Ensure isType methods return false for subclassed values.

Former-commit-id: e300d12eb506c6ae4949bd37cf8eb33c3a4be2e1

build.js

@@ -786,6 +786,19 @@
     return (source.match(/(?:\s*\/\/.*)*\n( *)if *\((?:!support\.argsClass|!isArguments)[\s\S]+?};\n\1}/) || [''])[0];
   }
 
+  /**
+   * Gets the `_.isArray` fallback from `source`.
+   *
+   * @private
+   * @param {String} source The source to inspect.
+   * @returns {String} Returns the `isArray` fallback.
+   */
+  function getIsArrayFallback(source) {
+    return matchFunction(source, 'isArray')
+      .replace(/^[\s\S]+?=\s*nativeIsArray\b/, '')
+      .replace(/[;\s]+$/, '');
+  }
+
   /**
    * Gets the `_.isFunction` fallback from `source`.
    *
@@ -1016,6 +1029,17 @@
     return source.replace(getIsArgumentsFallback(source), '');
   }
 
+  /**
+   * Removes the `_.isArray` fallback from `source`.
+   *
+   * @private
+   * @param {String} source The source to process.
+   * @returns {String} Returns the modified source.
+   */
+  function removeIsArrayFallback(source) {
+    return source.replace(getIsArrayFallback(source), '');
+  }
+
   /**
    * Removes the `_.isFunction` fallback from `source`.
    *
@@ -1074,11 +1098,6 @@
   function removeSupportArgsObject(source) {
     source = removeSupportProp(source, 'argsObject');
 
-    // remove `argsAreObjects` from `_.isArray`
-    source = source.replace(matchFunction(source, 'isArray'), function(match) {
-      return match.replace(/\(support\.argsObject\s*&&\s*([^)]+)\)/g, '$1');
-    });
-
     // remove `argsAreObjects` from `_.isEqual`
     source = source.replace(matchFunction(source, 'isEqual'), function(match) {
       return match.replace(/!support.\argsObject[^:]+:\s*/g, '');
@@ -1867,7 +1886,7 @@
 
         // remove native `Array.isArray` branch in `_.isArray`
         source = source.replace(matchFunction(source, 'isArray'), function(match) {
-          return match.replace(/\s*\(nativeIsArray.+/, ' toString.call(value) == arrayClass;');
+          return match.replace(/\bnativeIsArray\s*\|\|\s*/, '');
         });
 
         // replace `_.keys` with `shimKeys`
@@ -1919,6 +1938,7 @@
         source = removeSupportNodeClass(source);
 
         if (!isMobile) {
+          source = removeIsArrayFallback(source);
           source = removeSupportEnumPrototypes(source);
           source = removeSupportNonEnumArgs(source);
 
@@ -2006,11 +2026,6 @@
           source = source.replace(/^( *)var eachIteratorOptions *= *[\s\S]+?\n\1};\n/m, function(match) {
             return match.replace(/(^ *'arrays':)[^,]+/m, '$1 false');
           });
-
-          // remove `toString.call` use from `_.isArray`
-          source = source.replace(matchFunction(source, 'isArray'), function(match) {
-            return match.replace(/\s*\(nativeIsArray.+/, ' nativeIsArray(value);');
-          });
         }
       }
       if (isUnderscore) {
@@ -2535,14 +2550,6 @@
           return match.replace(/\bisEqual\(([^,]+), *([^,]+)[^)]+\)/, '$1 === $2');
         });
 
