Support sinon fake timers #1187

import { configure } from '@testing-library/react';
import sinon from 'sinon';

configure({
  asyncWrapper: async (cb) => {
    // our tests run only in the browser but this should more properly be getIsReactActEnvironment()
    const previousActEnvironment = window.IS_REACT_ACT_ENVIRONMENT;
    window.IS_REACT_ACT_ENVIRONMENT = false;
    try {
      const result = await cb();
      // Drain microtask queue.
      // Otherwise we'll restore the previous act() environment, before we resolve the `waitFor` call.
      // The caller would have no chance to wrap the in-flight Promises in `act()`
      await new Promise(resolve => {
        setTimeout(() => {
          resolve();
        }, 0);
        // run callbacks if we've mocked out global timers
        if (window.Date.isFake) {
          sinon.clock.tick(0);
        }
      });
      return result;
    } finally {
      window.IS_REACT_ACT_ENVIRONMENT = previousActEnvironment;
    }
  },
});