Patch Function#call and Function#apply together, more robust than…

… single fix.

Ref: #304

Changed some code back as mentioned in comments.

Changed more code as per comments

Changed more code as per comments.

Changed some variable names to better reflect comments.

Fixed missed invocation.

Added some comments and code changes as discussed.

[tests] Remove unneeded jshint comment.

[Tests] use the preferred it/skip pattern for this strict mode test.

#345 (comment)
And some other cleanup

Added `arguments` expectations to tests.

Add tests for `Object#toString` of typed arrays and Symbols, if they exist.

Added note about typed array tests.

Fix `hasToStringTagRegExpBug`

Removed RegExp and Array bug detection as can not test, possible Opera 9.
Fixed missing `force` on `defineProperties` that caused the patch to not be applied on IE<9.
Fixed `Uint8ClampedArray` tests for Opera 11 and IE10 that don't have it.

Removed offending test that was moved to detection, but forgotten.

Avoid all possibilities of `call` calling `call`.

Do not pass `undefined` argument, we know IE<9 has unfixable bug.

Final cleanup (hopeully)

Port over work from `apply` fix

Move code so that it is specific to the fix.

Robustness, move before bind.

Remove `Array#slice` tests.

Add notes about `eval` and `apply` avoidance.

es5-shim.js

@@ -55,7 +55,9 @@ var array_splice = ArrayPrototype.splice;
 var array_push = ArrayPrototype.push;
 var array_unshift = ArrayPrototype.unshift;
 var array_concat = ArrayPrototype.concat;
+var str_split = StringPrototype.split;
 var call = FunctionPrototype.call;
+var apply = FunctionPrototype.apply;
 var max = Math.max;
 var min = Math.min;
 
@@ -175,11 +177,160 @@ var ES = {
     }
 };
 
+// Check failure of by-index access of string characters (IE < 9)
+// and failure of `0 in boxedString` (Rhino)
+var boxedString = $Object('a');
+var splitString = boxedString[0] !== 'a' || !(0 in boxedString);
+
 //
 // Function
 // ========
 //
 
