Module: Percy

Defined in:
lib/percy.rb,
lib/version.rb

Constant Summary collapse

CLIENT_INFO = 
"percy-selenium-ruby/#{VERSION}".freeze
ENV_INFO = 
"selenium/#{Selenium::WebDriver::VERSION} ruby/#{RUBY_VERSION}".freeze
SESSION_TYPE_AUTOMATE = 
'automate'.freeze
SESSION_TYPE_WEB = 
'web'.freeze
PERCY_DEBUG = 
ENV['PERCY_LOGLEVEL'] == 'debug'
PERCY_SERVER_ADDRESS = 
ENV['PERCY_SERVER_ADDRESS'] || 'http://localhost:5338'
LABEL = 
"[\u001b[35m" + (PERCY_DEBUG ? 'percy:ruby' : 'percy') + "\u001b[39m]"
RESPONSIVE_CAPTURE_SLEEP_TIME = 
ENV['RESPONSIVE_CAPTURE_SLEEP_TIME'] ||
ENV['RESONSIVE_CAPTURE_SLEEP_TIME']
VERSION = 
'1.1.4-beta.1'.freeze

Class Method Summary collapse

Class Method Details

._clear_cache! ⇒ Object 



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# File 'lib/percy.rb', line 578

def self._clear_cache!
  @percy_dom = nil
  @percy_enabled = nil
  @cli_config = nil
  @session_type = nil
  Cache.clear_cache!
end

.capture_responsive_dom(driver, options, percy_dom_script: nil) ⇒ Object 



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# File 'lib/percy.rb', line 369

def self.capture_responsive_dom(driver, options, percy_dom_script: nil)
  widths = get_responsive_widths(options[:widths] || [])
  dom_snapshots = []
  window_size = get_browser_instance(driver).window.size
  current_width = window_size.width
  current_height = window_size.height
  last_window_width = current_width
  last_window_height = current_height
  resize_count = 0
  driver.execute_script('PercyDOM.waitForResize()')
  target_height = current_height

  if responsive_capture_min_height?
    min = options[:minHeight] || @cli_config&.dig('snapshot', 'minHeight')
    if min
      target_height = min
    else
      log('PERCY_RESPONSIVE_CAPTURE_MIN_HEIGHT is enabled but no minHeight value ' \
          'was provided in options or CLI config; using current window height', 'debug',)
    end
  end

  begin
    widths.each do |width_dict|
      width = width_dict['width']
      height = width_dict['height'] || target_height

      if last_window_width != width || last_window_height != height
        resize_count += 1
        change_window_dimension_and_wait(driver, width, height, resize_count)
        last_window_width = width
        last_window_height = height
      end

      if responsive_capture_reload_page?
        log("Reloading page for width: #{width}", 'debug')
        begin
          driver.navigate.refresh
        rescue StandardError
          begin
            driver.driver.browser.navigate.refresh
          rescue StandardError => e
            log("Failed to refresh page: #{e}", 'debug')
          end
        end
        percy_dom_script = fetch_percy_dom
        driver.execute_script(percy_dom_script)
        driver.execute_script('PercyDOM.waitForResize()')
        resize_count = 0
      end

      sleep(RESPONSIVE_CAPTURE_SLEEP_TIME.to_i) if RESPONSIVE_CAPTURE_SLEEP_TIME

      dom_snapshot = get_serialized_dom(driver, options, percy_dom_script: percy_dom_script)
      dom_snapshot['width'] = width
      dom_snapshots << dom_snapshot
    end
  ensure
    change_window_dimension_and_wait(driver, current_width, current_height, resize_count + 1)
  end

  dom_snapshots
end

.change_window_dimension_and_wait(driver, width, height, resize_count) ⇒ Object 



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# File 'lib/percy.rb', line 341

def self.change_window_dimension_and_wait(driver, width, height, resize_count)
  log("Attempting to resize window to #{width}x#{height}", 'debug')

  begin
    if driver.capabilities.browser_name == 'chrome' && driver.respond_to?(:execute_cdp)
      driver.execute_cdp('Emulation.setDeviceMetricsOverride', {
                           height: height, width: width, deviceScaleFactor: 1, mobile: false,
                         },)
    else
      get_browser_instance(driver).window.resize_to(width, height)
      driver.execute_script("window.dispatchEvent(new Event('resize'));")
    end
  rescue StandardError => e
    log("Resizing using cdp failed, falling back to driver for width #{width} #{e}", 'debug')
    get_browser_instance(driver).window.resize_to(width, height)
    driver.execute_script("window.dispatchEvent(new Event('resize'));")
  end

  begin
    wait = Selenium::WebDriver::Wait.new(timeout: 1)
    wait.until { driver.execute_script('return window.resizeCount') == resize_count }
    actual_size = driver.execute_script('return { w: window.innerWidth, h: window.innerHeight }')
    log("Resize successful. New Viewport Size: #{actual_size['w']}x#{actual_size['h']}", 'debug')
  rescue Selenium::WebDriver::Error::TimeoutError
    log("Timed out waiting for window resize event for width #{width}", 'debug')
  end
end

