electron/spec/api-web-contents-spec.js

'use strict';

const ChildProcess = require('child_process');
const fs = require('fs');
const http = require('http');
const path = require('path');
const { closeWindow } = require('./window-helpers');
const { emittedOnce } = require('./events-helpers');
const chai = require('chai');
const dirtyChai = require('dirty-chai');

const features = process.electronBinding('features');
const { ipcRenderer, remote, clipboard } = require('electron');
const { BrowserWindow, webContents, ipcMain, session } = remote;
const { expect } = chai;

const isCi = remote.getGlobal('isCi');

chai.use(dirtyChai);

/* The whole webContents API doesn't use standard callbacks */
/* eslint-disable standard/no-callback-literal */

describe('webContents module', () => {
  const fixtures = path.resolve(__dirname, 'fixtures');
  let w;

  beforeEach(() => {
    w = new BrowserWindow({
      show: false,
      width: 400,
      height: 400,
      webPreferences: {
        backgroundThrottling: false,
        nodeIntegration: true,
        webviewTag: true
      }
    });
  });

  afterEach(() => closeWindow(w).then(() => { w = null; }));

  describe('loadURL() promise API', () => {
    it('resolves when done loading', async () => {
      await expect(w.loadURL('about:blank')).to.eventually.be.fulfilled;
    });

    it('resolves when done loading a file URL', async () => {
      await expect(w.loadFile(path.join(fixtures, 'pages', 'base-page.html'))).to.eventually.be.fulfilled;
    });

    it('rejects when failing to load a file URL', async () => {
      await expect(w.loadURL('file:non-existent')).to.eventually.be.rejected
        .and.have.property('code', 'ERR_FILE_NOT_FOUND');
    });

    // Temporarily disable on WOA until
    // https://github.com/electron/electron/issues/20008 is resolved
    const testFn = (process.platform === 'win32' && process.arch === 'arm64' ? it.skip : it);
    testFn('rejects when loading fails due to DNS not resolved', async () => {
      await expect(w.loadURL('https://err.name.not.resolved')).to.eventually.be.rejected
        .and.have.property('code', 'ERR_NAME_NOT_RESOLVED');
    });

    it('rejects when navigation is cancelled due to a bad scheme', async () => {
      await expect(w.loadURL('bad-scheme://foo')).to.eventually.be.rejected
        .and.have.property('code', 'ERR_FAILED');
    });

    it('sets appropriate error information on rejection', async () => {
      let err;
      try {
        await w.loadURL('file:non-existent');
      } catch (e) {
        err = e;
      }
      expect(err).not.to.be.null();
      expect(err.code).to.eql('ERR_FILE_NOT_FOUND');
      expect(err.errno).to.eql(-6);
      expect(err.url).to.eql(process.platform === 'win32' ? 'file://non-existent/' : 'file:///non-existent');
    });

    it('rejects if the load is aborted', async () => {
      const s = http.createServer((req, res) => { /* never complete the request */ });
      await new Promise(resolve => s.listen(0, '127.0.0.1', resolve));
      const { port } = s.address();
      const p = expect(w.loadURL(`http://127.0.0.1:${port}`)).to.eventually.be.rejectedWith(Error, /ERR_ABORTED/);
      // load a different file before the first load completes, causing the
      // first load to be aborted.
      await w.loadFile(path.join(fixtures, 'pages', 'base-page.html'));
      await p;
      s.close();
    });

    it("doesn't reject when a subframe fails to load", async () => {
      let resp = null;
      const s = http.createServer((req, res) => {
        res.writeHead(200, { 'Content-Type': 'text/html' });
        res.write('<iframe src="http://err.name.not.resolved"></iframe>');
        resp = res;
        // don't end the response yet
      });
      await new Promise(resolve => s.listen(0, '127.0.0.1', resolve));
      const { port } = s.address();
      const p = new Promise(resolve => {
        w.webContents.on('did-fail-load', (event, errorCode, errorDescription, validatedURL, isMainFrame, frameProcessId, frameRoutingId) => {
          if (!isMainFrame) {
            resolve();
          }
        });
      });
      const main = w.loadURL(`http://127.0.0.1:${port}`);
      await p;
      resp.end();
      await main;
      s.close();
    });

    it("doesn't resolve when a subframe loads", async () => {
      let resp = null;
      const s = http.createServer((req, res) => {
        res.writeHead(200, { 'Content-Type': 'text/html' });
        res.write('<iframe src="data:text/html,hi"></iframe>');
        resp = res;
        // don't end the response yet
      });
      await new Promise(resolve => s.listen(0, '127.0.0.1', resolve));
      const { port } = s.address();
      const p = new Promise(resolve => {
        w.webContents.on('did-frame-finish-load', (event, errorCode, errorDescription, validatedURL, isMainFrame, frameProcessId, frameRoutingId) => {
          if (!isMainFrame) {
            resolve();
          }
        });
      });
      const main = w.loadURL(`http://127.0.0.1:${port}`);
      await p;
      resp.destroy(); // cause the main request to fail
      await expect(main).to.eventually.be.rejected
        .and.have.property('errno', -355); // ERR_INCOMPLETE_CHUNKED_ENCODING
      s.close();
    });
  });

  describe('getFocusedWebContents() API', () => {
    it('returns the focused web contents', (done) => {
      if (isCi) return done();

