assert-kindof

Check native type of value and throw AssertionError if not okey. Clean stack traces. Simplicity. Built on is-kindof.

You might also be interested in kind-of-extra.

Highlights

• simplicity: pretty simple and stable codebase, built on kind-of and kind-of-extra
• flexibility: expose methods for each javascript type, using kind-of-types
• better coverage: ensures that your code will not have many branches
• clean stack traces: clean and small stack traces, using clean-stacktrace
• type checking: exposes is-kindof methods for returning booleans
• negations: support "not" modifier, e.g. is.not.array(val)
• errors: enhanced error objects with actual, expected, operator and value props
• messages: customizable and clean error messages

Table of Contents

• Install
• Usage
• API
  • .is
  • .array
  • .boolean
  • .buffer
  • .date
  • .error
  • .function
  • .generator
  • .generatorfunction
  • .map
  • .null
  • .number
  • .object
  • .promise
  • .regexp
  • .set
  • .stream
  • .string
  • .symbol
  • .undefined
  • .weakmap
  • .weakset
• Related
• Contributing
• Building docs
• Running tests
• Author
• License

(TOC generated by verb using markdown-toc)

Install

Install with npm

$ npm install assert-kindof --save

or install using yarn

$ yarn add assert-kindof

Usage

For more use-cases see the tests

1const assertKindof = require('assert-kindof')

API

.is

All methods from is-kindof are also exposed, so check its docs. That .is is object with methods with same names as in this package.

Example

1var assertKindof = require('assert-kindof')
2
3assertKindof.is.array(123) // => false
4assertKindof.is.array([11, 22, 33]) // => true
5
6assertKindof.array([11, 22, 33]) // => not throws
7
8try {
9  assertKindof.array(123) // => AssertionError: number !== array
10} catch (err) {
11  console.log(err.message) // => 'number !== array'
12}

.array

Check value is array, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.array([1, 2, 3]) // => not throws
3assert.array(123) // => AssertionError: number !== array
4
5try {
6  assert.array({ foo: 'bar' }, 'expect `val` to be {expected}')
7} catch (err) {
8  console.log(err.message) // => 'expect `val` to be array'
9  console.log(err.actual) // => object
10  console.log(err.expected) // => array
11  console.log(err.value) // => { foo: 'bar' }
12}

.boolean

Check value is boolean, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.boolean(true) // => not throws
3assert.boolean(false) // => not throws
4assert.boolean(123) // => AssertionError: number !== boolean
5assert.boolean(null) // => AssertionError: null !== boolean
6
7try {
8  assert.boolean([1, 2, 3], 'expect `val` to be {expected}')
9} catch (err) {
10  console.log(err.message) // => 'expect `val` to be boolean'
11  console.log(err.actual) // => array
12  console.log(err.expected) // => boolean
13  console.log(err.value) // => [1, 2, 3]
14}

.buffer

Check value is buffer, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.buffer(new Buffer('foo')) // => not throws
3assert.buffer(123) // => AssertionError: number !== buffer
4
5try {
6  assert.buffer(true, 'expect `val` to be {expected}')
7} catch (err) {
8  console.log(err.message) // => 'expect `val` to be buffer'
9  console.log(err.actual) // => boolean
10  console.log(err.expected) // => buffer
11  console.log(err.value) // => true
12}

.date

Check value is date, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.date(new Date()) // => not throws
3assert.date(123) // => AssertionError: number !== date
4
5try {
6  assert.date({ a: 'b' }, 'expect `val` to be {expected}')
7} catch (err) {
8  console.log(err.message) // => 'expect `val` to be date'
9  console.log(err.actual) // => object
10  console.log(err.expected) // => date
11  console.log(err.value) // => { a: 'b' }
12}

.error

Check value is error, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.error(new Error()) // => not throws
3assert.error(new TypeError()) // => not throws
4assert.error(123) // => AssertionError: number !== error
5
6try {
7  assert.error({ a: 'b' }, 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be error'
10  console.log(err.actual) // => object
11  console.log(err.expected) // => error
12  console.log(err.value) // => { a: 'b' }
13}

