Object-getOwnPropertyDescriptor-01.js

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// getOwnPropertyDescriptor works with simple data properties.

var g = newGlobal({newCompartment: true});

var dbg = Debugger(g);

var hits;

var expected;

dbg.onDebuggerStatement = function (frame) {

    var args = frame.arguments;

    var obj = args[0], id = args[1];

    var desc = obj.getOwnPropertyDescriptor(id);

    if (expected === undefined) {

        assertEq(desc, undefined);

    } else {

        assertEq(desc instanceof Object, true);

        assertEq(desc.enumerable, expected.enumerable);

        assertEq(desc.configurable, expected.configurable);

        assertEq(desc.hasOwnProperty("value"), true);

        assertEq(desc.value, expected.value);

        assertEq(desc.writable, expected.writable === undefined ? true : expected.writable);

        assertEq("get" in desc, false);

        assertEq("set" in desc, false);

    hits++;

};

g.eval("function f(obj, id) { debugger; }");

function test(obj, id, desc) {

    expected = desc;

    hits = 0;

    g.f(obj, id);

    assertEq(hits, 1);

var obj = g.eval("({a: 1, ' ': undefined, '0': 0})");

test(obj, "a", {value: 1, enumerable: true, configurable: true});

test(obj, " ", {value: undefined, enumerable: true, configurable: true});

test(obj, "b", undefined);

test(obj, "0", {value: 0, enumerable: true, configurable: true});

test(obj, 0, {value: 0, enumerable: true, configurable: true});

var arr = g.eval("[7,,]");

test(arr, 'length', {value: 2, enumerable: false, configurable: false});

test(arr, 0, {value: 7, enumerable: true, configurable: true});

test(arr, "0", {value: 7, enumerable: true, configurable: true});

test(arr, 1, undefined);

test(arr, "1", undefined);

test(arr, 2, undefined);

test(arr, "2", undefined);

test(arr, "argelfraster", undefined);

var re = g.eval("/erwe/");

test(re, 'lastIndex', {value: 0, enumerable: false, configurable: false});

// String objects have a well-behaved resolve hook.

var str = g.eval("new String('hello world')");

test(str, 'length', {value: 11, enumerable: false, configurable: false, writable: false});

test(str, 0, {value: 'h', enumerable: true, configurable: false, writable: false});

test(str, "0", {value: 'h', enumerable: true, configurable: false, writable: false});