      const specWebContents = remote.getCurrentWebContents();
      expect(specWebContents.id).to.equal(webContents.getFocusedWebContents().id);

      specWebContents.once('devtools-opened', () => {
        expect(specWebContents.devToolsWebContents.id).to.equal(webContents.getFocusedWebContents().id);
        specWebContents.closeDevTools();
      });

      specWebContents.once('devtools-closed', () => {
        expect(specWebContents.id).to.equal(webContents.getFocusedWebContents().id);
        done();
      });

      specWebContents.openDevTools();
    });

    it('does not crash when called on a detached dev tools window', (done) => {
      const specWebContents = w.webContents;

      specWebContents.once('devtools-opened', () => {
        expect(() => {
          webContents.getFocusedWebContents();
        }).to.not.throw();
        specWebContents.closeDevTools();
      });

      specWebContents.once('devtools-closed', () => {
        expect(() => {
          webContents.getFocusedWebContents();
        }).to.not.throw();
        done();
      });

      specWebContents.openDevTools({ mode: 'detach' });
      w.inspectElement(100, 100);
    });
  });

  describe('setDevToolsWebContents() API', () => {
    it('sets arbitrary webContents as devtools', async () => {
      const devtools = new BrowserWindow({ show: false });
      const promise = emittedOnce(devtools.webContents, 'dom-ready');
      w.webContents.setDevToolsWebContents(devtools.webContents);
      w.webContents.openDevTools();
      await promise;
      expect(devtools.getURL().startsWith('devtools://devtools')).to.be.true();
      const result = await devtools.webContents.executeJavaScript('InspectorFrontendHost.constructor.name');
      expect(result).to.equal('InspectorFrontendHostImpl');
      devtools.destroy();
    });
  });

  describe('isFocused() API', () => {
    it('returns false when the window is hidden', () => {
      BrowserWindow.getAllWindows().forEach((window) => {
        expect(!window.isVisible() && window.webContents.isFocused()).to.be.false();
      });
    });
  });

  describe('isCurrentlyAudible() API', () => {
    it('returns whether audio is playing', async () => {
      const webContents = remote.getCurrentWebContents();
      const context = new window.AudioContext();
      // Start in suspended state, because of the
      // new web audio api policy.
      context.suspend();
      const oscillator = context.createOscillator();
      oscillator.connect(context.destination);
      oscillator.start();
      let p = emittedOnce(webContents, '-audio-state-changed');
      await context.resume();
      await p;
      expect(webContents.isCurrentlyAudible()).to.be.true();
      p = emittedOnce(webContents, '-audio-state-changed');
      oscillator.stop();
      await p;
      expect(webContents.isCurrentlyAudible()).to.be.false();
      oscillator.disconnect();
      context.close();
    });
  });

  describe('getWebPreferences() API', () => {
    it('should not crash when called for devTools webContents', (done) => {
      w.webContents.openDevTools();
      w.webContents.once('devtools-opened', () => {
        expect(w.devToolsWebContents.getWebPreferences()).to.be.null();
        done();
      });
    });
  });

  describe('openDevTools() API', () => {
    it('can show window with activation', async () => {
      const focused = emittedOnce(w, 'focus');
      w.show();
      await focused;
      expect(w.isFocused()).to.be.true();
      const devtoolsOpened = emittedOnce(w.webContents, 'devtools-opened');
      w.webContents.openDevTools({ mode: 'detach', activate: true });
      await devtoolsOpened;
      expect(w.isFocused()).to.be.false();
    });

    it('can show window without activation', async () => {
      const devtoolsOpened = emittedOnce(w.webContents, 'devtools-opened');
      w.webContents.openDevTools({ mode: 'detach', activate: false });
      await devtoolsOpened;
      expect(w.isDevToolsOpened()).to.be.true();
    });
  });

  describe('before-input-event event', () => {
    it('can prevent document keyboard events', async () => {
      await w.loadFile(path.join(fixtures, 'pages', 'key-events.html'));
      const keyDown = new Promise(resolve => {
        ipcMain.once('keydown', (event, key) => resolve(key));
      });
      ipcRenderer.sendSync('prevent-next-input-event', 'a', w.webContents.id);
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'a' });
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'b' });
      expect(await keyDown).to.equal('b');
    });

    it('has the correct properties', async () => {
      await w.loadFile(path.join(fixtures, 'pages', 'base-page.html'));
      const testBeforeInput = async (opts) => {
        const modifiers = [];
        if (opts.shift) modifiers.push('shift');
        if (opts.control) modifiers.push('control');
        if (opts.alt) modifiers.push('alt');
        if (opts.meta) modifiers.push('meta');
        if (opts.isAutoRepeat) modifiers.push('isAutoRepeat');

        const p = emittedOnce(w.webContents, 'before-input-event');
        w.webContents.sendInputEvent({
          type: opts.type,
          keyCode: opts.keyCode,
          modifiers: modifiers
        });
        const [, input] = await p;