.function

Check value is function, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.function(function noop () {}) // => not throws
3assert.function((a, b) => {}) // => not throws
4assert.function(123) // => AssertionError: number !== error
5
6assert.function(function * noop () {})
7// => AssertionError: generatorfunction !== function
8
9try {
10  assert.function({ a: 'b' }, 'expect `val` to be {expected}')
11} catch (err) {
12  console.log(err.message) // => 'expect `val` to be function'
13  console.log(err.actual) // => object
14  console.log(err.expected) // => function
15  console.log(err.value) // => { a: 'b' }
16}

.generator

Check value is generator, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var generator = (function * gen () { yield 42 })()
2var genFn = function * genFn () {}
3var noop = () => { return 123 }
4
5assert.generator(generator) // => not throws
6assert.generator(genFn) // => AssertionError: generatorfunction !== generator
7assert.generator(noop) // => AssertionError: function !== generator
8assert.generator(123) // => AssertionError: number !== generator
9
10try {
11  assert.generator({ a: 'b' }, 'expect `val` to be {expected}')
12} catch (err) {
13  console.log(err.message) // => 'expect `val` to be generator'
14  console.log(err.actual) // => object
15  console.log(err.expected) // => generator
16  console.log(err.value) // => { a: 'b' }
17}

.generatorfunction

Check value is generator function, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var generator = (function * gen () { yield 42 })()
2var genFn = function * genFn () {}
3var noop = () => { return 123 }
4
5assert.generatorfunction(genFn) // => not throws
6
7assert.generatorfunction(generator) // => AssertionError: generator !== generatorfunction
8assert.generatorfunction(noop) // => AssertionError: function !== generatorfunction
9assert.generatorfunction(123) // => AssertionError: number !== generatorfunction
10
11try {
12  assert.generatorfunction({ a: 'b' }, 'expect `val` to be {expected}')
13} catch (err) {
14  console.log(err.message) // => 'expect `val` to be generatorfunction'
15  console.log(err.actual) // => object
16  console.log(err.expected) // => generatorfunction
17  console.log(err.value) // => { a: 'b' }
18}

.map

Check value is ES2015/ES6 Map, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.map(new Map()) // => not throws
3assert.map(new WeakMap()) // => AssertionError: weakmap !== map
4assert.map(123) // => AssertionError: number !== map
5
6try {
7  assert.map(123, 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be map'
10  console.log(err.actual) // => number
11  console.log(err.expected) // => map
12  console.log(err.value) // => { a: 'b' }
13}

.null

Check value is null, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.null(null) // => not throws
3assert.null({ a: 'b' }) // => AssertionError: object !== null
4assert.null(123) // => AssertionError: number !== null
5
6try {
7  assert.null(123, 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be null'
10  console.log(err.actual) // => number
11  console.log(err.expected) // => null
12  console.log(err.value) // => 123
13}

.number

Check value is number, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.number(123) // => not throws
3assert.number({ a: 'b' }) // => AssertionError: object !== number
4assert.number(null) // => AssertionError: null !== number
5
6try {
7  assert.number([111, 222], 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be number'
10  console.log(err.actual) // => array
11  console.log(err.expected) // => number
12  console.log(err.value) // => [111, 222]
13}

.object

Check value is object, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.object({ aaa: 'bbb' }) // => not throws
3assert.object([1, 2, 3]) // => AssertionError: array !== object
4assert.object(null) // => AssertionError: null !== object
5
6try {
7  assert.object([111, 222], 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be object'
10  console.log(err.actual) // => array
11  console.log(err.expected) // => object
12  console.log(err.value) // => [111, 222]
13}

