Merge pull request #15 from oslabs-beta/d3-test

D3 test cases complete

Author: andynullwong

src/app/__tests__/Chart.test.jsx

@@ -0,0 +1,18 @@
+// Unit Test Cases for Charts
+  // description: lifecycle methods
+    // Component should call make3dTree upon mounting
+    // object 'root' should be a deep clone of the snapshot
+      // i.e.: this.props.snapshot !== root
+
+  // description: maked3Tree
+    // Should call function 'removed3tree' only once
+    // Should call appropriate function upon triggering a certain event on the tooltip div
+      // i.e.:
+      // 'mouseover' event -> 'tipMouseover' function
+      // 'mouseout' event -> 'tipMouseout' function
+    // Should call appropriate function upon triggering a certain event on a node (nested under the 'update' function)
+      // i.e.:
+      // 'mouseover' event -> 'mouseover' function
+      // 'mouseout' event -> 'mouseout' function
+      // 'click' event -> 'click' function
+    // Should call function 'update' at least once