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// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Based on Mozilla Object.assign() tests
function checkDataProperty(object, propertyKey, value, writable, enumerable, configurable) {
var desc = Object.getOwnPropertyDescriptor(object, propertyKey);
assertFalse(desc === undefined);
assertTrue('value' in desc);
assertEquals(desc.value, value);
assertEquals(desc.writable, writable);
assertEquals(desc.enumerable, enumerable);
assertEquals(desc.configurable, configurable);
}
// 19.1.2.1 Object.assign ( target, ...sources )
assertEquals(Object.assign.length, 2);
// Basic functionality works with multiple sources
(function basicMultipleSources() {
var a = {};
var b = { bProp: 1 };
var c = { cProp: 2 };
Object.assign(a, b, c);
assertEquals(a, {
bProp: 1,
cProp: 2
});
})();
// Basic functionality works with symbols
(function basicSymbols() {
var a = {};
var b = { bProp: 1 };
var aSymbol = Symbol("aSymbol");
b[aSymbol] = 2;
Object.assign(a, b);
assertEquals(1, a.bProp);
assertEquals(2, a[aSymbol]);
})();
// Dies if target is null or undefined
assertThrows(function() { return Object.assign(null, null); }, TypeError);
assertThrows(function() { return Object.assign(null, {}); }, TypeError);
assertThrows(function() { return Object.assign(undefined); }, TypeError);
assertThrows(function() { return Object.assign(); }, TypeError);
// Calls ToObject for target
assertTrue(Object.assign(true, {}) instanceof Boolean);
assertTrue(Object.assign(1, {}) instanceof Number);
assertTrue(Object.assign("string", {}) instanceof String);
var o = {};
assertSame(Object.assign(o, {}), o);
// Only [[Enumerable]] properties are assigned to target
(function onlyEnumerablePropertiesAssigned() {
var source = Object.defineProperties({}, {
a: {value: 1, enumerable: true},
b: {value: 2, enumerable: false},
});
var target = Object.assign({}, source);
assertTrue("a" in target);
assertFalse("b" in target);
})();
// Properties are retrieved through Get()
// Properties are assigned through Put()
(function testPropertiesAssignedThroughPut() {
var setterCalled = false;
Object.assign({set a(v) { setterCalled = v }}, {a: true});
assertTrue(setterCalled);
})();
// Properties are retrieved through Get()
// Properties are assigned through Put(): Existing property attributes are not altered
(function propertiesAssignedExistingNotAltered() {
var source = {a: 1, b: 2, c: 3};
var target = {a: 0, b: 0, c: 0};
Object.defineProperty(target, "a", {enumerable: false});
Object.defineProperty(target, "b", {configurable: false});
Object.defineProperty(target, "c", {enumerable: false, configurable: false});
Object.assign(target, source);
checkDataProperty(target, "a", 1, true, false, true);
checkDataProperty(target, "b", 2, true, true, false);
checkDataProperty(target, "c", 3, true, false, false);
})();
// Properties are retrieved through Get()
// Properties are assigned through Put(): Throws TypeError if non-writable
(function propertiesAssignedTypeErrorNonWritable() {
var source = {a: 1};
var target = {a: 0};
Object.defineProperty(target, "a", {writable: false});
assertThrows(function() { return Object.assign(target, source); }, TypeError);
checkDataProperty(target, "a", 0, false, true, true);
})();
// Properties are retrieved through Get()
// Put() creates standard properties; Property attributes from source are
// ignored
(function createsStandardProperties() {
var source = {a: 1, b: 2, c: 3, get d() { return 4 }};
Object.defineProperty(source, "b", {writable: false});
Object.defineProperty(source, "c", {configurable: false});
var target = Object.assign({}, source);
checkDataProperty(target, "a", 1, true, true, true);
checkDataProperty(target, "b", 2, true, true, true);
checkDataProperty(target, "c", 3, true, true, true);
checkDataProperty(target, "d", 4, true, true, true);
})();
// Properties created during traversal are not copied
(function propertiesCreatedDuringTraversalNotCopied() {
var source = {get a() { this.b = 2 }};
var target = Object.assign({}, source);
assertTrue("a" in target);
assertFalse("b" in target);
})();
// String and Symbol valued properties are copied
(function testStringAndSymbolPropertiesCopied() {
var keyA = "str-prop";
var source = {"str-prop": 1};
var target = Object.assign({}, source);
checkDataProperty(target, keyA, 1, true, true, true);
})();
(function testExceptionsStopFirstException() {
var ErrorA = function ErrorA() {};
var ErrorB = function ErrorB() {};
var log = "";
var source = { b: 1, a: 1 };
var target = {
set a(v) { log += "a"; throw new ErrorA },
set b(v) { log += "b"; throw new ErrorB },
};
assertThrows(function() { return Object.assign(target, source); }, ErrorB);
assertEquals(log, "b");
})();
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