Expose memoized function's cache. [closes #265]

Former-commit-id: fc44676386854ec9d5fd7a4fac8583508d63949f

build/pre-compile.js

@@ -93,6 +93,7 @@
     'bind',
     'bindAll',
     'bindKey',
+    'cache',
     'clearTimeout',
     'clone',
     'cloneDeep',

lodash.js

@@ -4615,13 +4615,16 @@
      * });
      */
     function memoize(func, resolver) {
-      var cache = {};
-      return function() {
-        var key = keyPrefix + (resolver ? resolver.apply(this, arguments) : arguments[0]);
+      function memoized() {
+        var cache = memoized.cache,
+            key = keyPrefix + (resolver ? resolver.apply(this, arguments) : arguments[0]);
+
         return hasOwnProperty.call(cache, key)
           ? cache[key]
           : (cache[key] = func.apply(this, arguments));
-      };
+      }
+      memoized.cache = {};
+      return memoized;
     }
 
     /**

test/test.js

@@ -1900,6 +1900,22 @@
 
   /*--------------------------------------------------------------------------*/
 
+  QUnit.module('lodash.memoize');
+
+  (function() {
+    test('should expose a `cache` object on the `memoized` function', function() {
+      var memoized = _.memoize(_.identity);
+      memoized('x');
+
+      var cache = memoized.cache,
+          key = _.keys(cache)[0];
+
+      equal(cache[key], 'x');
+    });
+  }());
+
+  /*--------------------------------------------------------------------------*/
+
   QUnit.module('lodash.merge');
 
   (function() {