v8/test/mjsunit/harmony/weakrefs/basics.js

// Copyright 2018 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-weak-refs

(function TestConstructWeakFactory() {
  let wf = new WeakFactory(() => {});
  assertEquals(wf.toString(), "[object WeakFactory]");
  assertNotSame(wf.__proto__, Object.prototype);
  assertSame(wf.__proto__.__proto__, Object.prototype);
})();

(function TestWeakFactoryConstructorCallAsFunction() {
  let caught = false;
  let message = "";
  try {
    let f = WeakFactory(() => {});
  } catch (e) {
    message = e.message;
    caught = true;
  } finally {
    assertTrue(caught);
    assertEquals(message, "Constructor WeakFactory requires 'new'");
  }
})();

(function TestConstructWeakFactoryCleanupNotCallable() {
  let message = "WeakFactory: cleanup must be callable";
  assertThrows(() => { let wf = new WeakFactory(); }, TypeError, message);
  assertThrows(() => { let wf = new WeakFactory(1); }, TypeError, message);
  assertThrows(() => { let wf = new WeakFactory(null); }, TypeError, message);
})();

(function TestConstructWeakFactoryWithCallableProxyAsCleanup() {
  let handler = {};
  let obj = () => {};
  let proxy = new Proxy(obj, handler);
  let wf = new WeakFactory(proxy);
})();

(function TestConstructWeakFactoryWithNonCallableProxyAsCleanup() {
  let message = "WeakFactory: cleanup must be callable";
  let handler = {};
  let obj = {};
  let proxy = new Proxy(obj, handler);
  assertThrows(() => { let wf = new WeakFactory(proxy); }, TypeError, message);
})();

(function TestMakeCell() {
  let wf = new WeakFactory(() => {});
  let wc = wf.makeCell({});
  assertEquals(wc.toString(), "[object WeakCell]");
  assertNotSame(wc.__proto__, Object.prototype);
  assertSame(wc.__proto__.__proto__, Object.prototype);
  assertEquals(wc.holdings, undefined);

  let holdings_desc = Object.getOwnPropertyDescriptor(wc.__proto__, "holdings");
  assertEquals(true, holdings_desc.configurable);
  assertEquals(false, holdings_desc.enumerable);
  assertEquals("function", typeof holdings_desc.get);
  assertEquals(undefined, holdings_desc.set);

  let clear_desc = Object.getOwnPropertyDescriptor(wc.__proto__, "clear");
  assertEquals(true, clear_desc.configurable);
  assertEquals(false, clear_desc.enumerable);
  assertEquals("function", typeof clear_desc.value);
})();

(function TestMakeCellWithHoldings() {
  let wf = new WeakFactory(() => {});
  let obj = {a: 1};
  let holdings = {b: 2};
  let wc = wf.makeCell(obj, holdings);
  assertSame(wc.holdings, holdings);
})();

(function TestMakeCellWithHoldingsSetHoldings() {
  let wf = new WeakFactory(() => {});
  let obj = {a: 1};
  let holdings = {b: 2};
  let wc = wf.makeCell(obj, holdings);
  assertSame(wc.holdings, holdings);
  wc.holdings = 5;
  assertSame(wc.holdings, holdings);
})();

(function TestMakeCellWithHoldingsSetHoldingsStrict() {
  "use strict";
  let wf = new WeakFactory(() => {});
  let obj = {a: 1};
  let holdings = {b: 2};
  let wc = wf.makeCell(obj, holdings);
  assertSame(wc.holdings, holdings);
  assertThrows(() => { wc.holdings = 5; }, TypeError);
  assertSame(wc.holdings, holdings);
})();

(function TestMakeCellWithNonObject() {
  let wf = new WeakFactory(() => {});
  let message = "WeakFactory.prototype.makeCell: target must be an object";
  assertThrows(() => wf.makeCell(), TypeError, message);
  assertThrows(() => wf.makeCell(1), TypeError, message);
  assertThrows(() => wf.makeCell(false), TypeError, message);
  assertThrows(() => wf.makeCell("foo"), TypeError, message);
  assertThrows(() => wf.makeCell(Symbol()), TypeError, message);
  assertThrows(() => wf.makeCell(null), TypeError, message);
  assertThrows(() => wf.makeCell(undefined), TypeError, message);
})();

