is-descriptor
Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for data descriptors and accessor descriptors.
Install
Install with npm:
$ npm install --save is-descriptor
Usage
var isDescriptor = require('is-descriptor');
isDescriptor({value: 'foo'})
isDescriptor({get: function(){}, set: function(){}})
isDescriptor({get: 'foo', set: function(){}})
You may also check for a descriptor by passing an object as the first argument and property name (string
) as the second argument.
var obj = {};
obj.foo = 'abc';
Object.defineProperty(obj, 'bar', {
value: 'xyz'
});
isDescriptor(obj, 'foo');
isDescriptor(obj, 'bar');
Examples
value type
false
when not an object
isDescriptor('a');
isDescriptor(null);
isDescriptor([]);
data descriptor
true
when the object has valid properties with valid values.
isDescriptor({value: 'foo'});
isDescriptor({value: noop});
false
when the object has invalid properties
isDescriptor({value: 'foo', bar: 'baz'});
isDescriptor({value: 'foo', bar: 'baz'});
isDescriptor({value: 'foo', get: noop});
isDescriptor({get: noop, value: noop});
false
when a value is not the correct type
isDescriptor({value: 'foo', enumerable: 'foo'});
isDescriptor({value: 'foo', configurable: 'foo'});
isDescriptor({value: 'foo', writable: 'foo'});
accessor descriptor
true
when the object has valid properties with valid values.
isDescriptor({get: noop, set: noop});
isDescriptor({get: noop});
isDescriptor({set: noop});
false
when the object has invalid properties
isDescriptor({get: noop, set: noop, bar: 'baz'});
isDescriptor({get: noop, writable: true});
isDescriptor({get: noop, value: true});
false
when an accessor is not a function
isDescriptor({get: noop, set: 'baz'});
isDescriptor({get: 'foo', set: noop});
isDescriptor({get: 'foo', bar: 'baz'});
isDescriptor({get: 'foo', set: 'baz'});
false
when a value is not the correct type
isDescriptor({get: noop, set: noop, enumerable: 'foo'});
isDescriptor({set: noop, configurable: 'foo'});
isDescriptor({get: noop, configurable: 'foo'});
About
Related projects
Contributing
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Contributors
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
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
Author
Jon Schlinkert
License
Copyright © 2017, Jon Schlinkert.
Released under the MIT License.
This file was generated by verb-generate-readme, v0.6.0, on July 22, 2017.