[Plot] Fill in specs

Fill in specs for elements used by the PlotController
in order to improve coverage of the plot bundle.
WTD-533.

platform/features/plot/test/elements/PlotTickGeneratorSpec.js

@@ -9,6 +9,46 @@ define(
         "use strict";
 
         describe("A plot tick generator", function () {
+            var mockPanZoomStack,
+                mockFormatter,
+                generator;
+
+            beforeEach(function () {
+                mockPanZoomStack = jasmine.createSpyObj(
+                    "panZoomStack",
+                    [ "getPanZoom" ]
+                );
+                mockFormatter = jasmine.createSpyObj(
+                    "formatter",
+                    [ "formatDomainValue", "formatRangeValue" ]
+                );
+
+                mockPanZoomStack.getPanZoom.andReturn({
+                    origin: [ 0, 0 ],
+                    dimensions: [ 100, 100 ]
+                });
+
+                generator =
+                    new PlotTickGenerator(mockPanZoomStack, mockFormatter);
+            });
+
+            it("provides tick marks for range", function () {
+                expect(generator.generateRangeTicks(11).length).toEqual(11);
+
+                // Should have used range formatter
+                expect(mockFormatter.formatRangeValue).toHaveBeenCalled();
+                expect(mockFormatter.formatDomainValue).not.toHaveBeenCalled();
+
+            });
+
+            it("provides tick marks for domain", function () {
+                expect(generator.generateDomainTicks(11).length).toEqual(11);
+
+                // Should have used domain formatter
+                expect(mockFormatter.formatRangeValue).not.toHaveBeenCalled();
+                expect(mockFormatter.formatDomainValue).toHaveBeenCalled();
+            });
+
         });
     }
 );