http-assert-plus

More assertions with status codes.

1import assert from 'http-assert-plus';
2// or
3const assert = require('http-assert-plus');
4
5const username = 'jdrydn';
6assert(username === 'not-jdrydn', 403, 'Authorization failed', {
7  code: 'NOT_AUTHORIZED',
8  username,
9});
10
11// Error: Authorization failed
12//     at http-assert-plus/README.md:22:1 {
13//   code: 'NOT_AUTHORIZED',
14//   statusCode: 403,
15//   status: 403,
16//   statusText: 'Forbidden',
17//   username: 'jdrydn'
18// }

Install

$ npm install --save http-assert-plus

API

This API matches the built-in assert module, and builds upon the success of http-assert, with a few differences:

• Each function throws an instance of Error when the assertion fails.
• Zero dependencies.

assert(value, [status], [message], [props])

Tests if value is truthy, and throws an Error if falsey.

assert.ok(value, [status], [message], [props])

Alias for above, tests if value is truthy, and throws an Error if falsey.

assert.fail([status], [message], [props])

Always throws an Error with the provided status/message/props.

assert.equal(a, b, [status], [message], [props])

Tests shallow, coercive equality between a & b using ==.

assert.notEqual(a, b, [status], [message], [props])

Tests shallow, coercive inequality between a & b using !=.

assert.strictEqual(a, b, [status], [message], [props])

Tests strict equality between a & b using ===.

assert.notStrictEqual(a, b, [status], [message], [props])

Tests strict inequality between a & b using !==.

assert.includes(a, b, [status], [message], [props])

Tests whether a includes b - where a has a method call includes.

assert.notIncludes(a, b, [status], [message], [props])

Tests whether a does not include b - where a has a method includes.

What about deep equality?

If you're looking for deep equality checks, check out deep-equal:

1import assert from 'http-assert-plus';
2import deepEqual from 'deep-equal';
3
4assert(deepEqual(a, b), 400, 'These two are not entirely equal');
5assert(deepEqual(a, b, { strict: true }), 400, 'These two are not entirely equal');
6// Error: Array does not strict-equal
7//     at http-assert-plus/README.md:72:1 {
8//   statusCode: 400,
9//   status: 400,
10//   statusText: 'Bad Request'
11// }

Browser supported?

Yes! Not all browsers support Error.captureStackTrace so this library checks if it is present in the current environment - if it isn't available the only behaviour you'll likely want to change is to pre-construct Error arguments to preserve a proper stack trace, like so:

1const { origin } = window.location;
2
3// In browsers, do this:
4assert(origin.startsWith('https://'), new Error('Expected origin to start with https://'), { origin });
5// Error: Expected origin to start with https://
6//     at http-assert-plus/README.md:99:39 {
7//   origin: 'http://localhost:4000',
8// }
9
10// Not this
11assert(origin.startsWith('https://'), 'Expected origin to start with https://');
12// Error: Expected origin to start with https://
13//     at node_modules/http-assert-plus/index.cjs:56:38 {
14//     at http-assert-plus/README.md:107:1 {
15//   origin: 'http://localhost:4000',
16// }

If you don't use a construct such as new Error, when reading stacktraces just ignore the first line as it'll always be the assert function :wink: