// Copyright 2019 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. // Flags: --harmony-private-methods "use strict"; // Basic private method test { let calledWith; class C { #a(arg) { calledWith = arg; } callA(arg) { this.#a(arg); } } const c = new C; assertEquals(undefined, c.a); assertEquals(undefined, calledWith); c.callA(1); assertEquals(1, calledWith); } // Call private method in another instance { class C { #a(arg) { this.calledWith = arg; } callAIn(obj, arg) { obj.#a(arg); } } const c = new C; const c2 = new C; assertEquals(undefined, c.a); assertEquals(undefined, c.calledWith); assertEquals(undefined, c2.calledWith); c2.callAIn(c, 'fromC2'); assertEquals('fromC2', c.calledWith); assertEquals(undefined, c2.calledWith); c2.callAIn(c2, 'c2'); assertEquals('fromC2', c.calledWith); assertEquals('c2', c2.calledWith); assertThrows(() => { c2.callAIn({}); }, TypeError); } // Private methods and private fields { class C { #a; constructor(a) { this.#a = a; } #getAPlus1() { return this.#a + 1; } equals(obj) { return this.#getAPlus1() === obj.#getAPlus1(); } } const c = new C(0); const c2 = new C(2); const c3 = new C(2); assertEquals(true, c2.equals(c3)); assertEquals(false, c2.equals(c)); assertEquals(false, c3.equals(c)); } // Class inheritance { class A { #val; constructor(a) { this.#val = a; } #a() { return this.#val; } getA() { return this.#a(); } } class B extends A { constructor(b) { super(b); } b() { return this.getA() } } const b = new B(1); assertEquals(1, b.b()); } // Private members should be accessed according to the class the // invoked method is in. { class A { #val; constructor(a) { this.#val = a; } #getVal() { return this.#val; } getA() { return this.#getVal(); } getVal() { return this.#getVal(); } } class B extends A { #val; constructor(a, b) { super(a); this.#val = b; } #getVal() { return this.#val; } getB() { return this.#getVal(); } getVal() { return this.#getVal(); } } const b = new B(1, 2); assertEquals(1, b.getA()); assertEquals(2, b.getB()); assertEquals(1, A.prototype.getVal.call(b)); assertEquals(2, B.prototype.getVal.call(b)); const a = new A(1); assertEquals(1, a.getA()); assertThrows(() => B.prototype.getB.call(a), TypeError); } // Private methods in nested classes. { class C { #b() { class B { #foo(arg) { return arg; } callFoo(arg) { return this.#foo(arg); } } return new B(); } createB() { return this.#b(); } } const c = new C; const b = c.createB(); assertEquals(1, b.callFoo(1)); } // Private methods in nested classes with inheritance. { class C { #b() { class B extends C { #foo(arg) { return arg; } callFoo(arg) { return this.#foo(arg); } } return new B(); } createB() { return this.#b(); } } const c = new C; const b = c.createB(); assertEquals(1, b.callFoo(1)); const b2 = b.createB(); assertEquals(1, b2.callFoo(1)); } // Class expressions. { const C = class { #a() { return 1; } callA(obj) { return obj.#a() } }; const c = new C; const c2 = new C; assertEquals(1, c.callA(c)); assertEquals(1, c.callA(c2)); } // Nested class expressions. { const C = class { #b() { const B = class { #foo(arg) { return arg; } callFoo(arg) { return this.#foo(arg); } }; return new B(); } createB() { return this.#b(); } }; const c = new C; const b = c.createB(); assertEquals(1, b.callFoo(1)); } // Nested class expressions with hierarchy. { const C = class { #b() { const B = class extends C { #foo(arg) { return arg; } callFoo(arg) { return this.#foo(arg); } } return new B(); } createB() { return this.#b(); } } const c = new C; const b = c.createB(); assertEquals(1, b.callFoo(1)); const b2 = b.createB(); assertEquals(1, b2.callFoo(1)); } // Adding the brand twice on the same object should throw. { class A { constructor(arg) { return arg; } } class C extends A { #x() { } constructor(arg) { super(arg); } } let c1 = new C({}); assertThrows(() => new C(c1), TypeError); } // Private methods should be not visible to proxies. { class X { #x() {} x() { this.#x(); }; callX(obj) { obj.#x(); } } let handlerCalled = false; const x = new X(); let p = new Proxy(new X, { apply(target, thisArg, argumentsList) { handlerCalled = true; Reflect.apply(target, thisArg, argumentsList); } }); assertThrows(() => p.x(), TypeError); assertThrows(() => x.callX(p), TypeError); assertThrows(() => X.prototype.x.call(p), TypeError); assertThrows(() => X.prototype.callX(p), TypeError); assertEquals(false, handlerCalled); } // Reference outside of class. { class C { #a() {} } assertThrows('new C().#a()'); } // Duplicate private names. { assertThrows('class C { #a = 1; #a() {} }'); } { class A extends class { } { #a() {} } class D extends class { #c() {} } { #d() {} } class E extends D { #e() {} } new A; new D; new E; } // Super access within private methods. { class A { foo() { return 1; } } class C extends A { #m() { return super.foo; } fn() { return this.#m()(); } } assertEquals(1, new C().fn()); } { assertThrows(() => { class A { [this.#a] = 1; #a() { } } }, TypeError); }