isDataPropertyIn

Test if an object's own or inherited property has a data descriptor.

Usage

var isDataPropertyIn = require( '@stdlib/assert/is-data-property-in' );

isDataPropertyIn( value, property )

Returns a boolean indicating if a value has a data property (either own or inherited).

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

var bool;
var obj;

function Foo() {
    this.foo = 'bar';
    return this;
}

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

defineProperty( Foo.prototype, 'accessor', {
    'configurable': false,
    'enumerable': false,
    'get': function getter() {
        return obj.foo;
    },
    'set': function setter( v ) {
        obj.foo = v;
    }
});

obj = new Foo();

bool = isDataPropertyIn( obj, 'foo' );
// returns true

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

bool = isDataPropertyIn( obj, 'accessor' );
// returns false

Notes

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

    var bool = isDataPropertyIn( 'beep', 'length' );
    // returns true
    
  • Non-symbol property arguments are coerced to strings.

    var obj = {
        'null': 'foo'
    };
    
    var bool = isDataPropertyIn( obj, null );
    // returns true
    

Examples

var isDataPropertyIn = require( '@stdlib/assert/is-data-property-in' );

var bool = isDataPropertyIn( [ 'a' ], 'length' );
// returns true

bool = isDataPropertyIn( { 'a': 'b' }, 'a' );
// returns true

bool = isDataPropertyIn( [ 'a' ], 0 );
// returns true

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

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

bool = isDataPropertyIn( {}, 'toString' );
// returns true

bool = isDataPropertyIn( {}, 'hasOwnProperty' );
// returns true

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

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