Returns true if a value has the characteristics of a valid JavaScript data descriptor.
true
when the descriptor has valid properties with valid values.
false
when not an object or when the object has invalid properties.
var isDataDesc = require('@devtea2027/mollitia-at-numquam-necessitatibus');
var assert = require('assert');
assert.equal(true, isDataDesc({ value: 'foo' }));
assert.equal(true, isDataDesc({ value: function () {} }));
assert.equal(true, isDataDesc({ value: true }));
assert.equal(false, isDataDesc('a'));
assert.equal(false, isDataDesc(null));
assert.equal(false, isDataDesc([]));
assert.equal(false, isDataDesc({ value: 'foo', bar: 'baz' }));
assert.equal(false, isDataDesc({ value: 'foo', bar: 'baz' }));
assert.equal(false, isDataDesc({ value: 'foo', get: function () {} }));
assert.equal(false, isDataDesc({ get: function () {}, value: 'foo' }) );
assert.equal(false, isDataDesc({ value: 'foo', enumerable: 'foo' }));
assert.equal(false, isDataDesc({ value: 'foo', configurable: 'foo' }));
assert.equal(false, isDataDesc({ value: 'foo', writable: 'foo' }));
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() {
return 'baz';
}
});
assert.equal(foo.bar, 'baz');
- is-accessor-descriptor: Returns true if a value has the characteristics of a valid JavaScript accessor descriptor.
- is-descriptor: Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for… more
Simply clone the repo, npm install
, and run npm test