grafana/public/app/features/dashboard/dashgrid/PanelChrome.test.tsx

import React, { FC } from 'react';
import { ReplaySubject } from 'rxjs';
import { Provider } from 'react-redux';
import configureMockStore from 'redux-mock-store';
import { act, render, screen } from '@testing-library/react';
import { EventBusSrv, getDefaultTimeRange, LoadingState, PanelData, PanelPlugin, PanelProps } from '@grafana/data';

import { PanelChrome, Props } from './PanelChrome';
import { DashboardModel, PanelModel } from '../state';
import { PanelQueryRunner } from '../../query/state/PanelQueryRunner';
import { setTimeSrv, TimeSrv } from '../services/TimeSrv';

jest.mock('app/core/profiler', () => ({
  profiler: {
    renderingCompleted: jest.fn(),
  },
}));

function setupTestContext(options: Partial<Props>) {
  const mockStore = configureMockStore<any, any>();
  const store = mockStore({ dashboard: { panels: [] } });
  const subject: ReplaySubject<PanelData> = new ReplaySubject<PanelData>();
  const panelQueryRunner = {
    getData: () => subject,
    run: () => {
      subject.next({ state: LoadingState.Done, series: [], timeRange: getDefaultTimeRange() });
    },
  } as unknown as PanelQueryRunner;
  const timeSrv = {
    timeRange: jest.fn(),
  } as unknown as TimeSrv;
  setTimeSrv(timeSrv);

  const defaults: Props = {
    panel: {
      id: 123,
      hasTitle: jest.fn(),
      replaceVariables: jest.fn(),
      events: { subscribe: jest.fn() },
      getQueryRunner: () => panelQueryRunner,
      getOptions: jest.fn(),
      getDisplayTitle: jest.fn(),
    } as unknown as PanelModel,
    dashboard: {
      panelInitialized: jest.fn(),
      getTimezone: () => 'browser',
      events: new EventBusSrv(),
    } as unknown as DashboardModel,
    plugin: {
      meta: { skipDataQuery: false },
      panel: TestPanelComponent,
    } as unknown as PanelPlugin,
    isViewing: true,
    isEditing: false,
    isInView: false,
    width: 100,
    height: 100,
    onInstanceStateChange: () => {},
  };

  const props = { ...defaults, ...options };
  const { rerender } = render(
    <Provider store={store}>
      <PanelChrome {...props} />
    </Provider>
  );

  return { rerender, props, subject, store };
}

describe('PanelChrome', () => {
  describe('when the user scrolls by a panel so fast that it starts loading data but scrolls out of view', () => {
    it('then it should load the panel successfully when scrolled into view again', () => {
      const { rerender, props, subject, store } = setupTestContext({});

      expect(screen.queryByText(/plugin panel to render/i)).not.toBeInTheDocument();

      act(() => {
        subject.next({ state: LoadingState.Loading, series: [], timeRange: getDefaultTimeRange() });
        subject.next({ state: LoadingState.Done, series: [], timeRange: getDefaultTimeRange() });
      });

      const newProps = { ...props, isInView: true };
      rerender(
        <Provider store={store}>
          <PanelChrome {...newProps} />
        </Provider>
      );

      expect(screen.getByText(/plugin panel to render/i)).toBeInTheDocument();
    });
  });
});

const TestPanelComponent: FC<PanelProps> = () => <div>Plugin Panel to Render</div>;