+// Tests for inconsistent or buggy `[[Class]]` strings.
+/* eslint-disable no-useless-call */
+var hasToStringTagBasicBug = to_string.call() !== '[object Undefined]' || to_string.call(null) !== '[object Null]';
+/* eslint-enable no-useless-call */
+var hasToStringTagLegacyArguments = to_string.call(arguments) !== '[object Arguments]';
+var hasToStringTagInconsistency = hasToStringTagBasicBug || hasToStringTagLegacyArguments;
+// Others that could be fixed:
+// Older ES3 native functions like `alert` return `[object Object]`.
+// Inconsistent `[[Class]]` strings for `window` or `global`.
+
+var hasApplyArrayLikeDeficiency = (function () {
+    var arrayLike = { length: 4, 0: 1, 2: 4, 3: true };
+    var expectedArray = [1, undefined, 4, true];
+    var actualArray;
+    try {
+        actualArray = (function () {
+            // `array_slice` is safe to use here, no known issue at present.
+            return array_slice.apply(arguments);
+        }.apply(null, arrayLike));
+    } catch (e) {
+        if (to_string.call(actualArray) !== '[object Array]' || actualArray.length !== arrayLike.length) {
+            return true;
+        }
+        while (expectedArray.length) {
+            if (actualArray.pop() !== expectedArray.pop()) {
+                return true;
+            }
+        }
+    }
+    return false;
+}());
+
+var shouldPatchCallApply = hasToStringTagInconsistency || hasApplyArrayLikeDeficiency;
+
+if (shouldPatchCallApply) {
+    // Constant. ES3 maximum array length.
+    var MAX_ARRAY_LENGTH = 4294967295;
+    // To prevent recursion when `call` and `apply` are patched. Robustness.
+    call.call = call;
+    call.apply = apply;
+    apply.call = call;
+    apply.apply = apply;
+}
+
+if (hasToStringTagLegacyArguments) {
+    // This function is for use within `call` and `apply` only.
+    // To avoid any possibility of `call` recursion we use original `hasOwnProperty`.
+    var isDuckTypeArguments = (function (hasOwnProperty) {
+      return function (value) {
+          if (value != null) { // Checks `null` or `undefined`.
+              if (typeof value === 'object' && call.call(hasOwnProperty, value, 'length')) {
+                  var length = value.length;
+                  if (length > -1 && length % 1 === 0 && length <= MAX_ARRAY_LENGTH) {
+                      return !call.call(hasOwnProperty, value, 'arguments') && call.call(hasOwnProperty, value, 'callee');
+                  }
+              }
+          }
+          return false;
+      };
+    }(ObjectPrototype.hasOwnProperty));
+}
+
+if (shouldPatchCallApply) {
+    // For use with `call` and `apply` fixes.
+    var toStringTag = function (value) {
+        // Add whatever fixes for getting `[[Class]]` strings here.
+        if (value === null) {
+            return '[object Null]';
+        }
+        if (typeof value === 'undefined') {
+            return '[object Undefined]';
+        }
+        if (hasToStringTagLegacyArguments && isDuckTypeArguments(value)) {
+            return '[object Arguments]';
+        }
+        // `to_string` is safe to use here, no known issue at present.
+        return call.call(to_string, value);
+    };
+    // For use with `apply` fix.
+    var isArrayLikeObject = function (value) {
+        if (value != null) { // Checks `null` or `undefined`.
+            var type = typeof value;
+            // `to_string` is safe to use here, no known issue at present.
+            if (type === 'object' && type !== 'function' && call.call(to_string, value) !== '[object Function]') {
+                var length = value.length;
+                if (typeof length === 'number') {
+                    return length > -1 && length % 1 === 0 && length <= MAX_ARRAY_LENGTH;
+                }
+            }
+        }
+        return false;
+    };
+}
+
+defineProperties(FunctionPrototype, {
+    // ES-5 15.3.4.3
+    // http://es5.github.io/#x15.3.4.3
+    // The apply() method calls a function with a given this value and arguments
+    // provided as an array (or an array-like object).
+    apply: function (thisArg) {
+        var argsArray = arguments[1];
+        if (arguments.length > 1) {
+            // IE9 (though fix not needed) has a problem here for some reason!!!
+            // Pretty much any function here causes error `SCRIPT5007: Object expected`.
+            if (!isArrayLikeObject(argsArray)) {
+                throw new TypeError('Function.prototype.apply: Arguments list has wrong type');
+            }
+        }
+        // If `this` is `Object#toString`, captured or modified.
+        if (this === to_string || this === Object.prototype.toString) {
+            return toStringTag(thisArg);
+        }
+        // All other applys.
+        if (arguments.length > 1) {
+            // Boxed string access bug fix.
+            if (splitString && to_string.call(thisArg) === '[object String]') {
+                // `str_split` is safe to use here, no known issue at present.
+                argsArray = call.call(str_split, argsArray, '');
+            }
+            // `array_slice` is safe to use here, no known issue at present.
+            argsArray = call.call(array_slice, argsArray);
+        } else {
+            // `argsArray` was `undefined` (not present).
+            argsArray = [];
+        }
+
+        return apply.call(this, thisArg, argsArray);
+    },
+
+    // ES-5 15.3.4.4
+    // http://es5.github.io/#x15.3.4.4
+    // The call() method calls a function with a given this value and arguments
+    // provided individually.
+    call: function (thisArg) {
+        // If `this` is `Object#toString`, captured or modified.
+        if (this === to_string || this === Object.prototype.toString) {
+            return toStringTag(thisArg);
+        }
+        // All other calls.
+        // `array_slice` is safe to use here, no known issue at present.
+        return apply.call(this, thisArg, call.call(array_slice, arguments, 1));
+    }
+}, shouldPatchCallApply);
+
 // ES-5 15.3.4.5
 // http://es5.github.com/#x15.3.4.5
 
@@ -320,7 +471,7 @@ defineProperties(FunctionPrototype, {
 });
 
 // _Please note: Shortcuts are defined after `Function.prototype.bind` as we
-// us it in defining shortcuts.
+// use it in defining shortcuts.
 var owns = call.bind(ObjectPrototype.hasOwnProperty);
 var toStr = call.bind(ObjectPrototype.toString);
 var strSlice = call.bind(StringPrototype.slice);
@@ -371,11 +522,6 @@ defineProperties($Array, { isArray: isArray });
 // http://es5.github.com/#x15.4.4.18
 // https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/array/forEach
 