        expect(input.type).to.equal(opts.type);
        expect(input.key).to.equal(opts.key);
        expect(input.code).to.equal(opts.code);
        expect(input.isAutoRepeat).to.equal(opts.isAutoRepeat);
        expect(input.shift).to.equal(opts.shift);
        expect(input.control).to.equal(opts.control);
        expect(input.alt).to.equal(opts.alt);
        expect(input.meta).to.equal(opts.meta);
      };
      await testBeforeInput({
        type: 'keyDown',
        key: 'A',
        code: 'KeyA',
        keyCode: 'a',
        shift: true,
        control: true,
        alt: true,
        meta: true,
        isAutoRepeat: true
      });
      await testBeforeInput({
        type: 'keyUp',
        key: '.',
        code: 'Period',
        keyCode: '.',
        shift: false,
        control: true,
        alt: true,
        meta: false,
        isAutoRepeat: false
      });
      await testBeforeInput({
        type: 'keyUp',
        key: '!',
        code: 'Digit1',
        keyCode: '1',
        shift: true,
        control: false,
        alt: false,
        meta: true,
        isAutoRepeat: false
      });
      await testBeforeInput({
        type: 'keyUp',
        key: 'Tab',
        code: 'Tab',
        keyCode: 'Tab',
        shift: false,
        control: true,
        alt: false,
        meta: false,
        isAutoRepeat: true
      });
    });
  });

  describe('zoom-changed', () => {
    beforeEach(function () {
      // On Mac, zooming isn't done with the mouse wheel.
      if (process.platform === 'darwin') {
        return closeWindow(w).then(() => {
          w = null;
          this.skip();
        });
      }
    });

    it('is emitted with the correct zooming info', async () => {
      w.loadFile(path.join(fixtures, 'pages', 'base-page.html'));
      await emittedOnce(w.webContents, 'did-finish-load');

      const testZoomChanged = async ({ zoomingIn }) => {
        const promise = emittedOnce(w.webContents, 'zoom-changed');

        w.webContents.sendInputEvent({
          type: 'mousewheel',
          x: 300,
          y: 300,
          deltaX: 0,
          deltaY: zoomingIn ? 1 : -1,
          wheelTicksX: 0,
          wheelTicksY: zoomingIn ? 1 : -1,
          phase: 'began',
          modifiers: ['control', 'meta']
        });

        const [, zoomDirection] = await promise;
        expect(zoomDirection).to.equal(zoomingIn ? 'in' : 'out');
      };

      await testZoomChanged({ zoomingIn: true });
      await testZoomChanged({ zoomingIn: false });
    });
  });

  describe('devtools window', () => {
    let testFn = it;
    if (process.platform === 'darwin' && isCi) {
      testFn = it.skip;
    }
    if (process.platform === 'win32' && isCi) {
      testFn = it.skip;
    }
    try {
      // We have other tests that check if native modules work, if we fail to require
      // robotjs let's skip this test to avoid false negatives
      require('robotjs');
    } catch (err) {
      testFn = it.skip;
    }

    testFn('can receive and handle menu events', async function () {
      this.timeout(5000);
      w.show();
      w.loadFile(path.join(fixtures, 'pages', 'key-events.html'));
      // Ensure the devtools are loaded
      w.webContents.closeDevTools();
      const opened = emittedOnce(w.webContents, 'devtools-opened');
      w.webContents.openDevTools();
      await opened;
      await emittedOnce(w.webContents.devToolsWebContents, 'did-finish-load');
      w.webContents.devToolsWebContents.focus();

      // Focus an input field
      await w.webContents.devToolsWebContents.executeJavaScript(
        `const input = document.createElement('input');
        document.body.innerHTML = '';
        document.body.appendChild(input)
        input.focus();`
      );

      // Write something to the clipboard
      clipboard.writeText('test value');

      // Fake a paste request using robotjs to emulate a REAL keyboard paste event
      require('robotjs').keyTap('v', process.platform === 'darwin' ? ['command'] : ['control']);

      const start = Date.now();
      let val;

      // Check every now and again for the pasted value (paste is async)
      while (val !== 'test value' && Date.now() - start <= 1000) {
        val = await w.webContents.devToolsWebContents.executeJavaScript(
          `document.querySelector('input').value`
        );
        await new Promise(resolve => setTimeout(resolve, 10));
      }

      // Once we're done expect the paste to have been successful
      expect(val).to.equal('test value', 'value should eventually become the pasted value');
    });
  });

  describe('sendInputEvent(event)', () => {
    beforeEach(async () => {
      await w.loadFile(path.join(fixtures, 'pages', 'key-events.html'));
    });

    it('can send keydown events', (done) => {
      ipcMain.once('keydown', (event, key, code, keyCode, shiftKey, ctrlKey, altKey) => {
        expect(key).to.equal('a');
        expect(code).to.equal('KeyA');
        expect(keyCode).to.equal(65);
        expect(shiftKey).to.be.false();
        expect(ctrlKey).to.be.false();
        expect(altKey).to.be.false();
        done();
      });
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'A' });
    });

    it('can send keydown events with modifiers', (done) => {
      ipcMain.once('keydown', (event, key, code, keyCode, shiftKey, ctrlKey, altKey) => {
        expect(key).to.equal('Z');
        expect(code).to.equal('KeyZ');
        expect(keyCode).to.equal(90);
        expect(shiftKey).to.be.true();
        expect(ctrlKey).to.be.true();
        expect(altKey).to.be.false();
        done();
      });
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'Z', modifiers: ['shift', 'ctrl'] });
    });

