       expect(vr.start).to.be.closeTo(-1.166, 0.01)
       expect(vr.end).to.be.closeTo(1.166, 0.01)
 
-    it "should zoom the x-axis only", ->
+    it "should zoom the x-axis only because dimensions arg is set", ->
       wheel_zoom = new WheelZoomTool({dimensions: ['width']})
 
       @plot.add_tools(wheel_zoom)

      vr = @plot_canvas_view.frame.y_ranges['default']
      expect([vr.start, vr.end]).to.be.deep.equal([-1.0, 1.0])

    it "should zoom the y-axis only", ->
      wheel_zoom = new WheelZoomTool({dimensions: ['height']})

      @plot.add_tools(wheel_zoom)

    beforeEach ->
      utils.stub_canvas()

      # Note default plot dimensions is 600 x 600 (height x width)
      # This is why zooming at {sx: 300, sy: 300} causes the x/y ranges to zoom equally
      @plot = new Plot({
         x_range: new Range1d({start: -1, end: 1})
         y_range: new Range1d({start: -1, end: 1})
