Merge pull request #335 from bocoup/Map

Add tests for Map

test/built-ins/Map/constructor.js

@@ -0,0 +1,10 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1
+description: >
+  The Map constructor is the %Map% intrinsic object and the initial value of the
+  Map property of the global object.
+---*/
+
+assert.sameValue(typeof Map, 'function', 'typeof Map is "function"');

test/built-ins/Map/does-not-throw-when-set-is-not-callable.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Creating a new Map object without arguments doesn't throw if `set` is not
+  callable
+info: >
+  Map ( [ iterable ] )
+
+  When the Set function is called with optional argument iterable the following steps are taken:
+
+  ...
+  5. If iterable is not present, let iterable be undefined.
+  6. If iterable is either undefined or null, let iter be undefined.
+  7. Else,
+    a. Let adder be Get(map, "set").
+    b. ReturnIfAbrupt(adder).
+    c. If IsCallable(adder) is false, throw a TypeError exception.
+    ...
+  8. If iter is undefined, return map.
+  ...
+---*/
+
+Map.prototype.set = null;
+
+var m = new Map();
+
+assert.sameValue(m.size, 0, 'The value of `m.size` is `0`');

test/built-ins/Map/get-set-method-failure.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  new Map returns abrupt from getting Map.prototype.set.
+description: >
+  Map ( [ iterable ] )
+
+  ...
+  7. Else,
+    a. Let adder be Get(map, "add").
+    b. ReturnIfAbrupt(adder).
+---*/
+
+Object.defineProperty(Map.prototype, 'set', {
+  get: function() {
+    throw new Test262Error();
+  }
+});
+
+new Map();
+
+assert.throws(Test262Error, function() {
+  new Map([]);
+});

test/built-ins/Map/iterable-calls-set.js

@@ -0,0 +1,39 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  new Map calls `set` for each item on the iterable argument in order.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    k. Let status be Call(adder, map, «k.[[value]], v.[[value]]»).
+  ...
+includes: [compareArray.js]
+---*/
+
+var mapSet = Map.prototype.set;
+var counter = 0;
+
+var iterable = [["foo", 1], ["bar", 2]];
+var results = [];
+var _this = [];
+
+Map.prototype.set = function(k, v) {
+  counter++;
+  results.push([k, v]);
+  _this.push(this);
+  mapSet.call(this, k, v);
+};
+
+var map = new Map(iterable);
+
+assert.sameValue(counter, 2, "`Map.prototype.set` called twice.");
+
+assert(compareArray(results[0], iterable[0]));
+assert(compareArray(results[1], iterable[1]));
+assert.sameValue(_this[0], map);
+assert.sameValue(_this[1], map);

test/built-ins/Map/iterator-close-after-set-failure.js

@@ -0,0 +1,36 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  The iterator is closed when `Map.prototype.set` throws an error.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    k. Let status be Call(adder, map, «k.[[value]], v.[[value]]»).
+    l. If status is an abrupt completion, return IteratorClose(iter, status).
+features: [Symbol.iterator]
+---*/
+
+var count = 0;
+var iterable = {};
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return { value: [], done: false };
+    },
+    return: function() {
+      count += 1;
+    }
+  };
+};
+Map.prototype.set = function() { throw new Test262Error(); }
+
+assert.throws(Test262Error, function() {
+  new Map(iterable);
+});
+
+assert.sameValue(count, 1);

test/built-ins/Map/iterator-item-first-entry-returns-abrupt.js

@@ -0,0 +1,47 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Closes iterator if item first entry completes abruptly.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    d. Let nextItem be IteratorValue(next).
+    ...
+    g. Let k be Get(nextItem, "0").
+    h. If k is an abrupt completion, return IteratorClose(iter, k).
+    ...
+features: [Symbol.iterator]
+---*/
+
+var count = 0;
+var item = ['foo', 'bar'];
+Object.defineProperty(item, 0, {
+  get: function() {
+    throw new Test262Error();
+  }
+});
+var iterable = {};
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return {
+        value: item,
+        done: false
+      };
+    },
+    return: function() {
+      count++;
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  new Map(iterable);
+});
+
+assert.sameValue(count, 1, 'The get error closed the iterator');

test/built-ins/Map/iterator-item-second-entry-returns-abrupt.js

@@ -0,0 +1,47 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Closes iterator if item second entry completes abruptly.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    d. Let nextItem be IteratorValue(next).
+    ...
+    i. Let v be Get(nextItem, "1").
+    j. If v is an abrupt completion, return IteratorClose(iter, v).
+    ...
+features: [Symbol.iterator]
+---*/
+
+var count = 0;
+var item = ['foo', 'bar'];
+Object.defineProperty(item, 1, {
+  get: function() {
+    throw new Test262Error();
+  }
+});
+var iterable = {};
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return {
+        value: item,
+        done: false
+      };
+    },
+    return: function() {
+      count++;
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  new Map(iterable);
+});
+
+assert.sameValue(count, 1, 'The get error closed the iterator');

test/built-ins/Map/iterator-items-are-not-object-close-iterator.js

@@ -0,0 +1,72 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Closes the iterator after `not Object` error.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    d. Let nextItem be IteratorValue(next).
+    e. ReturnIfAbrupt(nextItem).
+    f. If Type(nextItem) is not Object,
+      i. Let error be Completion{[[type]]: throw, [[value]]: a newly created
+      TypeError object, [[target]]:empty}.
+      ii. Return IteratorClose(iter, error).
+features:
+  - Symbol
+  - Symbol.iterator
+---*/
+
+var count = 0;
+var nextItem;
+var iterable = {};
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return { value: nextItem, done: false };
+    },
+    return: function() {
+      count += 1;
+    }
+  };
+};
+
+nextItem = 1;
+assert.throws(TypeError, function() {
+  new Map(iterable);
+});
+assert.sameValue(count, 1);
+
+nextItem = true;
+assert.throws(TypeError, function() {
+  new Map(iterable);
+});
+assert.sameValue(count, 2);
+
+nextItem = '';
+assert.throws(TypeError, function() {
+  new Map(iterable);
+});
+assert.sameValue(count, 3);
+
+nextItem = null;
+assert.throws(TypeError, function() {
+  new Map(iterable);
+});
+assert.sameValue(count, 4);
+
+nextItem = undefined;
+assert.throws(TypeError, function() {
+  new Map(iterable);
+});
+assert.sameValue(count, 5);
+
+nextItem = Symbol('a');
+assert.throws(TypeError, function() {
+  new Map(iterable);
+});
+assert.sameValue(count, 6);

test/built-ins/Map/iterator-items-are-not-object.js

@@ -0,0 +1,48 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Throws a TypeError if iterable itens are not Objects.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    d. Let nextItem be IteratorValue(next).
+    e. ReturnIfAbrupt(nextItem).
+    f. If Type(nextItem) is not Object,
+      i. Let error be Completion{[[type]]: throw, [[value]]: a newly created
+      TypeError object, [[target]]:empty}.
+      ii. Return IteratorClose(iter, error).
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  new Map([1]);
+});
+
+assert.throws(TypeError, function() {
+  new Map(['']);
+});
+
+assert.throws(TypeError, function() {
+  new Map([true]);
+});
+
+assert.throws(TypeError, function() {
+  new Map([null]);
+});
+
+assert.throws(TypeError, function() {
+  new Map([Symbol('a')]);
+});
+
+assert.throws(TypeError, function() {
+  new Map([undefined]);
+});
+
+assert.throws(TypeError, function() {
+  new Map([['a', 1], 2]);
+});

