@popovmp/mocha-tiny NPM

Mocha-tiny - straightforward unit testing: `describe` and `it`

mocha-tiny is a very simple, zero dependencies helper for unit tests.

Homepage: https://github.com/popovmp/mocha-tiny

Synopsis

const {strictEqual}  = require('assert')
const {describe, it} = require('@popovmp/mocha-tiny')

function sum(m, n) {
    return m + n
}

describe('Test math', () => {
    describe('sum(m, n)', () => {
        it('is a function', () => {
           strictEqual(typeof sum, 'function')
        })

        it('accepts two args', () => {
            strictEqual(sum.length, 2)
        })

        it('sums numbers', () => {
            const actual   = sum(2, 3)
            const expected = 5
            strictEqual(actual, expected)
        })
    })
})

Output - all passed:

mocha-tiny all passed

Output - a failed test:

mocha-tiny failed test

Installation

npm install @popovmp/mocha-tiny

Usage

mocha-tiny runs a test functions, collects stats, and prints a summary.

Usually you have one or two levels of nested describe function, which contains a number of it functions. The actual tests are in the second argument of it.

describe('system under test', () => {
    describe('method under test', () => {
        it('behavior', () => {
            const actual   = getFoo()
            const expected = 'foo'
            assert.strictEqual(actual, expected)
        });
    });
});

The helper runs the describe and the it functions sequentially. It means, you can initialize your tests at the begging of a describe block and to clean up at the end.

describe('Test group', () => {
    // Init the test environment.
    const systemUnderTest = {
        theAnswer: 42,
    }

    it('test...', () => {
       strictEqual(systemUnderTest.theAnswer, 42)
    })

    // Clean
    systemUnderTest.theAnswer = 0;
})

mocha-tiny throws an error if there are failed tests.

Run all tests

mocha-tiny exports a mocha-tiny command. It finds and runs all tests under the ./test folder and its sub-folders.

The accepted test files format is test-name.test.js.

You can set this command in your package.js:

{
  "scripts": {
    "test": "mocha-tiny"
  }
}

Methods

mocha-tiny exports two methods:

/**
 * Runs a group of tests
 *
 * @param { string   } message - description of the test group
 * @param { function } content - contains a `describe` or `it` functions
 */
function describe(message, content) { }

/**
 * Runs an assertion function
 *
 * @param { string   } message   - test description
 * @param { function } assertion - contains an assertion
 */
function it(message, assertion) { }