mirror of
https://github.com/actions/setup-python
synced 2024-11-30 21:22:28 +08:00
193 lines
5.7 KiB
Markdown
193 lines
5.7 KiB
Markdown
# is-descriptor [](https://www.npmjs.com/package/is-descriptor) [](https://npmjs.org/package/is-descriptor) [](https://npmjs.org/package/is-descriptor) [](https://travis-ci.org/jonschlinkert/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](https://www.npmjs.com/):
|
|
|
|
```sh
|
|
$ npm install --save is-descriptor
|
|
```
|
|
|
|
## Usage
|
|
|
|
```js
|
|
var isDescriptor = require('is-descriptor');
|
|
|
|
isDescriptor({value: 'foo'})
|
|
//=> true
|
|
isDescriptor({get: function(){}, set: function(){}})
|
|
//=> true
|
|
isDescriptor({get: 'foo', set: function(){}})
|
|
//=> false
|
|
```
|
|
|
|
You may also check for a descriptor by passing an object as the first argument and property name (`string`) as the second argument.
|
|
|
|
```js
|
|
var obj = {};
|
|
obj.foo = 'abc';
|
|
|
|
Object.defineProperty(obj, 'bar', {
|
|
value: 'xyz'
|
|
});
|
|
|
|
isDescriptor(obj, 'foo');
|
|
//=> true
|
|
isDescriptor(obj, 'bar');
|
|
//=> true
|
|
```
|
|
|
|
## Examples
|
|
|
|
### value type
|
|
|
|
`false` when not an object
|
|
|
|
```js
|
|
isDescriptor('a');
|
|
//=> false
|
|
isDescriptor(null);
|
|
//=> false
|
|
isDescriptor([]);
|
|
//=> false
|
|
```
|
|
|
|
### data descriptor
|
|
|
|
`true` when the object has valid properties with valid values.
|
|
|
|
```js
|
|
isDescriptor({value: 'foo'});
|
|
//=> true
|
|
isDescriptor({value: noop});
|
|
//=> true
|
|
```
|
|
|
|
`false` when the object has invalid properties
|
|
|
|
```js
|
|
isDescriptor({value: 'foo', bar: 'baz'});
|
|
//=> false
|
|
isDescriptor({value: 'foo', bar: 'baz'});
|
|
//=> false
|
|
isDescriptor({value: 'foo', get: noop});
|
|
//=> false
|
|
isDescriptor({get: noop, value: noop});
|
|
//=> false
|
|
```
|
|
|
|
`false` when a value is not the correct type
|
|
|
|
```js
|
|
isDescriptor({value: 'foo', enumerable: 'foo'});
|
|
//=> false
|
|
isDescriptor({value: 'foo', configurable: 'foo'});
|
|
//=> false
|
|
isDescriptor({value: 'foo', writable: 'foo'});
|
|
//=> false
|
|
```
|
|
|
|
### accessor descriptor
|
|
|
|
`true` when the object has valid properties with valid values.
|
|
|
|
```js
|
|
isDescriptor({get: noop, set: noop});
|
|
//=> true
|
|
isDescriptor({get: noop});
|
|
//=> true
|
|
isDescriptor({set: noop});
|
|
//=> true
|
|
```
|
|
|
|
`false` when the object has invalid properties
|
|
|
|
```js
|
|
isDescriptor({get: noop, set: noop, bar: 'baz'});
|
|
//=> false
|
|
isDescriptor({get: noop, writable: true});
|
|
//=> false
|
|
isDescriptor({get: noop, value: true});
|
|
//=> false
|
|
```
|
|
|
|
`false` when an accessor is not a function
|
|
|
|
```js
|
|
isDescriptor({get: noop, set: 'baz'});
|
|
//=> false
|
|
isDescriptor({get: 'foo', set: noop});
|
|
//=> false
|
|
isDescriptor({get: 'foo', bar: 'baz'});
|
|
//=> false
|
|
isDescriptor({get: 'foo', set: 'baz'});
|
|
//=> false
|
|
```
|
|
|
|
`false` when a value is not the correct type
|
|
|
|
```js
|
|
isDescriptor({get: noop, set: noop, enumerable: 'foo'});
|
|
//=> false
|
|
isDescriptor({set: noop, configurable: 'foo'});
|
|
//=> false
|
|
isDescriptor({get: noop, configurable: 'foo'});
|
|
//=> false
|
|
```
|
|
|
|
## About
|
|
|
|
### Related projects
|
|
|
|
* [is-accessor-descriptor](https://www.npmjs.com/package/is-accessor-descriptor): Returns true if a value has the characteristics of a valid JavaScript accessor descriptor. | [homepage](https://github.com/jonschlinkert/is-accessor-descriptor "Returns true if a value has the characteristics of a valid JavaScript accessor descriptor.")
|
|
* [is-data-descriptor](https://www.npmjs.com/package/is-data-descriptor): Returns true if a value has the characteristics of a valid JavaScript data descriptor. | [homepage](https://github.com/jonschlinkert/is-data-descriptor "Returns true if a value has the characteristics of a valid JavaScript data descriptor.")
|
|
* [is-descriptor](https://www.npmjs.com/package/is-descriptor): Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for… [more](https://github.com/jonschlinkert/is-descriptor) | [homepage](https://github.com/jonschlinkert/is-descriptor "Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for data descriptors and accessor descriptors.")
|
|
* [isobject](https://www.npmjs.com/package/isobject): Returns true if the value is an object and not an array or null. | [homepage](https://github.com/jonschlinkert/isobject "Returns true if the value is an object and not an array or null.")
|
|
|
|
### Contributing
|
|
|
|
Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
|
|
|
|
### Contributors
|
|
|
|
| **Commits** | **Contributor** |
|
|
| --- | --- |
|
|
| 24 | [jonschlinkert](https://github.com/jonschlinkert) |
|
|
| 1 | [doowb](https://github.com/doowb) |
|
|
| 1 | [wtgtybhertgeghgtwtg](https://github.com/wtgtybhertgeghgtwtg) |
|
|
|
|
### Building docs
|
|
|
|
_(This project's readme.md is generated by [verb](https://github.com/verbose/verb-generate-readme), please don't edit the readme directly. Any changes to the readme must be made in the [.verb.md](.verb.md) readme template.)_
|
|
|
|
To generate the readme, run the following command:
|
|
|
|
```sh
|
|
$ npm install -g verbose/verb#dev verb-generate-readme && 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:
|
|
|
|
```sh
|
|
$ npm install && npm test
|
|
```
|
|
|
|
### Author
|
|
|
|
**Jon Schlinkert**
|
|
|
|
* [github/jonschlinkert](https://github.com/jonschlinkert)
|
|
* [twitter/jonschlinkert](https://twitter.com/jonschlinkert)
|
|
|
|
### License
|
|
|
|
Copyright © 2017, [Jon Schlinkert](https://github.com/jonschlinkert).
|
|
Released under the [MIT License](LICENSE).
|
|
|
|
***
|
|
|
|
_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.6.0, on July 22, 2017._ |