test/built-ins/Map/iterator-next-failure.js

@@ -0,0 +1,28 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  The iterator is closed when iterable `next` throws an error.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    a. Let next be IteratorStep(iter).
+    b. ReturnIfAbrupt(next).
+features: [Symbol.iterator]
+---*/
+
+var iterable = {};
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      throw new Test262Error();
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  new Map(iterable);
+});

test/built-ins/Map/iterator-value-failure.js

@@ -0,0 +1,34 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  The iterator is closed when iterable `next` value throws an error.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    ...
+    d. Let nextItem be IteratorValue(next).
+    e. ReturnIfAbrupt(nextItem).
+features: [Symbol.iterator]
+---*/
+
+var iterable = {};
+iterable[Symbol.iterator] = function() {
+  return {
+    next: function() {
+      return {
+        get value() {
+          throw new Test262Error();
+        },
+        done: false
+      };
+    }
+  };
+};
+
+assert.throws(Test262Error, function() {
+  new Map(iterable);
+});

test/built-ins/Map/length.js

@@ -0,0 +1,17 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.2
+description: Map.length is 0.
+info: >
+  Properties of the Map Constructor
+
+  Besides the length property (whose value is 0)
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Map.length, 0, 'The value of Map.length is 0');
+
+verifyNotEnumerable(Map, 'length');
+verifyNotWritable(Map, 'length');
+verifyConfigurable(Map, 'length');

test/built-ins/Map/map-iterable-empty-does-not-call-set.js

@@ -0,0 +1,31 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  A Map constructed with an empty iterable argument does not call set.
+info: >
+  Map ( [ iterable ] )
+
+  When the Map function is called with optional argument the following steps are
+  taken:
+
+  ...
+  8. If iter is undefined, return map.
+  9. Repeat
+    a. Let next be IteratorStep(iter).
+    b. ReturnIfAbrupt(next).
+    c. If next is false, return map.
+---*/
+
+var set = Map.prototype.set;
+var counter = 0;
+
+Map.prototype.set = function(value) {
+  counter++;
+  set.call(this, value);
+};
+
+new Map([]);
+
+assert.sameValue(counter, 0, '`Map.prototype.set` was not called.');

test/built-ins/Map/map-iterable-throws-when-set-is-not-callable.js

@@ -0,0 +1,27 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Throws a TypeError if `set` is not callable on Map constructor with a
+  iterable argument.
+info: >
+  Map ( [ iterable ] )
+
+  When the Map function is called with optional argument the following steps are
+  taken:
+
+  ...
+  5. If iterable is not present, let iterable be undefined.
+  6. If iterable is either undefined or null, let iter be undefined.
+  7. Else,
+    a. Let adder be Get(map, "set").
+    b. ReturnIfAbrupt(adder).
+    c. If IsCallable(adder) is false, throw a TypeError exception.
+---*/
+
+Map.prototype.set = null;
+
+assert.throws(TypeError, function() {
+  new Map([[1,1], [2,2]]);
+});

test/built-ins/Map/map-iterable.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Contructor returns a map object set with the elements from the iterable
+  argument.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  9. Repeat
+    a. Let next be IteratorStep(iter).
+    b. ReturnIfAbrupt(next).
+    c. If next is false, return map.
+    ...
+---*/
+
+var m = new Map([
+  [ "attr", 1 ],
+  [ "foo", 2 ]
+]);
+
+assert.sameValue(m.size, 2, 'The value of `m.size` is `2`');
+assert.sameValue(m.get("attr"), 1);
+assert.sameValue(m.get("foo"), 2);

test/built-ins/Map/map-no-iterable-does-not-call-set.js

@@ -0,0 +1,35 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  A Map constructed without a iterable argument does not call set.
+info: >
+  Map ( [ iterable ] )
+
+  When the Map function is called with optional argument the following steps are
+  taken:
+
+  ...
+  5. If iterable is not present, let iterable be undefined.
+  6. If iterable is either undefined or null, let iter be undefined.
+  7. Else,
+    a. Let adder be Get(map, "set").
+    b. ReturnIfAbrupt(adder).
+    c. If IsCallable(adder) is false, throw a TypeError exception.
+    d. Let iter be GetIterator(iterable).
+    e. ReturnIfAbrupt(iter).
+  8. If iter is undefined, return map.
+---*/
+
+var set = Map.prototype.set;
+var counter = 0;
+
+Map.prototype.set = function(value) {
+  counter++;
+  set.call(this, value);
+};
+
+new Map();
+
+assert.sameValue(counter, 0, '`Map.prototype.set` was not called.');

test/built-ins/Map/map-no-iterable.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Returns the new Map object with the new empty list if the iterable argument is
+  undefined.
+info: >
+  Map ( [ iterable ] )
+
+  ...
+  2. Let map be OrdinaryCreateFromConstructor(NewTarget, "%MapPrototype%",
+  «‍[[MapData]]» ).
+  ...
+  4. Map map’s [[MapData]] internal slot to a new empty List.
+  5. If iterable is not present, let iterable be undefined.
+  6. If iterable is either undefined or null, let iter be undefined.
+  ...
+  8. If iter is undefined, return map.
+---*/
+
+var m1 = new Map();
+var m2 = new Map(undefined);
+var m3 = new Map(null);
+
+assert.sameValue(m1.size, 0, 'The value of `new Map().size` is `0`');
+assert.sameValue(m2.size, 0, 'The value of `new Map(undefined).size` is `0`');
+assert.sameValue(m3.size, 0, 'The value of `new Map(null).size` is `0`');
+
+assert(m1 instanceof Map);
+assert(m2 instanceof Map);
+assert(m3 instanceof Map);

test/built-ins/Map/map.js

@@ -0,0 +1,17 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  Map descriptor as a standard built-in object.
+info: >
+  Map ( [ iterable ] )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+verifyNotEnumerable(this, 'Map');
+verifyWritable(this, 'Map');
+verifyConfigurable(this, 'Map');

test/built-ins/Map/name.js

@@ -0,0 +1,18 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: Map.name value and descriptor.
+info: >
+  Map ( [ iterable ] )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Map.name, 'Map', 'The value of Map.name is "Map"');
+
+verifyNotEnumerable(Map, 'name');
+verifyNotWritable(Map, 'name');
+verifyConfigurable(Map, 'name');

test/built-ins/Map/newtarget.js

@@ -0,0 +1,34 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1.1
+description: >
+  The new Map object's prototype is Map.prototype
+info: >
+  Map ( [ iterable ] )
+
+  When the Map function is called with optional argument the following steps
+  are taken:
+
+  ...
+  2. Let map be OrdinaryCreateFromConstructor(NewTarget, "%MapPrototype%",
+  «‍[[MapData]]» ).
+  ...
+
+---*/
+
+var m1 = new Map();
+
+assert.sameValue(
+  Object.getPrototypeOf(m1),
+  Map.prototype,
+  "`Object.getPrototypeOf(m1)` returns `Map.prototype`"
+);
+
+var m2 = new Map([[1, 1], [2, 2]]);
+
+assert.sameValue(
+  Object.getPrototypeOf(m2),
+  Map.prototype,
+  "`Object.getPrototypeOf(m2)` returns `Map.prototype`"
+);

