Improving code coverage

Author: andrefarzat

src/app/plotly/plotly.service.spec.ts

@@ -36,7 +36,7 @@ describe('PlotlyService', () => {
         const plotly = service.getPlotly();
         const methods: (keyof PlotlyService)[] = ['plot', 'update', 'newPlot'];
         methods.forEach(methodName => {
-            spyOn(plotly, methodName);
+            spyOn(plotly, methodName).and.returnValue(new Promise(() => {}));
 
             (service as any)[methodName]('one' as any, 'two' as any, 'three' as any, 'four' as any);
             expect(plotly[methodName]).toHaveBeenCalledWith('one', 'two', 'three', 'four');