has.js - mozsearch

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/* Any copyright is dedicated to the Public Domain.

 * http://creativecommons.org/licenses/publicdomain/ */

// Reflect.has is identical to the `in` operator.

assertEq(Reflect.has({x: 0}, "x"), true);

assertEq(Reflect.has({x: 0}, "y"), false);

assertEq(Reflect.has({x: 0}, "toString"), true);

// The target can be an array; Reflect.has works on array elements.

var arr = ["zero"];

arr[10000] = 0;

assertEq(Reflect.has(arr, "10000"), true);

assertEq(Reflect.has(arr, 10000), true);

assertEq(Reflect.has(arr, "-0"), false);

assertEq(Reflect.has(arr, -0), true);

// And string objects (though not string primitives; see target.js).

var str = new String("hello");

assertEq(Reflect.has(str, "4"), true);

assertEq(Reflect.has(str, "-0"), false);

assertEq(Reflect.has(str, -0), true);

// Proxy without .has() handler method

var obj = {get prop() {}};

for (var i = 0; i < 2; i++) {

    obj = new Proxy(obj, {});

    assertEq(Reflect.has(obj, "prop"), true);

    assertEq(Reflect.has(obj, "nope"), false);

// Proxy with .has() handler method

obj = new Proxy({}, {

    has(t, k) { return k.startsWith("door"); }

});

assertEq(Reflect.has(obj, "doorbell"), true);

assertEq(Reflect.has(obj, "dormitory"), false);

// For more Reflect.has tests, see target.js and propertyKeys.js.

reportCompare(0, 0);