ThunkTest

!Node.js CI

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

``javascript
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

`coffeescript
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.

`javascript
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.

`javascript
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')
// }
`

$3


`coffeescript
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
`bash
npm i thunk-test
`

browser script, global Test
`html

`

browser module
`javascript
import Test from 'https://unpkg.com/thunk-test/es.js'
``