(function TestMakeCellWithProxy() {
  let handler = {};
  let obj = {};
  let proxy = new Proxy(obj, handler);
  let wf = new WeakFactory(() => {});
  let wc = wf.makeCell(proxy);
})();

(function TestMakeCellTargetAndHoldingsSameValue() {
  let wf = new WeakFactory(() => {});
  let obj = {a: 1};
  // SameValue(target, holdings) not ok
  assertThrows(() => wf.makeCell(obj, obj), TypeError,
               "WeakFactory.prototype.makeCell: target and holdings must not be same");
  let holdings = {a: 1};
  let wc = wf.makeCell(obj, holdings);
})();

(function TestMakeCellWithoutWeakFactory() {
  assertThrows(() => WeakFactory.prototype.makeCell.call({}, {}), TypeError);
  // Does not throw:
  let wf = new WeakFactory(() => {});
  WeakFactory.prototype.makeCell.call(wf, {});
})();

(function TestHoldingsWithoutWeakCell() {
  let wf = new WeakFactory(() => {});
  let wc = wf.makeCell({});
  let holdings_getter = Object.getOwnPropertyDescriptor(wc.__proto__, "holdings").get;
  assertThrows(() => holdings_getter.call({}), TypeError);
  // Does not throw:
  holdings_getter.call(wc);
})();

(function TestClearWithoutWeakCell() {
  let wf = new WeakFactory(() => {});
  let wc = wf.makeCell({});
  let clear = Object.getOwnPropertyDescriptor(wc.__proto__, "clear").value;
  assertThrows(() => clear.call({}), TypeError);
  // Does not throw:
  clear.call(wc);
})();

(function TestWeakRefConstructor() {
  let wr = new WeakRef({});
  assertEquals(wr.toString(), "[object WeakRef]");
  assertNotSame(wr.__proto__, Object.prototype);

  let deref_desc = Object.getOwnPropertyDescriptor(wr.__proto__, "deref");
  assertEquals(true, deref_desc.configurable);
  assertEquals(false, deref_desc.enumerable);
  assertEquals("function", typeof deref_desc.value);
})();

(function TestWeakRefConstructorWithNonObject() {
  let message = "WeakRef: target must be an object";
  assertThrows(() => new WeakRef(), TypeError, message);
  assertThrows(() => new WeakRef(1), TypeError, message);
  assertThrows(() => new WeakRef(false), TypeError, message);
  assertThrows(() => new WeakRef("foo"), TypeError, message);
  assertThrows(() => new WeakRef(Symbol()), TypeError, message);
  assertThrows(() => new WeakRef(null), TypeError, message);
  assertThrows(() => new WeakRef(undefined), TypeError, message);
})();

(function TestWeakRefConstructorCallAsFunction() {
  let caught = false;
  let message = "";
  try {
    let f = WeakRef({});
  } catch (e) {
    message = e.message;
    caught = true;
  } finally {
    assertTrue(caught);
    assertEquals(message, "Constructor WeakRef requires 'new'");
  }
})();

(function TestWeakRefWithProxy() {
  let handler = {};
  let obj = {};
  let proxy = new Proxy(obj, handler);
  let wr = new WeakRef(proxy);
})();

(function TestCleanupSomeWithoutWeakFactory() {
  assertThrows(() => WeakFactory.prototype.cleanupSome.call({}), TypeError);
  // Does not throw:
  let wf = new WeakFactory(() => {});
  let rv = WeakFactory.prototype.cleanupSome.call(wf);
  assertEquals(undefined, rv);
})();

(function TestDerefWithoutWeakRef() {
  let wf = new WeakFactory(() => {});
  let wc = wf.makeCell({});
  let wr = new WeakRef({});
  let deref = Object.getOwnPropertyDescriptor(wr.__proto__, "deref").value;
  assertThrows(() => deref.call({}), TypeError);
  assertThrows(() => deref.call(wc), TypeError);
  // Does not throw:
  deref.call(wr);
})();