.promise

Check value is promise, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.promise(Promise.resolve(123)) // => not throws
3assert.promise(Promise.reject(new Error('foo'))) // => not throws
4
5assert.promise(new Map()) // => AssertionError: map !== promise
6assert.promise(123) // => AssertionError: number !== promise
7
8try {
9  assert.promise({ a: 1 }, 'expect `val` to be {expected}')
10} catch (err) {
11  console.log(err.message) // => 'expect `val` to be promise'
12  console.log(err.actual) // => object
13  console.log(err.expected) // => promise
14  console.log(err.value) // => { a: 1 }
15}

.regexp

Check value is regexp, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.regexp(/foo ba?r abz/i) // => not throws
3assert.regexp(new RegExp('aa bb')) // => not throws
4
5assert.regexp(new Map()) // => AssertionError: map !== regexp
6assert.regexp(123) // => AssertionError: number !== regexp
7
8try {
9  assert.regexp({ a: 1 }, 'expect `val` to be {expected}')
10} catch (err) {
11  console.log(err.message) // => 'expect `val` to be regexp'
12  console.log(err.actual) // => object
13  console.log(err.expected) // => regexp
14  console.log(err.value) // => { a: 1 }
15}

.set

Check value is ES2015/ES6 Set, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.set(new Set()) // => not throws
3assert.set(new Map()) // => AssertionError: map !== set
4assert.set(123) // => AssertionError: number !== set
5
6try {
7  assert.set({ a: 1 }, 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be set'
10  console.log(err.actual) // => object
11  console.log(err.expected) // => set
12  console.log(err.value) // => { a: 1 }
13}

.stream

Check value is stream, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var through2 = require('through2')
2assert.stream(through2()) // => not throws
3assert.stream(through2.obj()) // => not throws
4
5assert.stream(new Map()) // => AssertionError: map !== stream
6assert.stream(123) // => AssertionError: number !== stream
7
8try {
9  assert.stream({ a: 1 }, 'expect `val` to be {expected}')
10} catch (err) {
11  console.log(err.message) // => 'expect `val` to be stream'
12  console.log(err.actual) // => object
13  console.log(err.expected) // => stream
14  console.log(err.value) // => { a: 1 }
15}

.string

Check value is string, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var fn = function aa () { return 123 }
2assert.string('foo bar baz') // => not throws
3assert.string(fn.toString()) // => not throws
4assert.string(new String('abc')) // => not throws
5
6assert.string(new Map()) // => AssertionError: map !== string
7assert.string(123) // => AssertionError: number !== string
8
9try {
10  assert.string({ a: 1 }, 'expect `val` to be {expected}')
11} catch (err) {
12  console.log(err.message) // => 'expect `val` to be string'
13  console.log(err.actual) // => object
14  console.log(err.expected) // => string
15  console.log(err.value) // => { a: 1 }
16}

.symbol

Check value is Symbol, if not throws AssertionError.

var assert = require('assert-kindof')*

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1assert.symbol(Symbol()) // => not throws
2
3assert.symbol(new Map()) // => AssertionError: map !== symbol
4assert.symbol(123) // => AssertionError: number !== symbol
5
6try {
7  assert.symbol({ a: 1 }, 'expect `val` to be {expected}')
8} catch (err) {
9  console.log(err.message) // => 'expect `val` to be symbol'
10  console.log(err.actual) // => object
11  console.log(err.expected) // => symbol
12  console.log(err.value) // => { a: 1 }
13}

.undefined

Check value is undefined, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.undefined() // => not throws
3assert.undefined(undefined) // => not throws
4
5assert.undefined(new Map()) // => AssertionError: map !== undefined
6assert.undefined(123) // => AssertionError: number !== undefined
7
8try {
9  assert.undefined({ a: 1 }, 'expect `val` to be {expected}')
10} catch (err) {
11  console.log(err.message) // => 'expect `val` to be undefined'
12  console.log(err.actual) // => object
13  console.log(err.expected) // => undefined
14  console.log(err.value) // => { a: 1 }
15}

.weakmap

Check value is ES2015/ES6 WeakMap, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.weakmap(new WeakMap()) // => not throws
3
4assert.weakmap(new WeakSet()) // => AssertionError: weakset !== weakmap
5assert.weakmap(new Map()) // => AssertionError: map !== weakmap
6assert.weakmap(123) // => AssertionError: number !== weakmap
7
8try {
9  assert.weakmap({ a: 1 }, 'expect `val` to be {expected}')
10} catch (err) {
11  console.log(err.message) // => 'expect `val` to be weakmap'
12  console.log(err.actual) // => object
13  console.log(err.expected) // => weakmap
14  console.log(err.value) // => { a: 1 }
15}

.weakset

Check value is ES2015/ES6 WeakSet, if not throws AssertionError.