    it('can send keydown events with special keys', (done) => {
      ipcMain.once('keydown', (event, key, code, keyCode, shiftKey, ctrlKey, altKey) => {
        expect(key).to.equal('Tab');
        expect(code).to.equal('Tab');
        expect(keyCode).to.equal(9);
        expect(shiftKey).to.be.false();
        expect(ctrlKey).to.be.false();
        expect(altKey).to.be.true();
        done();
      });
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'Tab', modifiers: ['alt'] });
    });

    it('can send char events', (done) => {
      ipcMain.once('keypress', (event, key, code, keyCode, shiftKey, ctrlKey, altKey) => {
        expect(key).to.equal('a');
        expect(code).to.equal('KeyA');
        expect(keyCode).to.equal(65);
        expect(shiftKey).to.be.false();
        expect(ctrlKey).to.be.false();
        expect(altKey).to.be.false();
        done();
      });
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'A' });
      w.webContents.sendInputEvent({ type: 'char', keyCode: 'A' });
    });

    it('can send char events with modifiers', (done) => {
      ipcMain.once('keypress', (event, key, code, keyCode, shiftKey, ctrlKey, altKey) => {
        expect(key).to.equal('Z');
        expect(code).to.equal('KeyZ');
        expect(keyCode).to.equal(90);
        expect(shiftKey).to.be.true();
        expect(ctrlKey).to.be.true();
        expect(altKey).to.be.false();
        done();
      });
      w.webContents.sendInputEvent({ type: 'keyDown', keyCode: 'Z' });
      w.webContents.sendInputEvent({ type: 'char', keyCode: 'Z', modifiers: ['shift', 'ctrl'] });
    });
  });

  it('supports inserting CSS', async () => {
    w.loadURL('about:blank');
    await w.webContents.insertCSS('body { background-repeat: round; }');
    const result = await w.webContents.executeJavaScript('window.getComputedStyle(document.body).getPropertyValue("background-repeat")');
    expect(result).to.equal('round');
  });

  it('supports removing inserted CSS', async () => {
    w.loadURL('about:blank');
    const key = await w.webContents.insertCSS('body { background-repeat: round; }');
    await w.webContents.removeInsertedCSS(key);
    const result = await w.webContents.executeJavaScript('window.getComputedStyle(document.body).getPropertyValue("background-repeat")');
    expect(result).to.equal('repeat');
  });

  it('supports inspecting an element in the devtools', (done) => {
    w.loadURL('about:blank');
    w.webContents.once('devtools-opened', () => { done(); });
    w.webContents.inspectElement(10, 10);
  });

  describe('startDrag({file, icon})', () => {
    it('throws errors for a missing file or a missing/empty icon', () => {
      expect(() => {
        w.webContents.startDrag({ icon: path.join(fixtures, 'assets', 'logo.png') });
      }).to.throw(`Must specify either 'file' or 'files' option`);

      expect(() => {
        w.webContents.startDrag({ file: __filename });
      }).to.throw(`Must specify 'icon' option`);

      if (process.platform === 'darwin') {
        expect(() => {
          w.webContents.startDrag({ file: __filename, icon: __filename });
        }).to.throw(`Must specify non-empty 'icon' option`);
      }
    });
  });

  describe('focus()', () => {
    describe('when the web contents is hidden', () => {
      it('does not blur the focused window', (done) => {
        ipcMain.once('answer', (event, parentFocused, childFocused) => {
          expect(parentFocused).to.be.true();
          expect(childFocused).to.be.false();
          done();
        });
        w.show();
        w.loadFile(path.join(fixtures, 'pages', 'focus-web-contents.html'));
      });
    });
  });

  describe('getOSProcessId()', () => {
    it('returns a valid procress id', async () => {
      expect(w.webContents.getOSProcessId()).to.equal(0);

      await w.loadURL('about:blank');
      expect(w.webContents.getOSProcessId()).to.be.above(0);
    });
  });

  describe('zoom api', () => {
    const zoomScheme = remote.getGlobal('zoomScheme');
    const hostZoomMap = {
      host1: 0.3,
      host2: 0.7,
      host3: 0.2
    };

    before((done) => {
      const protocol = session.defaultSession.protocol;
      protocol.registerStringProtocol(zoomScheme, (request, callback) => {
        const response = `<script>
                            const {ipcRenderer, remote} = require('electron')
                            ipcRenderer.send('set-zoom', window.location.hostname)
                            ipcRenderer.on(window.location.hostname + '-zoom-set', () => {
                              const { zoomLevel } = remote.getCurrentWebContents()
                              ipcRenderer.send(window.location.hostname + '-zoom-level', zoomLevel)
                            })
                          </script>`;
        callback({ data: response, mimeType: 'text/html' });
      }, (error) => done(error));
    });

    after((done) => {
      const protocol = session.defaultSession.protocol;
      protocol.unregisterProtocol(zoomScheme, (error) => done(error));
    });