test/built-ins/Map/properties-of-map-instances.js

@@ -0,0 +1,14 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.4
+description: >
+  Map instances are ordinary objects that inherit properties from the Map
+  prototype.
+---*/
+
+assert.sameValue(
+  Object.getPrototypeOf(new Map()),
+  Map.prototype,
+  '`Object.getPrototypeOf(new Map())` returns `Map.prototype`'
+);

test/built-ins/Map/properties-of-the-map-prototype-object.js

@@ -0,0 +1,18 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3
+description: >
+  The prototype of Map.prototype is Object.prototype.
+info: >
+  The Map prototype object is the intrinsic object %MapPrototype%. The value
+  of the [[Prototype]] internal slot of the Map prototype object is the
+  intrinsic object %ObjectPrototype% (19.1.3). The Map prototype object is an
+  ordinary object. It does not have a [[MapData]] internal slot.
+---*/
+
+assert.sameValue(
+  Object.getPrototypeOf(Map.prototype),
+  Object.prototype,
+  'Object.getPrototypeOf(Map.prototype) returns Object.prototype'
+);

test/built-ins/Map/prototype-of-map.js

@@ -0,0 +1,16 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.2
+description: >
+  The prototype of Map is the intrinsic FunctionPrototype.
+info: >
+  The value of the [[Prototype]] internal slot of the Map constructor is the
+  intrinsic object %FunctionPrototype% (19.2.3).
+---*/
+
+assert.sameValue(
+  Object.getPrototypeOf(Map),
+  Function.prototype,
+  '`Object.getPrototypeOf(Map)` returns `Function.prototype`'
+);

test/built-ins/Map/prototype/Symbol.iterator.js

@@ -1,19 +1,19 @@
 // Copyright (C) 2014 the V8 project authors. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
-
 /*---
+es6id: 23.1.3.12
 description: Initial state of the Symbol.iterator property
 info: >
-    The initial value of the @@iterator property is the same function object as
-    the initial value of the entries property.
+  The initial value of the @@iterator property is the same function object as
+  the initial value of the entries property.
 
-    Per ES6 section 17, the method should exist on the Array prototype, and it
-    should be writable and configurable, but not enumerable.
+  Per ES6 section 17, the method should exist on the Array prototype, and it
+  should be writable and configurable, but not enumerable.
 includes: [propertyHelper.js]
 features: [Symbol.iterator]
-es6id: 23.1.3.12
 ---*/
 
+assert.sameValue(Map.prototype[Symbol.iterator], Map.prototype.entries);
 verifyNotEnumerable(Map.prototype, Symbol.iterator);
 verifyWritable(Map.prototype, Symbol.iterator);
 verifyConfigurable(Map.prototype, Symbol.iterator);

test/built-ins/Map/prototype/Symbol.toStringTag/property-descriptor.js

@@ -0,0 +1,21 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.13
+description: >
+  Map.prototype[ @@toStringTag ] value and descriptor.
+includes: [propertyHelper.js]
+features: [Symbol.toStringTag]
+ ---*/
+
+var MapProto = Object.getPrototypeOf(new Map());
+
+assert.sameValue(
+  MapProto[Symbol.toStringTag],
+  'Map',
+  'The value of MapProto[Symbol.toStringTag] is Map'
+);
+
+verifyNotEnumerable(MapProto, Symbol.toStringTag);
+verifyNotWritable(MapProto, Symbol.toStringTag);
+verifyConfigurable(MapProto, Symbol.toStringTag);

test/built-ins/Map/prototype/clear/clear-map.js

@@ -0,0 +1,33 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Clears a Map.
+info: >
+  Map.prototype.clear ( )
+
+  ...
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. Set p.[[key]] to empty.
+    b. Set p.[[value]] to empty.
+  6. Return undefined.
+features: [Symbol]
+---*/
+
+var m1 = new Map([['foo', 'bar'], [1, 1]]);
+var m2 = new Map();
+var m3 = new Map();
+m2.set('foo', 'bar');
+m2.set(1,1);
+m2.set(Symbol('a'), Symbol('a'));
+
+m1.clear();
+m2.clear();
+m3.clear();
+
+assert.sameValue(m1.size, 0);
+assert.sameValue(m2.size, 0);
+assert.sameValue(m3.size, 0);

test/built-ins/Map/prototype/clear/clear.js

@@ -0,0 +1,21 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+    Map.prototype.clear ( )
+
+    17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+    typeof Map.prototype.clear,
+    'function',
+    'typeof Map.prototype.clear is "function"'
+);
+
+verifyNotEnumerable(Map.prototype, 'clear');
+verifyWritable(Map.prototype, 'clear');
+verifyConfigurable(Map.prototype, 'clear');

test/built-ins/Map/prototype/clear/context-is-not-map-object.js

@@ -0,0 +1,23 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Throws a TypeError if `this` does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.clear ( )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call({});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call([]);
+});

test/built-ins/Map/prototype/clear/context-is-not-object.js

@@ -0,0 +1,38 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Throws a TypeError if `this` is not an Object.
+info: >
+  Map.prototype.clear ( )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(true);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call('');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(null);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(undefined);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(Symbol());
+});

test/built-ins/Map/prototype/clear/context-is-set-object-throws.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.clear ( )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(new Set());
+});

test/built-ins/Map/prototype/clear/context-is-weakmap-object-throws.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.clear ( )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.clear.call(new WeakMap());
+});

test/built-ins/Map/prototype/clear/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Map.prototype.clear.length value and descriptor.
+info: >
+  Map.prototype.clear ( )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.clear.length, 0,
+  'The value of `Map.prototype.clear.length` is `0`'
+);
+
+verifyNotEnumerable(Map.prototype.clear, 'length');
+verifyNotWritable(Map.prototype.clear, 'length');
+verifyConfigurable(Map.prototype.clear, 'length');

test/built-ins/Map/prototype/clear/map-data-list-is-preserved.js

@@ -0,0 +1,31 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  The existing [[MapData]] List is preserved.
+info: >
+  The existing [[MapData]] List is preserved because there may be existing
+  MapIterator objects that are suspended midway through iterating over that
+  List.
+
+  Map.prototype.clear ( )
+
+  ...
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. Set p.[[key]] to empty.
+    b. Set p.[[value]] to empty.
+  6. Return undefined.
+---*/
+
+var m = new Map([[1,1], [2,2], [3,3]]);
+var e = m.entries();
+
+e.next();
+m.clear();
+
+var n = e.next();
+assert.sameValue(n.value, undefined);
+assert.sameValue(n.done, true);

test/built-ins/Map/prototype/clear/name.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Map.prototype.entries.name value and descriptor.
+info: >
+  Map.prototype.clear ( )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.clear.name, 'clear',
+  'The value of `Map.prototype.clear.name` is `"clear"`'
+);
+
+verifyNotEnumerable(Map.prototype.clear, 'name');
+verifyNotWritable(Map.prototype.clear, 'name');
+verifyConfigurable(Map.prototype.clear, 'name');

