front_end/testing/test_setup.ts

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

/*
 * This file is automatically loaded and run by Karma because it automatically
 * loads and injects all *.js files it finds.
 */

import '../third_party/chromium/ahem/ahem.js';

import sinon from 'sinon';

import * as Common from '../core/common/common.js';
import * as Host from '../core/host/host.js';
import * as Trace from '../models/trace/trace.js';
import * as TraceSourceMapsResolver from '../models/trace_source_maps_resolver/trace_source_maps_resolver.js';
import * as ThemeSupport from '../ui/legacy/theme_support/theme_support.js';

import {cleanTestDOM, setupTestDOM} from './DOMHooks.js';
import {createFakeSetting, resetHostConfig} from './EnvironmentHelpers.js';
import {TraceLoader} from './TraceLoader.js';
import {
  checkForPendingActivity,
  startTrackingAsyncActivity,
  stopTrackingAsyncActivity,
} from './TrackAsyncOperations.js';

declare global {
  namespace Mocha {
    interface Suite {
      hasOnly?: () => boolean;
    }

    interface Test {
      // Custom extension: attached in beforeEach to signal to Karma that exclusive tests (e.g. it.only) are being run.
      hasExclusiveTests?: boolean;
    }
  }
}

async function setupTestFont() {
  document.documentElement.classList.add('platform-screenshot-test');
  Host.Platform.setFontFamilyForTests('ahem');
}

before(async function() {
  // All setup function should manage their own timeout
  this.timeout(0);
  await setupTestFont();

  // There is no way to provide after each file run via a test set up file.
  // What we do instead is add and after all in all global test suits
  // This is as close as we can get to after each file.
  this.test?.parent?.suites.forEach(function(suite) {
    suite.afterAll(function() {
      TraceLoader.resetCache();
    });
  });
});

beforeEach(async function(this: Mocha.Context) {
  if (this.currentTest) {
    this.currentTest.hasExclusiveTests = this.currentTest.parent?.hasOnly?.();
  }

  stopTrackingAsyncActivity();
  resetHostConfig();
  // Clear out any Sinon stubs or spies between individual tests.
  sinon.restore();
  await setupTestDOM();

  // Ensure that no trace data leaks between tests when testing the trace engine.
  for (const handler of Object.values(Trace.Handlers.ModelHandlers)) {
    handler.reset();
  }
  Trace.Helpers.SyntheticEvents.SyntheticEventsManager.reset();
  TraceSourceMapsResolver.SourceMapsResolver.clearResolvedNodeNames();

  // Don't retain host binding listeners across tests. Set this up before initializing ThemeSupport as
  // ThemeSupport adds a host binding listener.
  Host.InspectorFrontendHost.InspectorFrontendHostInstance.events = new Common.ObjectWrapper.ObjectWrapper();

  // Some unit tests exercise code that assumes a ThemeSupport instance is available.
  // Run this in a beforeEach in case an individual test overrides it.
  const setting = createFakeSetting('ui-theme', 'default');
  ThemeSupport.ThemeSupport.instance({forceNew: true, setting});

  startTrackingAsyncActivity();
});

afterEach(async function() {
  cleanTestDOM(this.currentTest?.fullTitle());
  await checkForPendingActivity(this.currentTest?.fullTitle());
  stopTrackingAsyncActivity();
  // Clear out any Sinon stubs or spies between individual tests.
  sinon.clock?.runToLast();
  sinon.restore();
});