Hide ImageValue base constructor

Author: wilddamon

src/css-image-value.js

@@ -14,48 +14,47 @@
 
 (function(internal, scope) {
 
-  (function() {
-    function CSSImageValue() {
-      throw new TypeError("Can\'t instantiate CSSImageValue");
-    }
-    internal.inherit(CSSImageValue, CSSResourceValue);
+  function onLoad() {
+    this.state = "loaded";
+    this.intrinsicWidth = this._image.naturalWidth;
+    this.intrinsicHeight = this._image.naturalHeight;
+    if (this.intrinsicHeight != 0)
+      this.intrinsicRatio = this.intrinsicWidth / this.intrinsicHeight;
+  }
 
-    scope.CSSImageValue = CSSImageValue;
-  })();
+  function onError() {
+    this.state = "error";
+  }
 
-  var CSSImageValue = function(image) {
-    if (!(image instanceof Image)) {
-      throw new TypeError("image must be an Image object");
-    }
+  function onProgress() {
+    this.state = "loading";
+  }
 
-    function onLoad() {
-      this.state = "loaded";
-      this.intrinsicWidth = this._image.naturalWidth;
-      this.intrinsicHeight = this._image.naturalHeight;
-      if (this.intrinsicHeight != 0)
-        this.intrinsicRatio = this.intrinsicWidth / this.intrinsicHeight;
-    }
+  var CSSImageValue = function() {
+    throw new TypeError('CSSImageValue cannot be instantiated');
+  }
+  internal.inherit(CSSImageValue, CSSResourceValue);
 
-    function onError() {
-      this.state = "error";
-    }
+  scope.CSSImageValue = CSSImageValue;
 
-    function onProgress() {
-      this.state = "loading";
+  (function() {
+    function CSSImageValue(image) {
+      if (!(image instanceof Image)) {
+        throw new TypeError("image must be an Image object");
+      }
+
+      this._image = image;
+      this.state = "unloaded";
+      this.intrinsicWidth = null;
+      this.intrinsicHeight = null;
+      this.intrinsicRatio = null;
+      this._image.onload = onLoad.bind(this);
+      this._image.onerror = onError.bind(this);
+      this._image.onprogess = onProgress.bind(this);
     }
+    CSSImageValue.prototype = Object.create(scope.CSSImageValue.prototype);
 
-    this._image = image;
-    this.state = "unloaded";
-    this.intrinsicWidth = null;
-    this.intrinsicHeight = null;
-    this.intrinsicRatio = null;
-    this._image.onload = onLoad.bind(this);
-    this._image.onerror = onError.bind(this);
-    this._image.onprogess = onProgress.bind(this);
-  }
-
-  CSSImageValue.prototype = Object.create(scope.CSSImageValue.prototype);
-
-  internal.CSSImageValue = CSSImageValue;
+    internal.CSSImageValue = CSSImageValue;
+  })();
 
 })(typedOM.internal, window);

src/css-url-image-value.js

@@ -19,12 +19,12 @@
       throw new TypeError("URL must be a string");
     }
     internal.CSSImageValue.call(this, new Image());
+
     this._image.src = url;
     this.url = url;
     this.cssText = 'url(' + this.url + ')';
   }
-
-  internal.inherit(CSSURLImageValue, internal.CSSImageValue);
+  internal.inherit(CSSURLImageValue, CSSImageValue);
 
   scope.CSSURLImageValue = CSSURLImageValue;
 

test/js/css-image-value.js

@@ -13,10 +13,9 @@
 // limitations under the License.
 
 suite('CSSImageValue', function() {
-  test('Can only create internal CSSImageValue object', function() {
-    var instantiateErr = /^Can't instantiate CSSImageValue$/;
+  test('Cannot instantiate base CSSImageValue', function() {
+    var instantiateErr = /^CSSImageValue cannot be instantiated$/;
     assert.throws(function() { new CSSImageValue(new Image()); }, TypeError, instantiateErr);
-    assert.doesNotThrow(function() { new typedOM.internal.CSSImageValue(new Image()); });
   });
 
   test('CSSImageValue object is a CSSImageValue, CSSResourceValue, and CSSStyleValue', function() {

test/js/css-url-image-value.js

@@ -14,10 +14,11 @@
 
 suite('CSSURLImageValue', function() {
   test('CSSURLImageValue is a CSSURLImageValue, CSSImageValue, CSSResourceValue, and CSSStyleValue', function() {
-    assert.instanceOf(new CSSURLImageValue('resources/1x1-green.png'), CSSURLImageValue);
-    assert.instanceOf(new CSSURLImageValue('resources/1x1-green.png'), CSSImageValue);
-    assert.instanceOf(new CSSURLImageValue('resources/1x1-green.png'), CSSResourceValue);
-    assert.instanceOf(new CSSURLImageValue('resources/1x1-green.png'), CSSStyleValue);
+    var imageValue = new CSSURLImageValue('resources/1x1-green.png');
+    assert.instanceOf(imageValue, CSSURLImageValue);
+    assert.instanceOf(imageValue, CSSImageValue);
+    assert.instanceOf(imageValue, CSSResourceValue);
+    assert.instanceOf(imageValue, CSSStyleValue);
   });
 
   test('CSSURLImageValue only accepts string', function() {