-// Check failure of by-index access of string characters (IE < 9)
-// and failure of `0 in boxedString` (Rhino)
-var boxedString = $Object('a');
-var splitString = boxedString[0] !== 'a' || !(0 in boxedString);
-
 var properlyBoxesContext = function properlyBoxed(method) {
     // Check node 0.6.21 bug where third parameter is not boxed
     var properlyBoxesNonStrict = true;

tests/spec/s-array.js

@@ -1540,4 +1540,32 @@ describe('Array', function () {
             expect(obj[2]).toBeUndefined();
         });
     });
+
+    describe('#slice()', function () {
+        it('works on arrays', function () {
+            var arr = [1, 2, 3, 4];
+            var result = arr.slice(1, 3);
+            expect(result).toEqual([2, 3]);
+        });
+
+        it('is generic', function () {
+            var obj = { 0: 1, 1: 2, 2: 3, 3: 4, length: 4 };
+            var result = Array.prototype.slice.call(obj, 1, 3);
+            expect(result).toEqual([2, 3]);
+        });
+
+        it('works with arguments', function () {
+            var obj = (function () {
+              return arguments;
+            }(1, 2, 3, 4));
+            var result = Array.prototype.slice.call(obj, 1, 3);
+            expect(result).toEqual([2, 3]);
+        });
+
+        it('boxed string access', function () {
+            var obj = '1234';
+            var result = Array.prototype.slice.call(obj, 1, 3);
+            expect(result).toEqual(['2', '3']);
+        });
+    });
 });

tests/spec/s-function.js

@@ -1,7 +1,84 @@
-/* global describe, it, expect, beforeEach */
+/* global describe, it, xit,  expect, beforeEach */
+var hasStrictMode = (function () {
+    'use strict';
+
+    return !this;
+}());
+var ifHasStrictIt = hasStrictMode ? it : xit;
+var global = Function('return this')();
 
 describe('Function', function () {
-    'use strict';
+    describe('#call()', function () {
+        it('should pass correct arguments', function () {
+            // https://github.com/es-shims/es5-shim/pull/345#discussion_r44878754
+            var result;
+            var testFn = function () {
+                return Array.prototype.slice.call(arguments);
+            };
+            var argsExpected = [null, '1', 1, true, testFn];
+            /* eslint-disable no-useless-call */
+            result = testFn.call(undefined, null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+            result = testFn.call(null, null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+            /* eslint-enable no-useless-call */
+            result = testFn.call('a', null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+            result = testFn.call(1, null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+            result = testFn.call(true, null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+            result = testFn.call(testFn, null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+            result = testFn.call(new Date(), null, '1', 1, true, testFn);
+            expect(result).toEqual(argsExpected);
+        });
+        // https://github.com/es-shims/es5-shim/pull/345#discussion_r44878771
+        ifHasStrictIt('should have correct context in strict mode', function () {
+            'use strict';
+
+            var subject;
+            var testFn = function () {
+                return this;
+            };
+            expect(testFn.call()).toBe(undefined);
+            /* eslint-disable no-useless-call */
+            expect(testFn.call(undefined)).toBe(undefined);
+            expect(testFn.call(null)).toBe(null);
+            /* eslint-enable no-useless-call */
+            expect(testFn.call('a')).toBe('a');
+            expect(testFn.call(1)).toBe(1);
+            expect(testFn.call(true)).toBe(true);
+            expect(testFn.call(testFn)).toBe(testFn);
+            subject = new Date();
+            expect(testFn.call(subject)).toBe(subject);
+        });
+        it('should have correct context in non-strict mode', function () {
+            var result;
+            var subject;
+            var testFn = function () {
+                return this;
+            };
+
+            expect(testFn.call()).toBe(global);
+            /* eslint-disable no-useless-call */
+            expect(testFn.call(undefined)).toBe(global);
+            expect(testFn.call(null)).toBe(global);
+            /* eslint-enable no-useless-call */
+            result = testFn.call('a');
+            expect(typeof result).toBe('object');
+            expect(String(result)).toBe('a');
+            result = testFn.call(1);
+            expect(typeof result).toBe('object');
+            expect(Number(result)).toBe(1);
+            result = testFn.call(true);
+            expect(typeof result).toBe('object');
+            expect(Boolean(result)).toBe(true);
+            expect(testFn.call(testFn)).toBe(testFn);
+            subject = new Date();
+            expect(testFn.call(subject)).toBe(subject);
+        });
+    });
 
     describe('#apply()', function () {
         it('works with arraylike objects', function () {

tests/spec/s-object.js

@@ -1,4 +1,6 @@
-/* global describe, it, xit, expect, beforeEach, jasmine, window */
+/* global describe, it, xit, expect, beforeEach, jasmine, window,
+  ArrayBuffer, Float32Array, Float64Array, Int8Array, Int16Array,
+  Int32Array, Uint8Array, Uint8ClampedArray, Uint16Array, Uint32Array */
 
