@stdlib/utils/inherited-property-descriptor/README.md

Standard utilities.

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# inheritedPropertyDescriptor

> Return a property descriptor for an object's inherited property.

<section class="usage">

## Usage

<!-- eslint-disable id-length -->

```javascript
var inheritedPropertyDescriptor = require( '@stdlib/utils/inherited-property-descriptor' );
```

#### inheritedPropertyDescriptor( obj, property\[, level] )

Returns a property descriptor for an object's inherited property.

<!-- eslint-disable id-length -->

```javascript
function Foo() {
    return this;
}

Foo.prototype.bar = 'foo';

var obj = new Foo();

var desc = inheritedPropertyDescriptor( obj, 'bar' );
// returns {'configurable':true,'enumerable':true,'writable':true,'value':'foo'}
```

By default, the function walks an object's entire prototype chain. To limit the inheritance level, provide a `level` argument.

<!-- eslint-disable id-length -->

```javascript
var inherit = require( '@stdlib/utils/inherit' );

function Bar() {
    return this;
}

Bar.prototype.beep = 'boop';

function Foo() {
    Bar.call( this );
    return this;
}

inherit( Foo, Bar );

var f = new Foo();
var desc = inheritedPropertyDescriptor( f, 'beep', 1 );
// returns null
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   This function differs from the built-in `Object.getOwnPropertyDescriptor()` as follows:

    -   If provided `null` or `undefined`, the function returns `null`, rather than throwing an error.
    -   If an object does not have a provided inherited property, the function returns `null`, rather than `undefined`.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint-disable id-length -->

<!-- eslint no-undef: "error" -->

```javascript
var defineProperty = require( '@stdlib/utils/define-property' );
var inheritedPropertyDescriptor = require( '@stdlib/utils/inherited-property-descriptor' );

function Foo() {
    this.beep = 'boop';
    this.a = {
        'b': 'c'
    };
    defineProperty( this, 'baz', {
        'value': 'qux',
        'configurable': true,
        'writable': true,
        'enumerable': false
    });
    return this;
}

Foo.prototype.foo = [ 'bar' ];

var obj = new Foo();
var desc = inheritedPropertyDescriptor( obj, 'foo' );

console.log( desc );
// => {'configurable':true,'enumerable':true,'writable':true,'value':['bar']}
```

</section>

<!-- /.examples -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/utils/property-descriptor`][@stdlib/utils/property-descriptor]</span><span class="delimiter">: </span><span class="description">return a property descriptor for an object's own property.</span>
-   <span class="package-name">[`@stdlib/utils/property-descriptor-in`][@stdlib/utils/property-descriptor-in]</span><span class="delimiter">: </span><span class="description">return a property descriptor for an object's own or inherited property.</span>
-   <span class="package-name">[`@stdlib/utils/inherited-keys`][@stdlib/utils/inherited-keys]</span><span class="delimiter">: </span><span class="description">return an array of an object's inherited enumerable property names.</span>
-   <span class="package-name">[`@stdlib/utils/inherited-property-descriptors`][@stdlib/utils/inherited-property-descriptors]</span><span class="delimiter">: </span><span class="description">return an object's inherited property descriptors.</span>
-   <span class="package-name">[`@stdlib/utils/inherited-property-names`][@stdlib/utils/inherited-property-names]</span><span class="delimiter">: </span><span class="description">return an array of an object's inherited enumerable and non-enumerable property names.</span>
-   <span class="package-name">[`@stdlib/utils/inherited-property-symbols`][@stdlib/utils/inherited-property-symbols]</span><span class="delimiter">: </span><span class="description">return an array of an object's inherited symbol properties.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

<!-- <related-links> -->

[@stdlib/utils/property-descriptor]: https://github.com/stdlib-js/utils/tree/main/property-descriptor

[@stdlib/utils/property-descriptor-in]: https://github.com/stdlib-js/utils/tree/main/property-descriptor-in

[@stdlib/utils/inherited-keys]: https://github.com/stdlib-js/utils/tree/main/inherited-keys

[@stdlib/utils/inherited-property-descriptors]: https://github.com/stdlib-js/utils/tree/main/inherited-property-descriptors

[@stdlib/utils/inherited-property-names]: https://github.com/stdlib-js/utils/tree/main/inherited-property-names

[@stdlib/utils/inherited-property-symbols]: https://github.com/stdlib-js/utils/tree/main/inherited-property-symbols

<!-- </related-links> -->

</section>

<!-- /.links -->