grafana/public/app/plugins/datasource/loki/components/useLokiLabels.test.ts

import { renderHook, act } from 'react-hooks-testing-library';
import LanguageProvider from 'app/plugins/datasource/loki/language_provider';
import { useLokiLabels } from './useLokiLabels';
import { DataSourceStatus } from '@grafana/ui/src/types/datasource';

describe('useLokiLabels hook', () => {
  it('should refresh labels', async () => {
    const datasource = {
      metadataRequest: () => ({ data: { data: [] as any[] } }),
    };
    const languageProvider = new LanguageProvider(datasource);
    const logLabelOptionsMock = ['Holy mock!'];

    languageProvider.refreshLogLabels = () => {
      languageProvider.logLabelOptions = logLabelOptionsMock;
      return Promise.resolve();
    };

    const { result, waitForNextUpdate } = renderHook(() =>
      useLokiLabels(languageProvider, true, [], DataSourceStatus.Connected, DataSourceStatus.Connected)
    );
    act(() => result.current.refreshLabels());
    expect(result.current.logLabelOptions).toEqual([]);
    await waitForNextUpdate();
    expect(result.current.logLabelOptions).toEqual(logLabelOptionsMock);
  });

  it('should force refresh labels after a disconnect', () => {
    const datasource = {
      metadataRequest: () => ({ data: { data: [] as any[] } }),
    };
    const languageProvider = new LanguageProvider(datasource);
    languageProvider.refreshLogLabels = jest.fn();

    renderHook(() =>
      useLokiLabels(languageProvider, true, [], DataSourceStatus.Connected, DataSourceStatus.Disconnected)
    );

    expect(languageProvider.refreshLogLabels).toBeCalledTimes(1);
    expect(languageProvider.refreshLogLabels).toBeCalledWith(true);
  });

  it('should not force refresh labels after a connect', () => {
    const datasource = {
      metadataRequest: () => ({ data: { data: [] as any[] } }),
    };
    const languageProvider = new LanguageProvider(datasource);
    languageProvider.refreshLogLabels = jest.fn();

    renderHook(() =>
      useLokiLabels(languageProvider, true, [], DataSourceStatus.Disconnected, DataSourceStatus.Connected)
    );

    expect(languageProvider.refreshLogLabels).not.toBeCalled();
  });
});