@stdlib/assert/is-read-only-property/README.md

Standard assertion utilities.

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# isReadOnlyProperty

> Test if an object's own property is [read-only][@stdlib/utils/define-read-only-property].

<section class="usage">

## Usage

```javascript
var isReadOnlyProperty = require( '@stdlib/assert/is-read-only-property' );
```

#### isReadOnlyProperty( value, property )

Returns a `boolean` indicating if a `value` has a [read-only][@stdlib/utils/define-read-only-property] `property`.

<!-- eslint-disable no-restricted-syntax -->

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

var obj = {
    'foo': 'bar'
};

defineProperty( obj, 'beep', {
    'configurable': false,
    'enumerable': false,
    'writable': false,
    'value': 'boop'
});

defineProperty( obj, 'accessor', {
    'configurable': false,
    'enumerable': true,
    'get': function getter() {
        return obj.foo;
    }
});

var bool = isReadOnlyProperty( obj, 'foo' );
// returns false

bool = isReadOnlyProperty( obj, 'beep' );
// returns true

bool = isReadOnlyProperty( obj, 'accessor' );
// returns true
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   Value arguments other than `null` or `undefined` are coerced to `objects`.

    ```javascript
    var bool = isReadOnlyProperty( 'beep', 'length' );
    // returns true
    ```

-   Property arguments are coerced to `strings`.

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

    var obj = {};

    defineProperty( obj, 'null', {
        'configurable': false,
        'enumerable': true,
        'writable': false,
        'value': true
    });

    var bool = isReadOnlyProperty( obj, null );
    // returns true
    ```

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint-disable object-curly-newline -->

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

```javascript
var isReadOnlyProperty = require( '@stdlib/assert/is-read-only-property' );

var bool = isReadOnlyProperty( 'a', 'length' );
// returns true

bool = isReadOnlyProperty( { 'a': 'b' }, 'a' );
// returns false

bool = isReadOnlyProperty( [ 'a' ], 0 );
// returns false

bool = isReadOnlyProperty( { 'null': false }, null );
// returns false

bool = isReadOnlyProperty( { '[object Object]': false }, {} );
// returns false

bool = isReadOnlyProperty( {}, 'toString' );
// returns false

bool = isReadOnlyProperty( {}, 'hasOwnProperty' );
// returns false

bool = isReadOnlyProperty( null, 'a' );
// returns false

bool = isReadOnlyProperty( void 0, 'a' );
// returns false
```

</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/assert/is-read-only-property-in`][@stdlib/assert/is-read-only-property-in]</span><span class="delimiter">: </span><span class="description">test if an object's own or inherited property is read-only.</span>
-   <span class="package-name">[`@stdlib/assert/is-read-write-property`][@stdlib/assert/is-read-write-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is readable and writable.</span>
-   <span class="package-name">[`@stdlib/assert/is-readable-property`][@stdlib/assert/is-readable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is readable.</span>
-   <span class="package-name">[`@stdlib/assert/is-writable-property`][@stdlib/assert/is-writable-property]</span><span class="delimiter">: </span><span class="description">test if an object's own property is writable.</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">

[@stdlib/utils/define-read-only-property]: https://www.npmjs.com/package/@stdlib/utils-define-read-only-property

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

[@stdlib/assert/is-read-only-property-in]: https://github.com/stdlib-js/assert/tree/main/is-read-only-property-in

[@stdlib/assert/is-read-write-property]: https://github.com/stdlib-js/assert/tree/main/is-read-write-property

[@stdlib/assert/is-readable-property]: https://github.com/stdlib-js/assert/tree/main/is-readable-property

[@stdlib/assert/is-writable-property]: https://github.com/stdlib-js/assert/tree/main/is-writable-property

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

</section>

<!-- /.links -->