test/built-ins/Map/prototype/clear/returns-undefined.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.1
+description: >
+  Returns undefined.
+info: >
+  Map.prototype.clear ( )
+
+  ...
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. Set p.[[key]] to empty.
+    b. Set p.[[value]] to empty.
+  6. Return undefined.
+---*/
+
+var m1 = new Map([['foo', 'bar'], [1, 1]]);
+
+assert.sameValue(m1.clear(), undefined, 'clears a map and returns undefined');
+assert.sameValue(m1.clear(), undefined, 'returns undefined on an empty map');

test/built-ins/Map/prototype/constructor.js

@@ -0,0 +1,16 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.2
+description: Map.prototype.constructor value and descriptor
+info: >
+  The initial value of Map.prototype.constructor is the intrinsic object %Map%.
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Map.prototype.constructor, Map);
+assert.sameValue((new Map()).constructor, Map);
+
+verifyNotEnumerable(Map.prototype, 'constructor');
+verifyWritable(Map.prototype, 'constructor');
+verifyConfigurable(Map.prototype, 'constructor');

test/built-ins/Map/prototype/delete/context-is-not-map-object.js

@@ -0,0 +1,23 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Throws a TypeError if `this` does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.delete ( key )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call({}, 'attr');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call([], 'attr');
+});

test/built-ins/Map/prototype/delete/context-is-not-object.js

@@ -0,0 +1,38 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Throws a TypeError if `this` is not an Object.
+info: >
+  Map.prototype.delete ( key )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(1, 'attr');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(true, 'attr');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call('', 'attr');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(null, 'attr');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(undefined, 'attr');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(Symbol(), 'attr');
+});

test/built-ins/Map/prototype/delete/context-is-set-object-throws.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.delete ( key )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(new Set(), 'attr');
+});

test/built-ins/Map/prototype/delete/context-is-weakmap-object-throws.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.delete ( key )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.delete.call(new WeakMap(), 'attr');
+});

test/built-ins/Map/prototype/delete/delete.js

@@ -0,0 +1,21 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+    Map.prototype.delete ( )
+
+    17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+    typeof Map.prototype.delete,
+    'function',
+    'typeof Map.prototype.delete is "function"'
+);
+
+verifyNotEnumerable(Map.prototype, 'delete');
+verifyWritable(Map.prototype, 'delete');
+verifyConfigurable(Map.prototype, 'delete');

test/built-ins/Map/prototype/delete/does-not-break-iterators.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Deleting an entry does not break a [[MapData]] List.
+info: >
+  Map.prototype.delete ( key )
+
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true, then
+      i. Set p.[[key]] to empty.
+      ii. Set p.[[value]] to empty.
+      iii. Return true.
+  ...
+---*/
+
+var m = new Map([['a',1], ['b', 2], ['c', 3]]);
+var e = m.entries();
+
+e.next();
+m.delete('b');
+
+var n = e.next();
+
+assert.sameValue(n.value[0], 'c');
+assert.sameValue(n.value[1], 3);
+
+n = e.next();
+assert.sameValue(n.value, undefined);
+assert.sameValue(n.done, true);

test/built-ins/Map/prototype/delete/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Map.prototype.delete.length value and descriptor.
+info: >
+  Map.prototype.delete ( key )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.delete.length, 1,
+  'The value of `Map.prototype.delete.length` is `1`'
+);
+
+verifyNotEnumerable(Map.prototype.delete, 'length');
+verifyNotWritable(Map.prototype.delete, 'length');
+verifyConfigurable(Map.prototype.delete, 'length');

test/built-ins/Map/prototype/delete/name.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Map.prototype.delete.name value and descriptor.
+info: >
+  Map.prototype.delete ( key )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.delete.name, 'delete',
+  'The value of `Map.prototype.delete.name` is `"delete"`'
+);
+
+verifyNotEnumerable(Map.prototype.delete, 'name');
+verifyNotWritable(Map.prototype.delete, 'name');
+verifyConfigurable(Map.prototype.delete, 'name');

test/built-ins/Map/prototype/delete/returns-false.js

@@ -0,0 +1,23 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Returns false when it does not delete an entry.
+info: >
+  Map.prototype.delete ( key )
+
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true, then
+      ...
+      iii. Return true.
+  6. Return false.
+---*/
+
+var m = new Map([['a',1], ['b', 2]]);
+
+assert.sameValue(m.delete('not-in-the-map'), false);
+
+m.delete('a');
+assert.sameValue(m.delete('a'), false);

test/built-ins/Map/prototype/delete/returns-true-for-deleted-entry.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.3
+description: >
+  Returns true when deletes an entry.
+info: >
+  Map.prototype.delete ( key )
+
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true, then
+      i. Set p.[[key]] to empty.
+      ii. Set p.[[value]] to empty.
+      iii. Return true.
+  ...
+---*/
+
+var m = new Map([['a',1], ['b', 2]]);
+
+var result = m.delete('a');
+
+assert(result);
+assert.sameValue(m.size, 1);

test/built-ins/Map/prototype/descriptor.js

@@ -0,0 +1,14 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.2.1
+description: Map.prototype property attributes.
+info: >
+  This property has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+  [[Configurable]]: false }.
+includes: [propertyHelper.js]
+---*/
+
+verifyNotEnumerable(Map, 'prototype');
+verifyNotWritable(Map, 'prototype');
+verifyNotConfigurable(Map, 'prototype');

test/built-ins/Map/prototype/entries-no-map-data.js

@@ -1,13 +0,0 @@
-// Copyright (C) 2014 the V8 project authors. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-
-/*---
-  description: >
-      If the context does not have a [[MapData]] internal slot, throw a
-      TypeError exception as per 23.1.5.1.
-  es6id: 23.1.3.4
- ---*/
-
-assert.throws(TypeError, function() {
-  Map.prototype.entries.call({});
-});

test/built-ins/Map/prototype/entries/does-not-have-mapdata-internal-slot-set.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.entries ( )
+
+  1. Let M be the this value.
+  2. Return CreateMapIterator(M, "key+value").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  2. If map does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(new Set());
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.entries.call(new Set());
+});

test/built-ins/Map/prototype/entries/does-not-have-mapdata-internal-slot-weakmap.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.entries ( )
+
+  1. Let M be the this value.
+  2. Return CreateMapIterator(M, "key+value").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  2. If map does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(new WeakMap());
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.entries.call(new WeakMap());
+});

test/built-ins/Map/prototype/entries/does-not-have-mapdata-internal-slot.js

@@ -0,0 +1,38 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Throws a TypeError if `this` object does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.entries ( )
+
+  1. Let M be the this value.
+  2. Return CreateMapIterator(M, "key+value").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  2. If map does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+
+---*/
+
+var m = new Map();
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call([]);
+});
+
+assert.throws(TypeError, function() {
+  m.entries.call([]);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call({});
+});
+
+assert.throws(TypeError, function() {
+  m.entries.call({});
+});

test/built-ins/Map/prototype/entries/entries.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Property type and descriptor.
+info: >
+  Map.prototype.entries ( )
+
+  17 ECMAScript Standard Built-in Objects
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  typeof Map.prototype.entries,
+  'function',
+  '`typeof Map.prototype.entries` is `function`'
+);
+
+verifyNotEnumerable(Map.prototype, 'entries');
+verifyWritable(Map.prototype, 'entries');
+verifyConfigurable(Map.prototype, 'entries');

