class-utils

Utils for working with JavaScript classes and prototype methods.

Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your ❤️ and support.

Install

Install with npm:

$ npm install --save class-utils

Usage

var cu = require('class-utils');

API

.has

Returns true if an array has any of the given elements, or an object has any of the give keys.

Params

obj {Object}
val {String|Array}
returns {Boolean}

Example

cu.has(['a', 'b', 'c'], 'c');
//=> true

cu.has(['a', 'b', 'c'], ['c', 'z']);
//=> true

cu.has({a: 'b', c: 'd'}, ['c', 'z']);
//=> true

.hasAll

Returns true if an array or object has all of the given values.

Params

val {Object|Array}
values {String|Array}
returns {Boolean}

Example

cu.hasAll(['a', 'b', 'c'], 'c');
//=> true

cu.hasAll(['a', 'b', 'c'], ['c', 'z']);
//=> false

cu.hasAll({a: 'b', c: 'd'}, ['c', 'z']);
//=> false

.arrayify

Cast the given value to an array.

Params

val {String|Array}
returns {Array}

Example

cu.arrayify('foo');
//=> ['foo']

cu.arrayify(['foo']);
//=> ['foo']

.hasConstructor

Returns true if a value has a contructor

Params

value {Object}
returns {Boolean}

Example

cu.hasConstructor({});
//=> true

cu.hasConstructor(Object.create(null));
//=> false

.nativeKeys

Get the native ownPropertyNames from the constructor of the given object. An empty array is returned if the object does not have a constructor.

Params

obj {Object}: Object that has a constructor.
returns {Array}: Array of keys.

Example

cu.nativeKeys({a: 'b', b: 'c', c: 'd'})
//=> ['a', 'b', 'c']

cu.nativeKeys(function(){})
//=> ['length', 'caller']

.getDescriptor

Returns property descriptor key if it's an "own" property of the given object.

Params

obj {Object}
key {String}
returns {Object}: Returns descriptor key

Example

function App() {}
Object.defineProperty(App.prototype, 'count', {
  get: function() {
    return Object.keys(this).length;
  }
});
cu.getDescriptor(App.prototype, 'count');
// returns:
// {
//   get: [Function],
//   set: undefined,
//   enumerable: false,
//   configurable: false
// }

.copyDescriptor

Copy a descriptor from one object to another.

Params

receiver {Object}
provider {Object}
name {String}
returns {Object}

Example

function App() {}
Object.defineProperty(App.prototype, 'count', {
  get: function() {
    return Object.keys(this).length;
  }
});
var obj = {};
cu.copyDescriptor(obj, App.prototype, 'count');

.copy

Copy static properties, prototype properties, and descriptors from one object to another.

Params

receiver {Object}
provider {Object}
omit {String|Array}: One or more properties to omit
returns {Object}

.inherit

Inherit the static properties, prototype properties, and descriptors from of an object.

Params

receiver {Object}
provider {Object}
omit {String|Array}: One or more properties to omit
returns {Object}

.extend

Returns a function for extending the static properties, prototype properties, and descriptors from the Parent constructor onto Child constructors.

Params

Parent {Function}: Parent ctor
extend {Function}: Optional extend function to handle custom extensions. Useful when updating methods that require a specific prototype.
Child {Function}: Child ctor
proto {Object}: Optionally pass additional prototype properties to inherit.
returns {Object}

Example

var extend = cu.extend(Parent);
Parent.extend(Child);

// optional methods
Parent.extend(Child, {
  foo: function() {},
  bar: function() {}
});

.bubble

Bubble up events emitted from static methods on the Parent ctor.

Params

Parent {Object}
events {Array}: Event names to bubble up

About

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Running Tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

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

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