    // TODO(codebytere): remove in Electron v8.0.0
    it('can set the correct zoom level (functions)', async () => {
      try {
        await w.loadURL('about:blank');
        const zoomLevel = w.webContents.getZoomLevel();
        expect(zoomLevel).to.eql(0.0);
        w.webContents.setZoomLevel(0.5);
        const newZoomLevel = w.webContents.getZoomLevel();
        expect(newZoomLevel).to.eql(0.5);
      } finally {
        w.webContents.setZoomLevel(0);
      }
    });

    it('can set the correct zoom level', async () => {
      try {
        await w.loadURL('about:blank');
        const zoomLevel = w.webContents.zoomLevel;
        expect(zoomLevel).to.eql(0.0);
        w.webContents.zoomLevel = 0.5;
        const newZoomLevel = w.webContents.zoomLevel;
        expect(newZoomLevel).to.eql(0.5);
      } finally {
        w.webContents.zoomLevel = 0;
      }
    });

    it('can persist zoom level across navigation', (done) => {
      let finalNavigation = false;
      ipcMain.on('set-zoom', (e, host) => {
        const zoomLevel = hostZoomMap[host];
        if (!finalNavigation) w.webContents.zoomLevel = zoomLevel;
        console.log();
        e.sender.send(`${host}-zoom-set`);
      });
      ipcMain.on('host1-zoom-level', (e, zoomLevel) => {
        const expectedZoomLevel = hostZoomMap.host1;
        expect(zoomLevel).to.equal(expectedZoomLevel);
        if (finalNavigation) {
          done();
        } else {
          w.loadURL(`${zoomScheme}://host2`);
        }
      });
      ipcMain.once('host2-zoom-level', (e, zoomLevel) => {
        const expectedZoomLevel = hostZoomMap.host2;
        expect(zoomLevel).to.equal(expectedZoomLevel);
        finalNavigation = true;
        w.webContents.goBack();
      });
      w.loadURL(`${zoomScheme}://host1`);
    });

    it('can propagate zoom level across same session', (done) => {
      const w2 = new BrowserWindow({
        show: false
      });
      w2.webContents.on('did-finish-load', () => {
        const zoomLevel1 = w.webContents.zoomLevel;
        expect(zoomLevel1).to.equal(hostZoomMap.host3);

        const zoomLevel2 = w2.webContents.zoomLevel;
        expect(zoomLevel1).to.equal(zoomLevel2);
        w2.setClosable(true);
        w2.close();
        done();
      });
      w.webContents.on('did-finish-load', () => {
        w.webContents.zoomLevel = hostZoomMap.host3;
        w2.loadURL(`${zoomScheme}://host3`);
      });
      w.loadURL(`${zoomScheme}://host3`);
    });

    it('cannot propagate zoom level across different session', (done) => {
      const w2 = new BrowserWindow({
        show: false,
        webPreferences: {
          partition: 'temp'
        }
      });
      const protocol = w2.webContents.session.protocol;
      protocol.registerStringProtocol(zoomScheme, (request, callback) => {
        callback('hello');
      }, (error) => {
        if (error) return done(error);
        w2.webContents.on('did-finish-load', () => {
          const zoomLevel1 = w.webContents.zoomLevel;
          expect(zoomLevel1).to.equal(hostZoomMap.host3);

          const zoomLevel2 = w2.webContents.zoomLevel;
          expect(zoomLevel2).to.equal(0);
          expect(zoomLevel1).to.not.equal(zoomLevel2);

          protocol.unregisterProtocol(zoomScheme, (error) => {
            if (error) return done(error);
            w2.setClosable(true);
            w2.close();
            done();
          });
        });
        w.webContents.on('did-finish-load', () => {
          w.webContents.zoomLevel = hostZoomMap.host3;
          w2.loadURL(`${zoomScheme}://host3`);
        });
        w.loadURL(`${zoomScheme}://host3`);
      });
    });

    it('can persist when it contains iframe', (done) => {
      const server = http.createServer((req, res) => {
        setTimeout(() => {
          res.end();
        }, 200);
      });
      server.listen(0, '127.0.0.1', () => {
        const url = 'http://127.0.0.1:' + server.address().port;
        const content = `<iframe src=${url}></iframe>`;
        w.webContents.on('did-frame-finish-load', (e, isMainFrame) => {
          if (!isMainFrame) {
            const zoomLevel = w.webContents.zoomLevel;
            expect(zoomLevel).to.equal(2.0);

            w.webContents.zoomLevel = 0;
            server.close();
            done();
          }
        });
        w.webContents.on('dom-ready', () => {
          w.webContents.zoomLevel = 2.0;
        });
        w.loadURL(`data:text/html,${content}`);
      });
    });

    it('cannot propagate when used with webframe', (done) => {
      let finalZoomLevel = 0;
      const w2 = new BrowserWindow({
        show: false
      });
      w2.webContents.on('did-finish-load', () => {
        const zoomLevel1 = w.webContents.zoomLevel;
        expect(zoomLevel1).to.equal(finalZoomLevel);

        const zoomLevel2 = w2.webContents.zoomLevel;
        expect(zoomLevel2).to.equal(0);
        expect(zoomLevel1).to.not.equal(zoomLevel2);

        w2.setClosable(true);
        w2.close();
        done();
      });
      ipcMain.once('temporary-zoom-set', (e, zoomLevel) => {
        w2.loadFile(path.join(fixtures, 'pages', 'c.html'));
        finalZoomLevel = zoomLevel;
      });
      w.loadFile(path.join(fixtures, 'pages', 'webframe-zoom.html'));
    });