Params

• value {any}: value to be checked
• message {String|Function}: error message; if function gets fn(actual, expected, value) signature
• returns {Undefined}: nothing is returned, throws if not okey

Example

1var assert = require('assert-kindof')
2assert.weakmap(new WeakSet()) // => not throws
3
4assert.weakset(new WeakMap()) // => AssertionError: weakmap !== weakset
5assert.weakset(new Map()) // => AssertionError: map !== weakset
6assert.weakset(123) // => AssertionError: number !== weakset
7
8try {
9  assert.weakset({ a: 1 }, 'expect `val` to be {expected}')
10} catch (err) {
11  console.log(err.message) // => 'expect `val` to be weakset'
12  console.log(err.actual) // => object
13  console.log(err.expected) // => weakset
14  console.log(err.value) // => { a: 1 }
15}

Related

• always-done: Handle completion and errors with elegance! Support for streams, callbacks, promises, child processes, async/await and sync functions. A drop-in replacement… more | homepage
• assertit: Thin sugar layer on top of testit framework, is-kindof and assert. | homepage
• is-kindof: Check type of given javascript value. Support promises, generators, streams, and native types. Built on kind-of lib. | homepage
• kind-of-extra: Additional functionality to kind-of type check utility. Support promises, generators, streams, errors. | homepage
• kind-of-types: List of all javascript types. Used and useful for checking, validation, sanitizing and testing. Like isStream, isPromise, isWeakset and etc. | homepage
• kind-of: Get the native type of a value. | homepage
• mukla: Small, parallel and fast test framework with suppport for async/await, promises, callbacks, streams and observables. Targets and works at node.js… more | homepage
• try-catch-callback: try/catch block with a callback, used in try-catch-core. Use it when you don't care about asyncness so much and don't… more | homepage
• try-catch-core: Low-level package to handle completion and errors of sync or asynchronous functions, using once and dezalgo libs. Useful for and… more | homepage
• try-read-json: Graceful reading of JSON value, using JSON.parse with support for optional callback | homepage

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Please read the contributing guidelines for advice on opening issues, pull requests, and coding standards.
If you need some help and can spent some cash, feel free to contact me at CodeMentor.io too.

In short: If you want to contribute to that project, please follow these things

1. Please DO NOT edit README.md, CHANGELOG.md and .verb.md files. See "Building docs" section.
2. Ensure anything is okey by installing the dependencies and run the tests. See "Running tests" section.
3. Always use npm run commit to commit changes instead of git commit, because it is interactive and user-friendly. It uses commitizen behind the scenes, which follows Conventional Changelog idealogy.
4. Do NOT bump the version in package.json. For that we use npm run release, which is standard-version and follows Conventional Changelog idealogy.

Thanks a lot! :)

Building docs

Documentation and that readme is generated using verb-generate-readme, which is a verb generator, so you need to install both of them and then run verb command like that

$ npm install verbose/verb#dev verb-generate-readme --global && verb

Please don't edit the README directly. Any changes to the readme must be made in .verb.md.

Running tests

Clone repository and run the following in that cloned directory

$ npm install && npm test

Author

Charlike Mike Reagent

• github/tunnckoCore
• twitter/tunnckoCore
• codementor/tunnckoCore

License

Copyright © 2015, 2017, Charlike Mike Reagent. Released under the MIT License.

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This file was generated by verb-generate-readme, v0.4.3, on March 10, 2017.
Project scaffolded using charlike cli.