Consistent undefined check and default test cache

mustache.js

@@ -504,7 +504,9 @@
    * Clears all cached templates in this writer.
    */
   Writer.prototype.clearCache = function clearCache () {
-    this.templateCache !== undefined && this.templateCache.clear();
+    if (typeof this.templateCache !== 'undefined') {
+      this.templateCache.clear();
+    }
   };
 
   /**
@@ -676,6 +678,9 @@
     Writer: undefined,
     set templateCache (cache) {
       defaultWriter.templateCache = cache;
+    },
+    get templateCache () {
+      return defaultWriter.templateCache;
     }
   };
 

mustache.mjs

@@ -497,7 +497,9 @@ function Writer () {
  * Clears all cached templates in this writer.
  */
 Writer.prototype.clearCache = function clearCache () {
-  this.templateCache !== undefined && this.templateCache.clear();
+  if (typeof this.templateCache !== 'undefined') {
+    this.templateCache.clear();
+  }
 };
 
 /**
@@ -669,6 +671,9 @@ var mustache = {
   Writer: undefined,
   set templateCache (cache) {
     defaultWriter.templateCache = cache;
+  },
+  get templateCache () {
+    return defaultWriter.templateCache;
   }
 };
 

test/parse-test.js

@@ -56,20 +56,14 @@ var expectations = {
                                             : [ [ '#', 'foo', 0, 8, [ [ '#', 'a', 11, 17, [ [ 'text', '    ', 18, 22 ], [ 'name', 'b', 22, 27 ], [ 'text', '\n', 27, 28 ] ], 30 ] ], 37 ] ]
 };
 
+var originalTemplateCache;
+before(function () {
+  originalTemplateCache = Mustache.templateCache;
+});
+
 beforeEach(function (){
   Mustache.clearCache();
-  Mustache.templateCache = {
-    _cache: {},
-    set: function set (key, value) {
-      this._cache[key] = value;
-    },
-    get: function get (key) {
-      return this._cache[key];
-    },
-    clear: function clear () {
-      this._cache = {};
-    }
-  };
+  Mustache.templateCache = originalTemplateCache;
 });
 
 describe('Mustache.parse', function () {