt=screenshot>
Note that the assertion failure does _not_ cause a timeout and the test case error is easy to see and interpret. 
The value of the name field is "BOGUS!" (red), but it was expected to be "payapa-berry"` (green).

---
MIT License