test/built-ins/Map/prototype/entries/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Map.prototype.entries.length value and descriptor.
+info: >
+  Map.prototype.entries ( )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.entries.length, 0,
+  'The value of `Map.prototype.entries.length` is `0`'
+);
+
+verifyNotEnumerable(Map.prototype.entries, 'length');
+verifyNotWritable(Map.prototype.entries, 'length');
+verifyConfigurable(Map.prototype.entries, 'length');

test/built-ins/Map/prototype/entries/name.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Map.prototype.entries.name value and descriptor.
+info: >
+  Map.prototype.entries ( )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.entries.name, 'entries',
+  'The value of `Map.prototype.entries.name` is `"entries"`'
+);
+
+verifyNotEnumerable(Map.prototype.entries, 'name');
+verifyNotWritable(Map.prototype.entries, 'name');
+verifyConfigurable(Map.prototype.entries, 'name');

test/built-ins/Map/prototype/entries/returns-iterator-empty.js

@@ -0,0 +1,27 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Returns an iterator on an empty Map object.
+info: >
+  Map.prototype.entries ( )
+
+  ...
+  2. Return CreateMapIterator(M, "key+value").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  7. Return iterator.
+---*/
+
+var map = new Map();
+var iterator = map.entries();
+var result = iterator.next();
+
+assert.sameValue(
+  result.value, undefined,
+  'The value of `result.value` is `undefined`'
+);
+assert.sameValue(result.done, true, 'The value of `result.done` is `true`');

test/built-ins/Map/prototype/entries/returns-iterator.js

@@ -1,36 +1,44 @@
-// Copyright (C) 2014 the V8 project authors. All rights reserved.
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
-
 /*---
-  description: >
-      The method should return a valid iterator with the context as the
-      IteratedObject.
-  es6id: 23.1.3.4
- ---*/
+es6id: 23.1.3.4
+description: >
+  Returns an iterator.
+info: >
+  Map.prototype.entries ( )
+
+  ...
+  2. Return CreateMapIterator(M, "key+value").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  7. Return iterator.
+---*/
 
 var map = new Map();
-map.set(1, 11);
-map.set(2, 22);
-map.set(3, 33);
+map.set('a',1);
+map.set('b',2);
+map.set('c',3);
 
 var iterator = map.entries();
 var result;
 
 result = iterator.next();
-assert.sameValue(result.value[0], 1, 'First result `value` (map key)');
-assert.sameValue(result.value[1], 11, 'First result `value` (map value)');
+assert.sameValue(result.value[0], 'a', 'First result `value` ("key")');
+assert.sameValue(result.value[1], 1, 'First result `value` ("value")');
 assert.sameValue(result.value.length, 2, 'First result `value` (length)');
 assert.sameValue(result.done, false, 'First result `done` flag');
 
 result = iterator.next();
-assert.sameValue(result.value[0], 2, 'Second result `value` (map key)');
-assert.sameValue(result.value[1], 22, 'Second result `value` (map value)');
+assert.sameValue(result.value[0], 'b', 'Second result `value` ("key")');
+assert.sameValue(result.value[1], 2, 'Second result `value` ("value")');
 assert.sameValue(result.value.length, 2, 'Second result `value` (length)');
 assert.sameValue(result.done, false, 'Second result `done` flag');
 
 result = iterator.next();
-assert.sameValue(result.value[0], 3, 'Third result `value` (map key)');
-assert.sameValue(result.value[1], 33, 'Third result `value` (map value)');
+assert.sameValue(result.value[0], 'c', 'Third result `value` ("key")');
+assert.sameValue(result.value[1], 3, 'Third result `value` ("value")');
 assert.sameValue(result.value.length, 2, 'Third result `value` (length)');
 assert.sameValue(result.done, false, 'Third result `done` flag');
 

test/built-ins/Map/prototype/entries/this-not-object-throw.js

@@ -0,0 +1,47 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.4
+description: >
+  Throws a TypeError if `this` is not an Object.
+info: >
+  Map.prototype.entries ( )
+
+  ...
+  2. Return CreateSetIterator(M, "key+value").
+
+  23.1.5.1 CreateSetIterator Abstract Operation
+
+  1. If Type(map) is not Object, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(false);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call('');
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(undefined);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(null);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.entries.call(Symbol());
+});
+
+assert.throws(TypeError, function() {
+  var map = new Map();
+  map.entries.call(false);
+});

test/built-ins/Map/prototype/forEach/callback-parameters.js

@@ -0,0 +1,44 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Verify the parameters order on the given callback.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+  ...
+---*/
+
+var map = new Map();
+map.set('foo', 42);
+map.set('bar', 'baz');
+
+var results = [];
+
+var callback = function(value, key, thisArg) {
+  results.push({
+    value: value,
+    key: key,
+    thisArg: thisArg
+  });
+};
+
+map.forEach(callback);
+
+assert.sameValue(results[0].value, 42);
+assert.sameValue(results[0].key, 'foo');
+assert.sameValue(results[0].thisArg, map);
+
+assert.sameValue(results[1].value, 'baz');
+assert.sameValue(results[1].key, 'bar');
+assert.sameValue(results[1].thisArg, map);
+
+assert.sameValue(results.length, 2);

test/built-ins/Map/prototype/forEach/callback-result-is-abrupt.js

@@ -0,0 +1,28 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Returns error from callback result is abrupt.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+      ii. ReturnIfAbrupt(funcResult).
+  ...
+flags: [noStrict]
+---*/
+
+var map = new Map([[0, 0]]);
+
+assert.throws(Test262Error, function() {
+  map.forEach(function() {
+    throw new Test262Error();
+  });
+});

test/built-ins/Map/prototype/forEach/callback-this-non-strict.js

@@ -0,0 +1,35 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  If a thisArg is not provided, undefined will be used as the this value for
+  each invocation of callbackfn.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+  ...
+flags: [noStrict]
+---*/
+
+var _this = [];
+var map = new Map();
+
+map.set(0, 0);
+map.set(1, 1);
+map.set(2, 2);
+
+map.forEach(function() {
+  _this.push(this);
+});
+
+assert.sameValue(_this[0], this);
+assert.sameValue(_this[1], this);
+assert.sameValue(_this[2], this);

test/built-ins/Map/prototype/forEach/callback-this-strict.js

@@ -0,0 +1,35 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  If a thisArg is not provided, undefined will be used as the this value for
+  each invocation of callbackfn.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+  ...
+flags: [onlyStrict]
+---*/
+
+var _this = [];
+var map = new Map();
+
+map.set(0, 0);
+map.set(1, 1);
+map.set(2, 2);
+
+map.forEach(function() {
+  _this.push(this);
+});
+
+assert.sameValue(_this[0], undefined);
+assert.sameValue(_this[1], undefined);
+assert.sameValue(_this[2], undefined);

