3.2 KiB
is-data-descriptor
Returns true if a value has the characteristics of a valid JavaScript data descriptor.
Install
Install with npm:
$ npm i is-data-descriptor --save
Usage
var isDataDesc = require('is-data-descriptor');
Examples
true
when the descriptor has valid properties with valid values.
// `value` can be anything
isDataDesc({value: 'foo'})
isDataDesc({value: function() {}})
isDataDesc({value: true})
//=> true
false
when not an object
isDataDesc('a')
//=> false
isDataDesc(null)
//=> false
isDataDesc([])
//=> false
false
when the object has invalid properties
isDataDesc({value: 'foo', bar: 'baz'})
//=> false
isDataDesc({value: 'foo', bar: 'baz'})
//=> false
isDataDesc({value: 'foo', get: function(){}})
//=> false
isDataDesc({get: function(){}, value: 'foo'})
//=> false
false
when a value is not the correct type
isDataDesc({value: 'foo', enumerable: 'foo'})
//=> false
isDataDesc({value: 'foo', configurable: 'foo'})
//=> false
isDataDesc({value: 'foo', writable: 'foo'})
//=> false
Valid properties
The only valid data descriptor properties are the following:
configurable
(required)enumerable
(required)value
(optional)writable
(optional)
To be a valid data descriptor, either value
or writable
must be defined.
Invalid properties
A descriptor may have additional invalid properties (an error will not be thrown).
var foo = {};
Object.defineProperty(foo, 'bar', {
enumerable: true,
whatever: 'blah', // invalid, but doesn't cause an error
get: function() {
return 'baz';
}
});
console.log(foo.bar);
//=> 'baz'
Related projects
- is-accessor-descriptor: Returns true if a value has the characteristics of a valid JavaScript accessor descriptor. | homepage
- is-descriptor: Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for… more | homepage
- isobject: Returns true if the value is an object and not an array or null. | homepage
Running tests
Install dev dependencies:
$ npm i -d && npm test
Contributing
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Author
Jon Schlinkert
License
Copyright © 2015 Jon Schlinkert Released under the MIT license.
This file was generated by verb on December 28, 2015.