Issue #414: part1: add opacity to Layer model

test/js/model/LayerTest.js

@@ -0,0 +1,39 @@
+describe("Layer model test", function() {
+
+  beforeEach(function() {});
+  afterEach(function() {});
+
+  it("has proper defaults", function() {
+    var layer = new pskl.model.Layer('layerName');
+
+    expect(layer.getOpacity()).toBe(1);
+    expect(layer.getFrames().length).toBe(0);
+    expect(layer.getName()).toBe('layerName');
+  });
+
+  it("can set opacity", function() {
+    var layer = new pskl.model.Layer('layerName');
+
+    layer.setOpacity(0.5);
+    expect(layer.getOpacity()).toBe(0.5);
+  });
+
+  it("ignores bad opacity", function() {
+    var layer = new pskl.model.Layer('layerName');
+
+    layer.setOpacity(0.3);
+    expect(layer.getOpacity()).toBe(0.3);
+
+    layer.setOpacity('Yep I\'m an opacity, let me in !');
+    expect(layer.getOpacity()).toBe(0.3);
+
+    layer.setOpacity(9000);
+    expect(layer.getOpacity()).toBe(0.3);
+
+    layer.setOpacity(-1);
+    expect(layer.getOpacity()).toBe(0.3);
+
+    layer.setOpacity(null);
+    expect(layer.getOpacity()).toBe(0.3);
+  });
+});