test/built-ins/Map/prototype/forEach/deleted-values-during-foreach.js

@@ -0,0 +1,41 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Map state with deleted values during forEach.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+      ii. ReturnIfAbrupt(funcResult).
+  ...
+---*/
+
+var map = new Map();
+map.set('foo', 0);
+map.set('bar', 1);
+
+var count = 0;
+var results = [];
+
+map.forEach(function(value, key) {
+  if (count === 0) {
+    map.delete('bar');
+  }
+  results.push({
+    value: value,
+    key: key
+  });
+  count++;
+});
+
+assert.sameValue(results.length, 1);
+assert.sameValue(results[0].key, 'foo');
+assert.sameValue(results[0].value, 0);

test/built-ins/Map/prototype/forEach/does-not-have-mapdata-internal-slot-set.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(new Set(), function() {});
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.forEach.call(new Set(), function() {});
+});

test/built-ins/Map/prototype/forEach/does-not-have-mapdata-internal-slot-weakmap.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(new WeakMap(), function() {});
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.forEach.call(new WeakMap(), function() {});
+});

test/built-ins/Map/prototype/forEach/does-not-have-mapdata-internal-slot.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Throws a TypeError if `this` object does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+---*/
+
+var m = new Map();
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call([], function() {});
+});
+
+assert.throws(TypeError, function() {
+  m.forEach.call([], function() {});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call({}, function() {});
+});
+
+assert.throws(TypeError, function() {
+  m.forEach.call({}, function() {});
+});

test/built-ins/Map/prototype/forEach/first-argument-is-not-callable.js

@@ -0,0 +1,43 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Throws a TypeError if first argument is not callable.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  4. If IsCallable(callbackfn) is false, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+var map = new Map();
+
+assert.throws(TypeError, function() {
+  map.forEach({});
+});
+
+assert.throws(TypeError, function() {
+  map.forEach([]);
+});
+
+assert.throws(TypeError, function() {
+  map.forEach(1);
+});
+
+assert.throws(TypeError, function() {
+  map.forEach('');
+});
+
+assert.throws(TypeError, function() {
+  map.forEach(null);
+});
+
+assert.throws(TypeError, function() {
+  map.forEach(undefined);
+});
+
+assert.throws(TypeError, function() {
+  map.forEach(Symbol());
+});

test/built-ins/Map/prototype/forEach/forEach.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Property type and descriptor.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  17 ECMAScript Standard Built-in Objects
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  typeof Map.prototype.forEach,
+  'function',
+  '`typeof Map.prototype.forEach` is `function`'
+);
+
+verifyNotEnumerable(Map.prototype, 'forEach');
+verifyWritable(Map.prototype, 'forEach');
+verifyConfigurable(Map.prototype, 'forEach');

test/built-ins/Map/prototype/forEach/iterates-in-key-insertion-order.js

@@ -0,0 +1,51 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Repeats for each non-empty record, in original key insertion order.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+  ...
+---*/
+
+var map = new Map([
+  ['foo', 'valid foo'],
+  ['bar', false],
+  ['baz', 'valid baz']
+]);
+map.set(0, false);
+map.set(1, false);
+map.set(2, 'valid 2');
+map.delete(1);
+map.delete('bar');
+
+// Not setting a new key, just changing the value
+map.set(0, 'valid 0');
+
+var results = [];
+var callback = function(value) {
+  results.push(value);
+};
+
+map.forEach(callback);
+
+assert.sameValue(results[0], 'valid foo');
+assert.sameValue(results[1], 'valid baz');
+assert.sameValue(results[2], 'valid 0');
+assert.sameValue(results[3], 'valid 2');
+assert.sameValue(results.length, 4);
+
+map.clear();
+results = [];
+
+map.forEach(callback);
+assert.sameValue(results.length, 0);

test/built-ins/Map/prototype/forEach/iterates-values-added-after-foreach-begins.js

@@ -0,0 +1,49 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  New keys are visited if created during forEach execution.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+      ii. ReturnIfAbrupt(funcResult).
+  ...
+---*/
+
+var map = new Map();
+map.set('foo', 0);
+map.set('bar', 1);
+
+var count = 0;
+var results = [];
+
+map.forEach(function(value, key) {
+  if (count === 0) {
+    map.set('baz', 2);
+  }
+  results.push({
+    value: value,
+    key: key
+  });
+  count++;
+});
+
+assert.sameValue(count, 3);
+assert.sameValue(map.size, 3);
+
+assert.sameValue(results[0].key, 'foo');
+assert.sameValue(results[0].value, 0);
+
+assert.sameValue(results[1].key, 'bar');
+assert.sameValue(results[1].value, 1);
+
+assert.sameValue(results[2].key, 'baz');
+assert.sameValue(results[2].value, 2);

test/built-ins/Map/prototype/forEach/iterates-values-deleted-then-readded.js

@@ -0,0 +1,50 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  New keys are visited if created during forEach execution.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+      ii. ReturnIfAbrupt(funcResult).
+  ...
+---*/
+
+var map = new Map();
+map.set('foo', 0);
+map.set('bar', 1);
+
+var count = 0;
+var results = [];
+
+map.forEach(function(value, key) {
+  if (count === 0) {
+    map.delete('foo');
+    map.set('foo', 'baz');
+  }
+  results.push({
+    value: value,
+    key: key
+  });
+  count++;
+});
+
+assert.sameValue(count, 3);
+assert.sameValue(map.size, 2);
+
+assert.sameValue(results[0].key, 'foo');
+assert.sameValue(results[0].value, 0);
+
+assert.sameValue(results[1].key, 'bar');
+assert.sameValue(results[1].value, 1);
+
+assert.sameValue(results[2].key, 'foo');
+assert.sameValue(results[2].value, 'baz');

test/built-ins/Map/prototype/forEach/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Map.prototype.forEach.length value and descriptor.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.forEach.length, 1,
+  'The value of `Map.prototype.forEach.length` is `1`'
+);
+
+verifyNotEnumerable(Map.prototype.forEach, 'length');
+verifyNotWritable(Map.prototype.forEach, 'length');
+verifyConfigurable(Map.prototype.forEach, 'length');

test/built-ins/Map/prototype/forEach/name.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Map.prototype.forEach.name value and descriptor.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.forEach.name, 'forEach',
+  'The value of `Map.prototype.forEach.name` is `"forEach"`'
+);
+
+verifyNotEnumerable(Map.prototype.forEach, 'name');
+verifyNotWritable(Map.prototype.forEach, 'name');
+verifyConfigurable(Map.prototype.forEach, 'name');

test/built-ins/Map/prototype/forEach/return-undefined.js

@@ -0,0 +1,27 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Returns undefined.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  8. Return undefined.
+---*/
+
+var map = new Map();
+
+var result = map.forEach(function() {
+  return true;
+});
+
+assert.sameValue(result, undefined, 'Empty map#forEach returns undefined');
+
+map.set(1, 1);
+result = map.forEach(function() {
+  return true;
+});
+
+assert.sameValue(result, undefined, 'map#forEach returns undefined');