 var ifWindowIt = typeof window === 'undefined' ? xit : it;
 var extensionsPreventible = typeof Object.preventExtensions === 'function' && (function () {
@@ -22,7 +24,14 @@ var canFreeze = typeof Object.freeze === 'function' && (function () {
     return obj.a !== 3;
 }());
 var ifCanFreezeIt = canFreeze ? it : xit;
-
+var toStr = Object.prototype.toString;
+var noop = function () {};
+var hasIteratorTag = typeof Symbol === 'function' && typeof Symbol.iterator === 'symbol';
+var ifHasIteratorTag = hasIteratorTag ? it : xit;
+var hasArrayBuffer = typeof ArrayBuffer === 'function';
+var ifHasArrayBuffer = hasArrayBuffer ? it : xit;
+var hasUint8ClampedArray = typeof Uint8ClampedArray === 'function';
+var ifHasUint8ClampedArray = hasUint8ClampedArray ? it : xit;
 describe('Object', function () {
     'use strict';
 
@@ -356,4 +365,59 @@ describe('Object', function () {
             expect(obj instanceof Object).toBe(false);
         });
     });
+
+    describe('#toString', function () {
+        it('basic', function () {
+            expect(toStr.call()).toBe('[object Undefined]');
+            /* eslint-disable no-useless-call */
+            expect(toStr.call(undefined)).toBe('[object Undefined]');
+            expect(toStr.call(null)).toBe('[object Null]');
+            /* eslint-enable no-useless-call */
+            expect(toStr.call(1)).toBe('[object Number]');
+            expect(toStr.call(true)).toBe('[object Boolean]');
+            expect(toStr.call('x')).toBe('[object String]');
+            expect(toStr.call([1, 2, 3])).toBe('[object Array]');
+            expect(toStr.call(arguments)).toBe('[object Arguments]');
+            expect(toStr.call({})).toBe('[object Object]');
+            expect(toStr.call(noop)).toBe('[object Function]');
+            expect(toStr.call(new RegExp('c'))).toBe('[object RegExp]');
+            expect(toStr.call(new Date())).toBe('[object Date]');
+            expect(toStr.call(new Error('x'))).toBe('[object Error]');
+        });
+        ifHasArrayBuffer('Typed Arrays', function () {
+            var buffer = new ArrayBuffer(8);
+            expect(toStr.call(buffer)).toBe('[object ArrayBuffer]');
+            expect(toStr.call(new Float32Array(buffer))).toBe('[object Float32Array]');
+            expect(toStr.call(new Float64Array(buffer))).toBe('[object Float64Array]');
+            expect(toStr.call(new Int8Array(buffer))).toBe('[object Int8Array]');
+            expect(toStr.call(new Int16Array(buffer))).toBe('[object Int16Array]');
+            expect(toStr.call(new Int32Array(buffer))).toBe('[object Int32Array]');
+            expect(toStr.call(new Uint8Array(buffer))).toBe('[object Uint8Array]');
+            expect(toStr.call(new Uint16Array(buffer))).toBe('[object Uint16Array]');
+            expect(toStr.call(new Uint32Array(buffer))).toBe('[object Uint32Array]');
+        });
+        ifHasUint8ClampedArray('Uint8ClampedArray', function () {
+            var buffer = new ArrayBuffer(8);
+            expect(toStr.call(new Uint32Array(buffer))).toBe('[object Uint32Array]');
+        });
+        ifHasIteratorTag('Symbol.iterator', function () {
+            expect(toStr.call(Symbol.iterator)).toBe('[object Symbol]');
+        });
+        // https://github.com/es-shims/es5-shim/pull/345#discussion_r44878834
+        it('prototypes', function () {
+            expect(toStr.call(Object.prototype)).toBe('[object Object]');
+            expect(toStr.call(Array.prototype)).toBe('[object Array]');
+            expect(toStr.call(Boolean.prototype)).toBe('[object Boolean]');
+            expect(toStr.call(Function.prototype)).toBe('[object Function]');
+        });
+        // In ES6, many prototype objects stop being instances of themselves,
+        // and instead would return '[object Object]'.
+        xit('prototypes', function () {
+            expect(toStr.call(Number.prototype)).toBe('[object Number]');
+            expect(toStr.call(String.prototype)).toBe('[object String]');
+            expect(toStr.call(Error.prototype)).toBe('[object Error]');
+            expect(toStr.call(Date.prototype)).toBe('[object Date]');
+            expect(toStr.call(RegExp.prototype)).toBe('[object RegExp]');
+        });
+    });
 });