    it('cannot persist zoom level after navigation with webFrame', (done) => {
      let initialNavigation = true;
      const source = `
        const {ipcRenderer, webFrame} = require('electron')
        webFrame.setZoomLevel(0.6)
        ipcRenderer.send('zoom-level-set', webFrame.getZoomLevel())
      `;
      w.webContents.on('did-finish-load', () => {
        if (initialNavigation) {
          w.webContents.executeJavaScript(source);
        } else {
          const zoomLevel = w.webContents.zoomLevel;
          expect(zoomLevel).to.equal(0);
          done();
        }
      });
      ipcMain.once('zoom-level-set', (e, zoomLevel) => {
        expect(zoomLevel).to.equal(0.6);
        w.loadFile(path.join(fixtures, 'pages', 'd.html'));
        initialNavigation = false;
      });
      w.loadFile(path.join(fixtures, 'pages', 'c.html'));
    });
  });

  describe('webrtc ip policy api', () => {
    it('can set and get webrtc ip policies', () => {
      const policies = [
        'default',
        'default_public_interface_only',
        'default_public_and_private_interfaces',
        'disable_non_proxied_udp'
      ];
      policies.forEach((policy) => {
        w.webContents.setWebRTCIPHandlingPolicy(policy);
        expect(w.webContents.getWebRTCIPHandlingPolicy()).to.equal(policy);
      });
    });
  });

  describe('render view deleted events', () => {
    let server = null;

    before((done) => {
      server = http.createServer((req, res) => {
        const respond = () => {
          if (req.url === '/redirect-cross-site') {
            res.setHeader('Location', `${server.cross_site_url}/redirected`);
            res.statusCode = 302;
            res.end();
          } else if (req.url === '/redirected') {
            res.end('<html><script>window.localStorage</script></html>');
          } else {
            res.end();
          }
        };
        setTimeout(respond, 0);
      });
      server.listen(0, '127.0.0.1', () => {
        server.url = `http://127.0.0.1:${server.address().port}`;
        server.cross_site_url = `http://localhost:${server.address().port}`;
        done();
      });
    });

    after(() => {
      server.close();
      server = null;
    });

    it('does not emit current-render-view-deleted when speculative RVHs are deleted', (done) => {
      let currentRenderViewDeletedEmitted = false;
      w.webContents.once('destroyed', () => {
        expect(currentRenderViewDeletedEmitted).to.be.false('current-render-view-deleted was emitted');
        done();
      });
      const renderViewDeletedHandler = () => {
        currentRenderViewDeletedEmitted = true;
      };
      w.webContents.on('current-render-view-deleted', renderViewDeletedHandler);
      w.webContents.on('did-finish-load', (e) => {
        w.webContents.removeListener('current-render-view-deleted', renderViewDeletedHandler);
        w.close();
      });
      w.loadURL(`${server.url}/redirect-cross-site`);
    });

    it('emits current-render-view-deleted if the current RVHs are deleted', (done) => {
      let currentRenderViewDeletedEmitted = false;
      w.webContents.once('destroyed', () => {
        expect(currentRenderViewDeletedEmitted).to.be.true('current-render-view-deleted wasn\'t emitted');
        done();
      });
      w.webContents.on('current-render-view-deleted', () => {
        currentRenderViewDeletedEmitted = true;
      });
      w.webContents.on('did-finish-load', (e) => {
        w.close();
      });
      w.loadURL(`${server.url}/redirect-cross-site`);
    });

    it('emits render-view-deleted if any RVHs are deleted', (done) => {
      let rvhDeletedCount = 0;
      w.webContents.once('destroyed', () => {
        const expectedRenderViewDeletedEventCount = 3; // 1 speculative upon redirection + 2 upon window close.
        expect(rvhDeletedCount).to.equal(expectedRenderViewDeletedEventCount, 'render-view-deleted wasn\'t emitted the expected nr. of times');
        done();
      });
      w.webContents.on('render-view-deleted', () => {
        rvhDeletedCount++;
      });
      w.webContents.on('did-finish-load', (e) => {
        w.close();
      });
      w.loadURL(`${server.url}/redirect-cross-site`);
    });
  });

  describe('setIgnoreMenuShortcuts(ignore)', () => {
    it('does not throw', () => {
      expect(() => {
        w.webContents.setIgnoreMenuShortcuts(true);
        w.webContents.setIgnoreMenuShortcuts(false);
      }).to.not.throw();
    });
  });

  describe('create()', () => {
    it('does not crash on exit', async () => {
      const appPath = path.join(__dirname, 'fixtures', 'api', 'leak-exit-webcontents.js');
      const electronPath = remote.getGlobal('process').execPath;
      const appProcess = ChildProcess.spawn(electronPath, [appPath]);
      const [code] = await emittedOnce(appProcess, 'close');
      expect(code).to.equal(0);
    });
  });