test/built-ins/Map/prototype/forEach/second-parameter-as-callback-context.js

@@ -0,0 +1,37 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  If a thisArg parameter is provided, it will be used as the this value for each
+  invocation of callbackfn.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  ...
+  5. If thisArg was supplied, let T be thisArg; else let T be undefined.
+  6. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  7. Repeat for each Record {[[key]], [[value]]} e that is an element of
+  entries, in original key insertion order
+    a. If e.[[key]] is not empty, then
+      i. Let funcResult be Call(callbackfn, T, «e.[[value]], e.[[key]], M»).
+  ...
+---*/
+
+var expectedThis = {};
+var _this = [];
+
+var map = new Map();
+map.set(0, 0);
+map.set(1, 1);
+map.set(2, 2);
+
+var callback = function() {
+  _this.push(this);
+};
+
+map.forEach(callback, expectedThis);
+
+assert.sameValue(_this[0], expectedThis);
+assert.sameValue(_this[1], expectedThis);
+assert.sameValue(_this[2], expectedThis);

test/built-ins/Map/prototype/forEach/this-not-object-throw.js

@@ -0,0 +1,43 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.5
+description: >
+  Throws a TypeError if `this` is not an Object.
+info: >
+  Map.prototype.forEach ( callbackfn [ , thisArg ] )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(false, function() {});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(1, function() {});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call('', function() {});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(undefined, function() {});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(null, function() {});
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.forEach.call(Symbol(), function() {});
+});
+
+assert.throws(TypeError, function() {
+  var map = new Map();
+  map.forEach.call(false, function() {});
+});

test/built-ins/Map/prototype/get/does-not-have-mapdata-internal-slot-set.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.get ( key )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(new Set(), 1);
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.get.call(new Set(), 1);
+});

test/built-ins/Map/prototype/get/does-not-have-mapdata-internal-slot-weakmap.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.get ( key )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(new WeakMap(), 1);
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.get.call(new WeakMap(), 1);
+});

test/built-ins/Map/prototype/get/does-not-have-mapdata-internal-slot.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Throws a TypeError if `this` object does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.get ( key )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+---*/
+
+var m = new Map();
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call([], 1);
+});
+
+assert.throws(TypeError, function() {
+  m.get.call([], 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call({}, 1);
+});
+
+assert.throws(TypeError, function() {
+  m.get.call({}, 1);
+});

test/built-ins/Map/prototype/get/get.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Property type and descriptor.
+info: >
+  Map.prototype.get ( key )
+
+  17 ECMAScript Standard Built-in Objects
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  typeof Map.prototype.get,
+  'function',
+  '`typeof Map.prototype.get` is `function`'
+);
+
+verifyNotEnumerable(Map.prototype, 'get');
+verifyWritable(Map.prototype, 'get');
+verifyConfigurable(Map.prototype, 'get');

test/built-ins/Map/prototype/get/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Map.prototype.get.length value and descriptor.
+info: >
+  Map.prototype.get ( key )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.get.length, 1,
+  'The value of `Map.prototype.get.length` is `1`'
+);
+
+verifyNotEnumerable(Map.prototype.get, 'length');
+verifyNotWritable(Map.prototype.get, 'length');
+verifyConfigurable(Map.prototype.get, 'length');

test/built-ins/Map/prototype/get/name.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Map.prototype.get.name value and descriptor.
+info: >
+  Map.prototype.get ( key )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.get.name, 'get',
+  'The value of `Map.prototype.get.name` is `"get"`'
+);
+
+verifyNotEnumerable(Map.prototype.get, 'name');
+verifyNotWritable(Map.prototype.get, 'name');
+verifyConfigurable(Map.prototype.get, 'name');

test/built-ins/Map/prototype/get/returns-undefined.js

@@ -0,0 +1,41 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Returns undefined when key is not on the map.
+info: >
+  Map.prototype.get ( key )
+
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true,
+    return p.[[value]].
+  6. Return undefined.
+  ...
+---*/
+
+var map = new Map();
+
+assert.sameValue(
+  map.get('item'), undefined,
+ 'returns undefined if key is not on the map'
+);
+
+map.set('item', 1);
+map.set('another_item', 2);
+map.delete('item');
+
+assert.sameValue(
+  map.get('item'), undefined,
+  'returns undefined if key was deleted'
+);
+
+map.set('item', 1);
+map.clear();
+
+assert.sameValue(
+  map.get('item'), undefined,
+  'returns undefined after map is cleared'
+);

test/built-ins/Map/prototype/get/returns-value-different-key-types.js

@@ -0,0 +1,48 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Returns the value from the specified key on different types.
+info: >
+  Map.prototype.get ( key )
+
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true,
+    return p.[[value]].
+  ...
+features: [Symbol]
+---*/
+
+var map = new Map();
+
+map.set('bar', 0);
+assert.sameValue(map.get('bar'), 0);
+
+map.set(1, 42);
+assert.sameValue(map.get(1), 42);
+
+map.set(NaN, 1);
+assert.sameValue(map.get(NaN), 1);
+
+var item = {};
+map.set(item, 2);
+assert.sameValue(map.get(item), 2);
+
+item = [];
+map.set(item, 3);
+assert.sameValue(map.get(item), 3);
+
+item = Symbol('item');
+map.set(item, 4);
+assert.sameValue(map.get(item), 4);
+
+item = null;
+map.set(item, 5);
+assert.sameValue(map.get(item), 5);
+
+item = undefined;
+map.set(item, 6);
+assert.sameValue(map.get(item), 6);

test/built-ins/Map/prototype/get/returns-value-normalized-zero-key.js

@@ -0,0 +1,25 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  -0 and +0 are normalized to +0;
+info: >
+  Map.prototype.get ( key )
+
+  4. Let entries be the List that is the value of M’s [[MapData]] internal slot.
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true,
+    return p.[[value]].
+  ...
+---*/
+
+var map = new Map();
+
+map.set(+0, 42);
+assert.sameValue(map.get(-0), 42);
+
+map = new Map();
+map.set(-0, 43);
+assert.sameValue(map.get(+0), 43);

test/built-ins/Map/prototype/get/this-not-object-throw.js

@@ -0,0 +1,43 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.6
+description: >
+  Throws a TypeError if `this` is not an Object.
+info: >
+  Map.prototype.get ( key )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(false, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(1, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call('', 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(undefined, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(null, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.get.call(Symbol(), 1);
+});
+
+assert.throws(TypeError, function() {
+  var map = new Map();
+  map.get.call(false, 1);
+});

test/built-ins/Map/prototype/has/does-not-have-mapdata-internal-slot-set.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.has ( key )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(new Set(), 1);
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.has.call(new Set(), 1);
+});

test/built-ins/Map/prototype/has/does-not-have-mapdata-internal-slot-weakmap.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.has ( key )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(new WeakMap(), 1);
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.has.call(new WeakMap(), 1);
+});

test/built-ins/Map/prototype/has/does-not-have-mapdata-internal-slot.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Throws a TypeError if `this` object does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.has ( key )
+
+  ...
+  3. If M does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+---*/
+
+var m = new Map();
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call([], 1);
+});
+
+assert.throws(TypeError, function() {
+  m.has.call([], 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call({}, 1);
+});
+
+assert.throws(TypeError, function() {
+  m.has.call({}, 1);
+});

test/built-ins/Map/prototype/has/has.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Property type and descriptor.
+info: >
+  Map.prototype.has ( key )
+
+  17 ECMAScript Standard Built-in Objects
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  typeof Map.prototype.has,
+  'function',
+  '`typeof Map.prototype.has` is `function`'
+);
+
+verifyNotEnumerable(Map.prototype, 'has');
+verifyWritable(Map.prototype, 'has');
+verifyConfigurable(Map.prototype, 'has');

