Merge pull request #35 from jsertx/feat/is-undefined

feat: isUndefined

CHANGELOG

@@ -1,3 +1,6 @@
+#1.18.0
+- feat: isUndefined
+
 #1.17.0
 - feat: assignWith
 - feat: clone

README.md

@@ -28,6 +28,7 @@ Currently supported utils:
 - `isObjectLike` - Checks if passed `value` is object-like. A value is object-like if it's not `null`
 - `isPlainObject` - checks if input is object, not null object and not array object
 - `isString` - checks if input is a string
+- `isUndefined` - checks if an input is undefined
 - `mapKeys` - creates new object with the same values but with keys mapped by the provided function
 - `mapValues` - Maps the values of an object or array using the provided iteratee function or property path
 - `max` - computes the maximum value of array. If array is empty or falsey, undefined is returned

index.d.ts

@@ -24,6 +24,7 @@ export function isObject (verifiable: any): Boolean
 export function isObjectLike(value: any): boolean
 export function isPlainObject (val: any): boolean
 export function isString (val: any): boolean
+export function isUndefined (val: any): boolean
 export function mapKeys(obj: Object, mapper: (val: any, key: string) => string): Object
 export function mapValues(obj: Object, mapper: (val: any, key: string) => any): Object
 export function max (array: Array<any>): any

index.js

@@ -26,6 +26,7 @@ const isObject = require('./src/isObject')
 const isObjectLike = require('./src/isObjectLike')
 const isPlainObject = require('./src/isPlainObject')
 const isString = require('./src/isString')
+const isUndefined = require('./src/isUndefined')
 const mapKeys = require('./src/mapKeys')
 const mapValues = require('./src/mapValues')
 const max = require('./src/max')
@@ -75,6 +76,7 @@ module.exports = {
   isObjectLike,
   isPlainObject,
   isString,
+  isUndefined,
   mapKeys,
   mapValues,
   max,

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@bitfinexcom/lib-js-util-base",
-  "version": "1.17.0",
+  "version": "1.18.0",
   "description": "general utils",
   "main": "index.js",
   "scripts": {

src/isUndefined.js

@@ -0,0 +1,7 @@
+'use strict'
+
+const isUndefined = (val) => {
+  return val === undefined
+}
+
+module.exports = isUndefined

test/isUndefined.js

@@ -0,0 +1,39 @@
+'use strict'
+
+/* eslint-env mocha */
+const assert = require('assert')
+const isUndefined = require('../src/isUndefined')
+
+describe('isUndefined', () => {
+  it('should return true for undefined', () => {
+    assert.ok(isUndefined(undefined))
+  })
+
+  it('should return true for no param', () => {
+    assert.ok(isUndefined())
+  })
+
+  it('should return false for empty object', () => {
+    assert.equal(isUndefined({}), false)
+  })
+
+  it('should return false for empty array', () => {
+    assert.equal(isUndefined([]), false)
+  })
+
+  it('should return false for null', () => {
+    assert.equal(isUndefined(null), false)
+  })
+
+  it('should return false for false', () => {
+    assert.equal(isUndefined(false), false)
+  })
+
+  it('should return false for empty string', () => {
+    assert.equal(isUndefined(''), false)
+  })
+
+  it('should return false for zero', () => {
+    assert.equal(isUndefined(0), false)
+  })
+})