  // Destroying webContents in its event listener is going to crash when
  // Electron is built in Debug mode.
  xdescribe('destroy()', () => {
    let server;

    before((done) => {
      server = http.createServer((request, response) => {
        switch (request.url) {
          case '/404':
            response.statusCode = '404';
            response.end();
            break;
          case '/301':
            response.statusCode = '301';
            response.setHeader('Location', '/200');
            response.end();
            break;
          case '/200':
            response.statusCode = '200';
            response.end('hello');
            break;
          default:
            done('unsupported endpoint');
        }
      }).listen(0, '127.0.0.1', () => {
        server.url = 'http://127.0.0.1:' + server.address().port;
        done();
      });
    });

    after(() => {
      server.close();
      server = null;
    });

    it('should not crash when invoked synchronously inside navigation observer', (done) => {
      const events = [
        { name: 'did-start-loading', url: `${server.url}/200` },
        { name: 'dom-ready', url: `${server.url}/200` },
        { name: 'did-stop-loading', url: `${server.url}/200` },
        { name: 'did-finish-load', url: `${server.url}/200` },
        // FIXME: Multiple Emit calls inside an observer assume that object
        // will be alive till end of the observer. Synchronous `destroy` api
        // violates this contract and crashes.
        // { name: 'did-frame-finish-load', url: `${server.url}/200` },
        { name: 'did-fail-load', url: `${server.url}/404` }
      ];
      const responseEvent = 'webcontents-destroyed';

      function * genNavigationEvent () {
        let eventOptions = null;
        while ((eventOptions = events.shift()) && events.length) {
          eventOptions.responseEvent = responseEvent;
          ipcRenderer.send('test-webcontents-navigation-observer', eventOptions);
          yield 1;
        }
      }

      const gen = genNavigationEvent();
      ipcRenderer.on(responseEvent, () => {
        if (!gen.next().value) done();
      });
      gen.next();
    });
  });

  describe('did-change-theme-color event', () => {
    it('is triggered with correct theme color', (done) => {
      let count = 0;
      w.webContents.on('did-change-theme-color', (e, color) => {
        if (count === 0) {
          count += 1;
          expect(color).to.equal('#FFEEDD');
          w.loadFile(path.join(fixtures, 'pages', 'base-page.html'));
        } else if (count === 1) {
          expect(color).to.be.null();
          done();
        }
      });
      w.loadFile(path.join(fixtures, 'pages', 'theme-color.html'));
    });
  });

  describe('console-message event', () => {
    it('is triggered with correct log message', (done) => {
      w.webContents.on('console-message', (e, level, message) => {
        // Don't just assert as Chromium might emit other logs that we should ignore.
        if (message === 'a') {
          done();
        }
      });
      w.loadFile(path.join(fixtures, 'pages', 'a.html'));
    });
  });

  describe('ipc-message event', () => {
    it('emits when the renderer process sends an asynchronous message', async () => {
      const webContents = remote.getCurrentWebContents();
      const promise = emittedOnce(webContents, 'ipc-message');

      ipcRenderer.send('message', 'Hello World!');

      const [, channel, message] = await promise;
      expect(channel).to.equal('message');
      expect(message).to.equal('Hello World!');
    });
  });

  describe('ipc-message-sync event', () => {
    it('emits when the renderer process sends a synchronous message', async () => {
      const webContents = remote.getCurrentWebContents();
      const promise = emittedOnce(webContents, 'ipc-message-sync');

      ipcRenderer.send('handle-next-ipc-message-sync', 'foobar');
      const result = ipcRenderer.sendSync('message', 'Hello World!');

      const [, channel, message] = await promise;
      expect(channel).to.equal('message');
      expect(message).to.equal('Hello World!');
      expect(result).to.equal('foobar');
    });
  });

  describe('referrer', () => {
    it('propagates referrer information to new target=_blank windows', (done) => {
      const server = http.createServer((req, res) => {
        if (req.url === '/should_have_referrer') {
          expect(req.headers.referer).to.equal(`http://127.0.0.1:${server.address().port}/`);
          return done();
        }
        res.end('<a id="a" href="/should_have_referrer" target="_blank">link</a>');
      });
      server.listen(0, '127.0.0.1', () => {
        const url = 'http://127.0.0.1:' + server.address().port + '/';
        w.webContents.once('did-finish-load', () => {
          w.webContents.once('new-window', (event, newUrl, frameName, disposition, options, features, referrer) => {
            expect(referrer.url).to.equal(url);
            expect(referrer.policy).to.equal('no-referrer-when-downgrade');
          });
          w.webContents.executeJavaScript('a.click()');
        });
        w.loadURL(url);
      });
    });

    // TODO(jeremy): window.open() in a real browser passes the referrer, but
    // our hacked-up window.open() shim doesn't. It should.
    xit('propagates referrer information to windows opened with window.open', (done) => {
      const server = http.createServer((req, res) => {
        if (req.url === '/should_have_referrer') {
          expect(req.headers.referer).to.equal(`http://127.0.0.1:${server.address().port}/`);
          return done();
        }
        res.end('');
      });
      server.listen(0, '127.0.0.1', () => {
        const url = 'http://127.0.0.1:' + server.address().port + '/';
        w.webContents.once('did-finish-load', () => {
          w.webContents.once('new-window', (event, newUrl, frameName, disposition, options, features, referrer) => {
            expect(referrer.url).to.equal(url);
            expect(referrer.policy).to.equal('no-referrer-when-downgrade');
          });
          w.webContents.executeJavaScript('window.open(location.href + "should_have_referrer")');
        });
        w.loadURL(url);
      });
    });
  });