test/built-ins/Map/prototype/has/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Map.prototype.has.length value and descriptor.
+info: >
+  Map.prototype.has ( key )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.has.length, 1,
+  'The value of `Map.prototype.has.length` is `1`'
+);
+
+verifyNotEnumerable(Map.prototype.has, 'length');
+verifyNotWritable(Map.prototype.has, 'length');
+verifyConfigurable(Map.prototype.has, 'length');

test/built-ins/Map/prototype/has/name.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Map.prototype.has.name value and descriptor.
+info: >
+  Map.prototype.has ( key )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Map.prototype.has.name, 'has',
+  'The value of `Map.prototype.has.name` is `"has"`'
+);
+
+verifyNotEnumerable(Map.prototype.has, 'name');
+verifyNotWritable(Map.prototype.has, 'name');
+verifyConfigurable(Map.prototype.has, 'name');

test/built-ins/Map/prototype/has/normalizes-zero-key.js

@@ -0,0 +1,30 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  -0 and +0 are normalized to +0;
+info: >
+  Map.prototype.has ( key )
+
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    a. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true,
+    return true.
+  ...
+---*/
+
+var map = new Map();
+
+assert.sameValue(map.has(-0), false);
+assert.sameValue(map.has(+0), false);
+
+map.set(-0, 42);
+assert.sameValue(map.has(-0), true);
+assert.sameValue(map.has(+0), true);
+
+map.clear();
+
+map.set(+0, 42);
+assert.sameValue(map.has(-0), true);
+assert.sameValue(map.has(+0), true);

test/built-ins/Map/prototype/has/return-false-different-key-types.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Returns true for existing keys, using different key types.
+info: >
+  Map.prototype.has ( key )
+
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    i. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true,
+    return true.
+  ...
+features: [Symbol]
+---*/
+
+var map = new Map();
+
+assert.sameValue(map.has('str'), false);
+assert.sameValue(map.has(1),  false);
+assert.sameValue(map.has(NaN), false);
+assert.sameValue(map.has(true), false);
+assert.sameValue(map.has(false), false);
+assert.sameValue(map.has({}), false);
+assert.sameValue(map.has([]), false);
+assert.sameValue(map.has(Symbol()), false);
+assert.sameValue(map.has(null), false);
+assert.sameValue(map.has(undefined), false);

test/built-ins/Map/prototype/has/return-true-different-key-types.js

@@ -0,0 +1,44 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Returns true for existing keys, using different key types.
+info: >
+  Map.prototype.has ( key )
+
+  5. Repeat for each Record {[[key]], [[value]]} p that is an element of
+  entries,
+    i. If p.[[key]] is not empty and SameValueZero(p.[[key]], key) is true,
+    return true.
+  ...
+features: [Symbol]
+---*/
+
+var map = new Map();
+
+var obj = {};
+var arr = [];
+var symb = Symbol();
+
+map.set('str', undefined);
+map.set(1, undefined);
+map.set(NaN, undefined);
+map.set(true, undefined);
+map.set(false, undefined);
+map.set(obj, undefined);
+map.set(arr, undefined);
+map.set(symb, undefined);
+map.set(null, undefined);
+map.set(undefined, undefined);
+
+assert.sameValue(map.has('str'), true);
+assert.sameValue(map.has(1),  true);
+assert.sameValue(map.has(NaN), true);
+assert.sameValue(map.has(true), true);
+assert.sameValue(map.has(false), true);
+assert.sameValue(map.has(obj), true);
+assert.sameValue(map.has(arr), true);
+assert.sameValue(map.has(symb), true);
+assert.sameValue(map.has(null), true);
+assert.sameValue(map.has(undefined), true);

test/built-ins/Map/prototype/has/this-not-object-throw.js

@@ -0,0 +1,43 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.7
+description: >
+  Throws a TypeError if `this` is not an Object.
+info: >
+  Map.prototype.has ( key )
+
+  1. Let M be the this value.
+  2. If Type(M) is not Object, throw a TypeError exception.
+  ...
+features: [Symbol]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(false, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(1, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call('', 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(undefined, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(null, 1);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.has.call(Symbol(), 1);
+});
+
+assert.throws(TypeError, function() {
+  var map = new Map();
+  map.has.call(false, 1);
+});

test/built-ins/Map/prototype/keys-no-map-data.js

@@ -1,13 +0,0 @@
-// Copyright (C) 2014 the V8 project authors. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-
-/*---
-  description: >
-      If the context does not have a [[MapData]] internal slot, throw a
-      TypeError exception as per 23.1.5.1.
-  es6id: 23.1.3.8
- ---*/
-
-assert.throws(TypeError, function() {
-  Map.prototype.keys.call({});
-});

test/built-ins/Map/prototype/keys/does-not-have-mapdata-internal-slot-set.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.8
+description: >
+  Throws a TypeError if `this` is a Set object.
+info: >
+  Map.prototype.keys ()
+
+  1. Let M be the this value.
+  2. Return CreateMapIterator(M, "key").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  2. If map does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [Set]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.keys.call(new Set());
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.keys.call(new Set());
+});

test/built-ins/Map/prototype/keys/does-not-have-mapdata-internal-slot-weakmap.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.8
+description: >
+  Throws a TypeError if `this` is a WeakMap object.
+info: >
+  Map.prototype.keys ()
+
+  1. Let M be the this value.
+  2. Return CreateMapIterator(M, "key").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  2. If map does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+features: [WeakMap]
+---*/
+
+assert.throws(TypeError, function() {
+  Map.prototype.keys.call(new WeakMap());
+});
+
+assert.throws(TypeError, function() {
+  var m = new Map();
+  m.keys.call(new WeakMap());
+});

test/built-ins/Map/prototype/keys/does-not-have-mapdata-internal-slot.js

@@ -0,0 +1,38 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.8
+description: >
+  Throws a TypeError if `this` object does not have a [[MapData]] internal slot.
+info: >
+  Map.prototype.keys ()
+
+  1. Let M be the this value.
+  2. Return CreateMapIterator(M, "key").
+
+  23.1.5.1 CreateMapIterator Abstract Operation
+
+  ...
+  2. If map does not have a [[MapData]] internal slot, throw a TypeError
+  exception.
+  ...
+
+---*/
+
+var m = new Map();
+
+assert.throws(TypeError, function() {
+  Map.prototype.keys.call([]);
+});
+
+assert.throws(TypeError, function() {
+  m.keys.call([]);
+});
+
+assert.throws(TypeError, function() {
+  Map.prototype.keys.call({});
+});
+
+assert.throws(TypeError, function() {
+  m.keys.call({});
+});

test/built-ins/Map/prototype/keys/keys.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.3.8
+description: >
+  Property type and descriptor.
+info: >
+  Map.prototype.keys ()
+
+  17 ECMAScript Standard Built-in Objects
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  typeof Map.prototype.keys,
+  'function',
+  '`typeof Map.prototype.keys` is `function`'
+);
+
+verifyNotEnumerable(Map.prototype, 'keys');
+verifyWritable(Map.prototype, 'keys');
+verifyConfigurable(Map.prototype, 'keys');