test-chart-js.the-setup.ts

export function setup() {
  // common
  const router = <Router>(
    (<unknown>jasmine.createSpyObj('router', ['navigate']))
  );
  const canvas = new ElementRef(document.createElement('canvas'));

  // the chart builder
  const chartBuilder = jasmine.createSpy('chart builder');
  // the chart instance
  const chart = jasmine.createSpyObj('The chart instance', [
    'getDataVisibility',
  ]);
  let onClickCallback: Function = () => {};
  chartBuilder.and.callFake((i, o) => {
    onClickCallback = o.options.onClick;
    return chart;
  });

  const builder = {
    router,
    canvas,
    chartBuilder,
    chart,
    build: () => {
      const c = new ChartComponent(router, chartBuilder);
      c.canvas = canvas;
      return c;
    },
    callOnClickWith(index: number) {
      onClickCallback(null, [{ index }]);
    },
    withChartGetDataVisibilityReturning(b: boolean) {
      chart.getDataVisibility.and.return(b);
      return builder;
    },
  };

  return builder;
}