Add initial NativeImage.addRepresentation specs

spec/api-native-image-spec.js

@@ -249,4 +249,31 @@ describe('nativeImage module', () => {
       assert.equal(nativeImage.createFromPath(path.join(__dirname, 'fixtures', 'assets', 'logo.png')).getAspectRatio(), 2.8315789699554443)
     })
   })
+
+  describe('addRepresentation()', () => {
+    it('supports adding a representation for a scale factor', () => {
+      const image = nativeImage.createEmpty()
+      image.addRepresentation({
+        scaleFactor: 1.0,
+        buffer: nativeImage.createFromPath(path.join(__dirname, 'fixtures', 'assets', '1x1.png')).toPNG()
+      })
+      image.addRepresentation({
+        scaleFactor: 2.0,
+        buffer: nativeImage.createFromPath(path.join(__dirname, 'fixtures', 'assets', '2x2.jpg')).toPNG()
+      })
+      image.addRepresentation({
+        scaleFactor: 3.0,
+        buffer: nativeImage.createFromPath(path.join(__dirname, 'fixtures', 'assets', '3x3.png')).toPNG()
+      })
+      image.addRepresentation({
+        scaleFactor: 4.0,
+        buffer: 'invalid'
+      })
+
+      assert.equal(image.toDataURL({scaleFactor: 1.0}), 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAC0lEQVQYlWNgAAIAAAUAAdafFs0AAAAASUVORK5CYII=')
+      assert.equal(image.toDataURL({scaleFactor: 2.0}), 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAYAAABytg0kAAAAFUlEQVQYlWP8////fwYGBgYmBigAAD34BABBrq9BAAAAAElFTkSuQmCC')
+      assert.equal(image.toDataURL({scaleFactor: 3.0}), 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAMAAAADCAYAAABWKLW/AAAADElEQVQYlWNgIAoAAAAnAAGZWEMnAAAAAElFTkSuQmCC')
+      assert.equal(image.toDataURL({scaleFactor: 4.0}), 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAMAAAADCAYAAABWKLW/AAAADElEQVQYlWNgIAoAAAAnAAGZWEMnAAAAAElFTkSuQmCC')
+    })
+  })
 })