Checks a given object against a given set of specifications to keep you from writing boilerplate tests.
const test = require('node:test')
// or: const test = require('tape')
// or: const test = require('tap')
const spok = require('spok')
// this would be returned from a function you are testing
const object = {
one : 1
, two : 2
, three : 3
, four : 4
, helloWorld : 'hello world'
, anyNum : 999
, anotherNum : 888
, anArray : [ 1, 2 ]
, anotherArray : [ 1, 2, 3 ]
, anObject : {}
}
// custom specification
function hasThreeElements(a) {
return a.length === 3
}
test('my object meets the specifications', (t) => {
spok(t, object, {
$topic : 'spok-example'
, one : spok.ge(1)
, two : 2
, three : spok.range(2, 4)
, four : spok.lt(5)
, helloWorld : spok.startsWith('hello')
, anyNum : spok.type('number')
, anotherNum : spok.number
, anArray : spok.array
, anotherArray : hasThreeElements
, anObject : spok.ne(undefined)
})
})
npm install spok
Since Node.js 16.x it includes a built-in test runner.
Spok support this out of the box as follows:
- it uses the build-in
assert
module to assert the values - it uses the passed
t: TestContext
to print diagnostic messages that detail the assertions mad
See ./example/node-test.js and ./example/node-test-nested.jsfor a full examples.
spok detects if colors should be used in the output in order to avoid breaking TAP compatibility when needed as follows:
- if
FORCE_COLOR
env var is set to1|true
colors are ALWAYS - if
NO_COLOR
env var is set to1|true
colors are NEVER used - if tests are executed via
node --test mytest.js
andFORCE_COLOR
is not set then colorse are disabled - if tests are executed via
node mytest.js
andNO_COLOR
is not set then colors are enabled
- tap and tape provide a
t
which mirrors theassert
module and also prints results and the diagnostics message to the console, thus spok usest
to perform assertions
See ./example/tape.js and ./example/tape-nested.jsfor a full examples.
Spok can be used out of the box with expect
, for instance when running tests with
cypress.io.
Simply create a custom assert function and pass it to spok. The main difference to running
tests with tape
is that if a single property in the compared object doesn't match the test
fails immediately.
import spok from 'spok'
const t = spok.adapters.chaiExpect(expect)
spok(t, meta, {
err: null,
fee: 5000,
status: {
Ok: null,
},
})
spok(t, meta, {
err: null,
fee: 4000,
status: {
Ok: null,
},
})
deepEqual
works great for most cases, but in some cases you need more control, i.e.
- values don't exactly match, but are in a given range
- you want to provide a predicate to determine if a value is correct or not
- you only want to check a subset of values contained in the object
By default spok prints the specification that a particular assertion satisified, i.e. satisfies: spok.range(2, 4)
.
You can turn that off via spok.printSpec = false
.
On the other hand if you want more details about the satisified spec do spok.printDescription = true
instead to get
spok to print things like satisfies: spok.range(2, 4) 2 <= value <= 4
.
Specs and descriptions are printed in gray so you can focus on the actual values of the test output.
Table of Contents generated with DocToc
spok provides a few common specification functions. However you can write your own functions as well, just return true
if specification was satisfied and false
if not (see example above).
If you write a specification function that would be useful to others please add it along with a test and provide a PR.
spok.*
comparison function names are derived from bash comparison
operators to make them easier to remember.
Checks the given specifications against the object.
When the tests are run the actual values are printed to verify visually while each provided specification is validated and a test failure caused if one of them fails.
Parameters
t
Object which has assertion functionsequal
anddeepEqual
(to compare objects) - use tap, tape, assert, Node.js TestContext or any other library that has those and thus is compatibleobj
Object the object to verify the specifications againstspecifications
Object the specifications to verify
Version of spok
that is less strict about the relation of the
specification type, namely it allows overriding the type manually or
derives it from the supplied parameter.
Use ONLY when you cannot adjust the types, so plain spok
works.
Specififies that the given number is within the given range, i.e. min<= x <=max
.
var spec = {
x: spok.range(1, 2) // specifies that x should be >=1 and <=2
}
Parameters
Specififies that a number is greater than the given criteria.
var spec = {
x: spok.gt(1) // specifies that x should be >1
}
Parameters
n
Number criteria
Specififies that a number is greater or equal the given criteria.
var spec = {
x: spok.ge(1) // specifies that x should be >=1
}
Parameters
n
Number criteria
Specififies that a number is less than the given criteria.
var spec = {
x: spok.lt(1) // specifies that x should be < 1
}
Parameters
n
Number criteria
Specififies that a number is less or equal the given criteria.
var spec = {
x: spok.le(1) // specifies that x should be <=1
}
Parameters
n
Number criteria
Specifies that the value is not equal another.
var spec = {
x: spok.ne(undefined) // specifies that x should be defined
}
Parameters
value
Any criteria
Specifies that the value is greater than zero
var spec = {
x: spok.gtz
}
Specifies that the value is greater or equal zero
var spec = {
x: spok.gez
}
Specifies that the value is less than zero
var spec = {
x: spok.ltz
}
Specifies that the value is less or equal zero
var spec = {
x: spok.lez
}
Specifies that the input is of a given type.
var spec = {
x: spok.type('number') // specifies that x should be a Number
}
Parameters
t
String expected type
Specifies that the input is an array.
var spec = {
x: spok.array // specifies that x should be an Array
}
Specifies that the input is an array with a specific number of elements
var spec = { x: spok.arrayElements(2) // specifies that x should be an Array with 2 elements }
Parameters
n
Number number of elements
Specifies that the input is an array with a number of elements in a given range
var spec = { x: spok.arrayElementsRange(2, 4) // specifies that x should be an Array with 2-4 elements }
Parameters
Specifies that the input of type number and isNaN(x)
returns false
.
var spec = {
x: spok.number // specifies that x should be a Number
}
Specifies that the input is a string.
var spec = {
x: spok.string // specifies that x should be a String
}
Specifies that the input is a function.
var spec = {
x: spok.function // specifies that x should be a function
}
Specifies that the input is an object and it is not null
.
var spec = {
x: spok.definedObject // specifies that x is a non-null object
}
Specifies that the string starts with the specified substring.
NOTE: only available with node.js which has an ES6 startsWith
function
var spec = {
x: spok.startsWith('hello') // specifies that x should start with 'hello'
}
Parameters
what
String substring the given string should start with
Specifies that the string ends with the specified substring.
NOTE: only available with node.js which has an ES6 endsWith
function
var spec = {
x: spok.endsWith('hello') // specifies that x should start with 'hello'
}
Parameters
what
String substring the given string should start with
Specifies that the string needs to match the given regular expression.
var spec = {
x: spok.test(/hello$/) // specifies that x should match /hello$/
}
Parameters
regex
RegExp regular expression against which the string is checked viatest
Specifies that a value is defined, i.e. it is neither null
nor undefined
.
var spec = {
x: spok.defined
}
Specifies that a value is notDefined, i.e. it is either null
or notDefined
.
var spec = {
x: spok.notDefined
}
MIT