Add includes method to typed arrays

src/harmony-array-includes.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, utils) {
 
 'use strict';
 
 %CheckIsBootstrapping();
 
 var GlobalArray = global.Array;
 
 // -------------------------------------------------------------------
 
 // Proposed for ES7
 // https://github.com/tc39/Array.prototype.includes
-// 6e3b78c927aeda20b9d40e81303f9d44596cd904
-function ArrayIncludes(searchElement, fromIndex) {
-  var array = TO_OBJECT(this);
-  var len = $toLength(array.length);
-
-  if (len === 0) {
+// 46c7532ec8499dea3e51aeb940d09e07547ed3f5
+function InnerArrayIncludes(searchElement, fromIndex, array, length) {
+  if (length === 0) {
     return false;
   }
 
   var n = $toInteger(fromIndex);
 
   var k;
   if (n >= 0) {
     k = n;
   } else {
-    k = len + n;
+    k = length + n;
     if (k < 0) {
       k = 0;
     }
   }
 
-  while (k < len) {
+  while (k < length) {
     var elementK = array[k];
     if ($sameValueZero(searchElement, elementK)) {
       return true;
     }
 
     ++k;
   }
 
   return false;
 }
 
+
+function ArrayIncludes(searchElement, fromIndex) {
+  CHECK_OBJECT_COERCIBLE(this, "Array.prototype.includes");
+
+  var array = TO_OBJECT(this);
+  var length = $toLength(array.length);
+
+  return InnerArrayIncludes(searchElement, fromIndex, array, length);
+}
+
+
+function TypedArrayIncludes(searchElement, fromIndex) {
+  if (!%_IsTypedArray(this)) throw MakeTypeError(kNotTypedArray);
+
+  var length = %_TypedArrayGetLength(this);
+
+  return InnerArrayIncludes(searchElement, fromIndex, this, length);
+}
+
 // -------------------------------------------------------------------
 
 %FunctionSetLength(ArrayIncludes, 1);
+%FunctionSetLength(TypedArrayIncludes, 1);
 
-// Set up the non-enumerable functions on the Array prototype object.
+// Set up the non-enumerable function on the Array prototype object.
 utils.InstallFunctions(GlobalArray.prototype, DONT_ENUM, [
   "includes", ArrayIncludes
 ]);
 
+// Set up the non-enumerable function on the typed array prototypes.
+// This duplicates some of the machinery in harmony-typedarray.js in order to
+// keep includes behind the separate --harmony-array-includes flag.
+// TODO(littledan): Fix the TypedArray proto chain (bug v8:4085).
+
+macro TYPED_ARRAYS(FUNCTION)
+// arrayIds below should be synchronized with Runtime_TypedArrayInitialize.
+FUNCTION(Uint8Array)
+FUNCTION(Int8Array)
+FUNCTION(Uint16Array)
+FUNCTION(Int16Array)
+FUNCTION(Uint32Array)
+FUNCTION(Int32Array)
+FUNCTION(Float32Array)
+FUNCTION(Float64Array)
+FUNCTION(Uint8ClampedArray)
+endmacro
+
+macro DECLARE_GLOBALS(NAME)
+var GlobalNAME = global.NAME;
+endmacro
+
+macro EXTEND_TYPED_ARRAY(NAME)
+// Set up non-enumerable functions on the prototype object.
+utils.InstallFunctions(GlobalNAME.prototype, DONT_ENUM, [
+  "includes", TypedArrayIncludes
+]);
+endmacro
+
+TYPED_ARRAYS(DECLARE_GLOBALS)
+TYPED_ARRAYS(EXTEND_TYPED_ARRAY)
+
 })