Package Exports

thunk-test
thunk-test/index.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (thunk-test) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

ThunkTest

Modular testing for JavaScript. Declare tests as thunks, then execute them with a call.

const Test = require('thunk-test')

const identity = value => value

describe('identity', () => {
  it('returns whatever was passed to it',
    Test(identity)
      .case(+0, -0)
      .case('hey', 'hey')
      .case(NaN, result => {
        assert(isNaN(result))
      }))
})
//   identity
//  ✓ identity(1) -> 1
//  ✓ identity('hey') -> 'hey'
//  ✓ identity(NaN) |> result => assert(isNaN(result))
//     ✓ returns whatever was passed to it

thunk Tests are composed of a string descriptor, a function to test, and test cases denoted by .case and .throws. Any test cases may be asynchronous - either by returning a Promise explicitly or using the async keyword. Both .case and .throws accept a variadic number of arguments - the same as those provided to the function - with the exception of the last argument:

not a function - compare the return value directly by SameValueZero
an asserter function - pass the return value to the asserter function and let the asserter handle all the assertions. Note that if this value is a Promise, it is resolved before calling this function

Test(testname string, tester function)
  .case(...args, expectedResult any)
  .case(...args, asserter (result any)=>Promise|(disposer function)|null)
  .throws(...args, expectedError Error)
  .throws(...args, errorAsserter (error Error, result any)=>Promise|(disposer function)|null)

Concisely test many different cases with a declarative, idiomatic API.

Test(
  'pipe: awesome username generator',
  pipe([
    string => string.toUpperCase(),
    string => `x${string}x`,
    string => `X${string}X`,
    string => `x${string}x`,
    string => `_${string}_`,
  ]))
  .case('deimos', '_xXxDEIMOSxXx_') // objects deep equal, otherwise strict equal
  .case('|', result => assert.equal(result, '_xXx|xXx_')) // can supply a callback
  .case('?', async result => assert.equal(result, '_xXx?xXx_')) // async ok
  .throws(1, new TypeError('string.toUpperCase is not a function'))
  .throws(null, (err, arg0) => {
    assert.strictEqual(arg0, null)
    assert.strictEqual(err.name, 'TypeError')
    assert.strictEqual(err.message, 'Cannot read property \'toUpperCase\' of null')
  })()
// -- pipe: awesome username generator
//  ✓ pipeline('deimos') -> '_xXxDEIMOSxXx_'
//  ✓ pipeline('|') -> result => assert.equal(result, '_xXx|xXx_')
//  ✓ pipeline(1) throws TypeError: string.toUpperCase is not a function
//  ✓ pipeline(null) throws; (err, arg0) => {
//       assert.strictEqual(arg0, null)
//       assert.strictEqual(err.name, 'TypeError')
//       assert.strictEqual(err.message, 'Cannot read property \'toUpperCase\' of null')
//     }
//  ✓ pipeline('?') -> async result => assert.equal(result, '_xXx?xXx_')
//  ✓ pipeline(NaN) throws; async (err, arg0) => {
//       assert.strictEqual(arg0, NaN)
//       assert.strictEqual(err.name, 'TypeError')
//       assert.strictEqual(err.message, 'string.toUpperCase is not a function')
//     }

Preprocessing and postprocessing are available with callbacks supplied to .before and .after.

Note: since all callbacks are run with the same context, you can get and set values in the execution context (this) of a thunk Test from any provided callback.

Test('square', function square(number) {
  return number ** 2
}).before(function () {
    this.hello = 'world'
  })
  .case(3, function (squared) {
    assert(squared == 9)
    assert(this.hello == 'world')
  })
  .after(function () {
    assert(this.hello == 'world')
  })()
// -- square
// ✓ square(3) |> function (squared) {
//    assert(squared == 9)
//    assert(this.hello == 'world')
//  }

Syntax

ThunkTest = ()=>() {
  before: function=>this,
  after: function=>this,
  beforeEach: function=>this,
  afterEach: function=>this,
  case: (...args, expectedResult|function=>(disposer ()=>Promise<>|())|())=>this,
  throws: (...args, expectedError|function=>(disposer ()=>Promise<>|())|())=>this,
}

Test(story string, func function) -> ThunkTest

Test(func function) -> ThunkTest

Installation

with npm

npm i thunk-test

browser script, global Test

<script src="https://unpkg.com/thunk-test"></script>

browser module

import Test from 'https://unpkg.com/thunk-test/es.js'