-        // remove `instanceof` use from `_.isDate`, `_.isFunction`, and `_.isRegExp`
-        _.each(['isDate', 'isFunction', 'isRegExp'], function(methodName) {
-          var snippet = methodName == 'isFunction' ? getIsFunctionFallback(source) : matchFunction(source, methodName);
-          source = source.replace(snippet, function(match) {
-            return match.replace(/\w+\s+instanceof\s+\w+\s*\|\|\s*/g, '');
-          });
-        });
-
         // remove conditional `charCodeCallback` use from `_.max` and `_.min`
         _.each(['max', 'min'], function(methodName) {
           source = source.replace(matchFunction(source, methodName), function(match) {

lodash.js

@@ -943,6 +943,26 @@
       };
     }
 
+    /**
+     * Checks if `value` is an array.
+     *
+     * @static
+     * @memberOf _
+     * @category Objects
+     * @param {Mixed} value The value to check.
+     * @returns {Boolean} Returns `true`, if the `value` is an array, else `false`.
+     * @example
+     *
+     * (function() { return _.isArray(arguments); })();
+     * // => false
+     *
+     * _.isArray([1, 2, 3]);
+     * // => true
+     */
+    var isArray = nativeIsArray || function(value) {
+      return value && typeof value == 'object' && toString.call(value) == arrayClass;
+    };
+
     /**
      * A fallback implementation of `Object.keys` which produces an array of the
      * given object's own enumerable property names.
@@ -1416,29 +1436,6 @@
       return result;
     }
 
-    /**
-     * Checks if `value` is an array.
-     *
-     * @static
-     * @memberOf _
-     * @category Objects
-     * @param {Mixed} value The value to check.
-     * @returns {Boolean} Returns `true`, if the `value` is an array, else `false`.
-     * @example
-     *
-     * (function() { return _.isArray(arguments); })();
-     * // => false
-     *
-     * _.isArray([1, 2, 3]);
-     * // => true
-     */
-    function isArray(value) {
-      // `instanceof` may cause a memory leak in IE 7 if `value` is a host object
-      // http://ajaxian.com/archives/working-aroung-the-instanceof-memory-leak
-      return (support.argsObject && value instanceof Array) ||
-        (nativeIsArray ? nativeIsArray(value) : toString.call(value) == arrayClass);
-    }
-
     /**
      * Checks if `value` is a boolean value.
      *
@@ -1470,7 +1467,7 @@
      * // => true
      */
     function isDate(value) {
-      return value instanceof Date || toString.call(value) == dateClass;
+      return value ? typeof value == 'object' && toString.call(value) == dateClass : false;
     }
 
     /**
@@ -1774,7 +1771,7 @@
     // fallback for older versions of Chrome and Safari
     if (isFunction(/x/)) {
       isFunction = function(value) {
-        return value instanceof Function || toString.call(value) == funcClass;
+        return typeof value == 'function' && toString.call(value) == funcClass;
       };
     }
 
@@ -1924,7 +1921,7 @@
      * // => true
      */
     function isRegExp(value) {
-      return value instanceof RegExp || toString.call(value) == regexpClass;
+      return value ? typeof value == 'object' && toString.call(value) == regexpClass : false;
     }
 
     /**

test/test-build.js

@@ -961,11 +961,6 @@
 
         strictEqual(actual, false, '_.isEqual should ignore `callback` and `thisArg`: ' + basename);
 
-        _.each(['isArray', 'isBoolean', 'isDate', 'isFunction', 'isNumber', 'isRegExp', 'isString'], function(methodName) {
-          var proto = global[methodName.slice(2)].prototype;
-          strictEqual(lodash[methodName](Object.create(proto)), false, '_.' + methodName + ' returns `false` for subclassed values: ' + basename);
-        });
-
         equal(lodash.max('abc'), -Infinity, '_.max should return `-Infinity` for strings: ' + basename);
         equal(lodash.min('abc'), Infinity, '_.min should return `Infinity` for strings: ' + basename);
 

test/test.js

@@ -1611,6 +1611,15 @@
       equal(typeof func({ 'a': 1 }), expected);
       equal(typeof func('a'), expected);
     });
+
+    test('should return `false` for subclassed values', function() {
+      _.each(['isArray', 'isBoolean', 'isDate', 'isFunction', 'isNumber', 'isRegExp', 'isString'], function(methodName) {
+        function Foo() {}
+        Foo.prototype = window[methodName.slice(2)].prototype;
+
+        strictEqual(_[methodName](new Foo), false, '_.' + methodName + ' returns `false`');
+      });
+    });
   });
 
   /*--------------------------------------------------------------------------*/