  describe('webframe messages in sandboxed contents', () => {
    it('responds to executeJavaScript', async () => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });
      await w.loadURL('about:blank');
      const result = await w.webContents.executeJavaScript('37 + 5');
      expect(result).to.equal(42);
    });
  });

  describe('preload-error event', () => {
    const generateSpecs = (description, sandbox) => {
      describe(description, () => {
        it('is triggered when unhandled exception is thrown', async () => {
          const preload = path.join(fixtures, 'module', 'preload-error-exception.js');

          w.destroy();
          w = new BrowserWindow({
            show: false,
            webPreferences: {
              sandbox,
              preload
            }
          });

          const promise = emittedOnce(w.webContents, 'preload-error');
          w.loadURL('about:blank');

          const [, preloadPath, error] = await promise;
          expect(preloadPath).to.equal(preload);
          expect(error.message).to.equal('Hello World!');
        });

        it('is triggered on syntax errors', async () => {
          const preload = path.join(fixtures, 'module', 'preload-error-syntax.js');

          w.destroy();
          w = new BrowserWindow({
            show: false,
            webPreferences: {
              sandbox,
              preload
            }
          });

          const promise = emittedOnce(w.webContents, 'preload-error');
          w.loadURL('about:blank');

          const [, preloadPath, error] = await promise;
          expect(preloadPath).to.equal(preload);
          expect(error.message).to.equal('foobar is not defined');
        });

        it('is triggered when preload script loading fails', async () => {
          const preload = path.join(fixtures, 'module', 'preload-invalid.js');

          w.destroy();
          w = new BrowserWindow({
            show: false,
            webPreferences: {
              sandbox,
              preload
            }
          });

          const promise = emittedOnce(w.webContents, 'preload-error');
          w.loadURL('about:blank');

          const [, preloadPath, error] = await promise;
          expect(preloadPath).to.equal(preload);
          expect(error.message).to.contain('preload-invalid.js');
        });
      });
    };

    generateSpecs('without sandbox', false);
    generateSpecs('with sandbox', true);
  });

  describe('takeHeapSnapshot()', () => {
    it('works with sandboxed renderers', async () => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });

      await w.loadURL('about:blank');

      const filePath = path.join(remote.app.getPath('temp'), 'test.heapsnapshot');

      const cleanup = () => {
        try {
          fs.unlinkSync(filePath);
        } catch (e) {
          // ignore error
        }
      };

      try {
        await w.webContents.takeHeapSnapshot(filePath);
        const stats = fs.statSync(filePath);
        expect(stats.size).not.to.be.equal(0);
      } finally {
        cleanup();
      }
    });

    it('fails with invalid file path', async () => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });

      await w.loadURL('about:blank');

      const promise = w.webContents.takeHeapSnapshot('');
      return expect(promise).to.be.eventually.rejectedWith(Error, 'takeHeapSnapshot failed');
    });
  });

  describe('setBackgroundThrottling()', () => {
    it('does not crash when allowing', (done) => {
      w.webContents.setBackgroundThrottling(true);
      done();
    });

    it('does not crash when disallowing', (done) => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        width: 400,
        height: 400,
        webPreferences: {
          backgroundThrottling: true
        }
      });

      w.webContents.setBackgroundThrottling(false);
      done();
    });

    it('does not crash when called via BrowserWindow', (done) => {
      w.setBackgroundThrottling(true);
      done();
    });
  });

  describe('getPrinterList()', () => {
    before(function () {
      if (!features.isPrintingEnabled()) {
        return closeWindow(w).then(() => {
          w = null;
          this.skip();
        });
      }
    });

    it('can get printer list', async () => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });
      await w.loadURL('data:text/html,%3Ch1%3EHello%2C%20World!%3C%2Fh1%3E');
      const printers = w.webContents.getPrinters();
      expect(printers).to.be.an('array');
    });
  });

  describe('printToPDF()', () => {
    before(function () {
      if (!features.isPrintingEnabled()) {
        return closeWindow(w).then(() => {
          w = null;
          this.skip();
        });
      }
    });

    it('can print to PDF', async () => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });
      await w.loadURL('data:text/html,%3Ch1%3EHello%2C%20World!%3C%2Fh1%3E');
      const data = await w.webContents.printToPDF({});
      expect(data).to.be.an.instanceof(Buffer).that.is.not.empty();
    });

    it('does not crash when called multiple times', async () => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });
      await w.loadURL('data:text/html,%3Ch1%3EHello%2C%20World!%3C%2Fh1%3E');
      const promises = [];
      for (let i = 0; i < 2; i++) {
        promises.push(w.webContents.printToPDF({}));
      }
      const results = await Promise.all(promises);
      for (const data of results) {
        expect(data).to.be.an.instanceof(Buffer).that.is.not.empty();
      }
    });
  });

  describe('PictureInPicture video', () => {
    it('works as expected', (done) => {
      w.destroy();
      w = new BrowserWindow({
        show: false,
        webPreferences: {
          sandbox: true
        }
      });
      w.webContents.once('did-finish-load', async () => {
        const result = await w.webContents.executeJavaScript(
          `runTest(${features.isPictureInPictureEnabled()})`, true);
        expect(result).to.be.true();
        done();
      });
      w.loadFile(path.join(fixtures, 'api', 'picture-in-picture.html'));
    });
  });
});