.create_region(bounding_box: nil, element_xpath: nil, element_css: nil, padding: nil, algorithm: 'ignore', diff_sensitivity: nil, image_ignore_threshold: nil, carousels_enabled: nil, banners_enabled: nil, ads_enabled: nil, diff_ignore_threshold: nil) ⇒ Object 



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# File 'lib/percy.rb', line 33

def self.create_region(
  bounding_box: nil, element_xpath: nil, element_css: nil, padding: nil,
  algorithm: 'ignore', diff_sensitivity: nil, image_ignore_threshold: nil,
  carousels_enabled: nil, banners_enabled: nil, ads_enabled: nil, diff_ignore_threshold: nil
)
  element_selector = {}
  element_selector[:boundingBox] = bounding_box if bounding_box
  element_selector[:elementXpath] = element_xpath if element_xpath
  element_selector[:elementCSS] = element_css if element_css

  region = {
    algorithm: algorithm,
    elementSelector: element_selector,
  }

  region[:padding] = padding if padding

  if %w[standard intelliignore].include?(algorithm)
    configuration = {
      diffSensitivity: diff_sensitivity,
      imageIgnoreThreshold: image_ignore_threshold,
      carouselsEnabled: carousels_enabled,
      bannersEnabled: banners_enabled,
      adsEnabled: ads_enabled,
    }.compact

    region[:configuration] = configuration unless configuration.empty?
  end

  assertion = {}
  assertion[:diffIgnoreThreshold] = diff_ignore_threshold unless diff_ignore_threshold.nil?
  region[:assertion] = assertion unless assertion.empty?

  region
end

.deep_merge_options(base, override) ⇒ Object

Deep-merge override onto base: nested Hashes merge recursively, while arrays and scalars from override replace those in base.



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# File 'lib/percy.rb', line 82

def self.deep_merge_options(base, override)
  base.merge(override) do |_key, old_val, new_val|
    old_val.is_a?(Hash) && new_val.is_a?(Hash) ? deep_merge_options(old_val, new_val) : new_val
  end
end

.deep_symbolize(obj) ⇒ Object

Recursively convert all Hash keys (at every nesting level) to symbols so config (string keys from JSON) and per-call options (symbol keys) merge on consistent keys. Arrays are walked; scalars are returned as-is.



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# File 'lib/percy.rb', line 72

def self.deep_symbolize(obj)
  case obj
  when Hash then obj.each_with_object({}) { |(k, v), h| h[k.to_sym] = deep_symbolize(v) }
  when Array then obj.map { |e| deep_symbolize(e) }
  else obj
  end
end

.fetch(url, data = nil) ⇒ Object 



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# File 'lib/percy.rb', line 498

def self.fetch(url, data = nil)
  uri = URI("#{PERCY_SERVER_ADDRESS}/#{url}")

  response = if data
    http = Net::HTTP.new(uri.host, uri.port)
    http.read_timeout = 600 # seconds
    request = Net::HTTP::Post.new(uri.path)
    request.body = data.to_json
    http.request(request)
  else
    Net::HTTP.get_response(uri)
  end

  unless response.is_a? Net::HTTPSuccess
    raise StandardError, "Failed with HTTP error code: #{response.code}"
  end

  response
end

.fetch_percy_dom ⇒ Object 



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# File 'lib/percy.rb', line 476

def self.fetch_percy_dom
  return @percy_dom unless @percy_dom.nil?

  response = fetch('percy/dom.js')
  @percy_dom = response.body
end

.get_browser_instance(driver) ⇒ Object 



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# File 'lib/percy.rb', line 140

def self.get_browser_instance(driver)
  if driver.respond_to?(:driver) && driver.driver.respond_to?(:browser)
    return driver.driver.browser.manage
  end

  driver.manage
end

.get_driver_metadata(driver) ⇒ Object 



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# File 'lib/percy.rb', line 570

def self.get_driver_metadata(driver)
  DriverMetaData.new(driver)
end

.get_element_ids(elements) ⇒ Object 



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# File 'lib/percy.rb', line 574

def self.get_element_ids(elements)
  elements.map(&:id)
end

.get_origin(url) ⇒ Object

Raises:

  • (URI::InvalidURIError) 


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# File 'lib/percy.rb', line 262

def self.get_origin(url)
  uri = URI.parse(url)
  raise URI::InvalidURIError, "no host in #{url}" if uri.host.nil?

  netloc = uri.host.to_s
  default_ports = {'http' => 80, 'https' => 443}
  netloc += ":#{uri.port}" if uri.port && uri.port != default_ports[uri.scheme]
  "#{uri.scheme}://#{netloc}"
end

.get_responsive_widths(widths = []) ⇒ Object 



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# File 'lib/percy.rb', line 321

def self.get_responsive_widths(widths = [])
  begin
    widths_list = widths.is_a?(Array) ? widths : []
    query_param = widths_list.any? ? "?widths=#{widths_list.join(',')}" : ''
    response = fetch("percy/widths-config#{query_param}")
    data = JSON.parse(response.body)
    widths_data = data['widths']
    unless widths_data.is_a?(Array)
      msg = 'Update Percy CLI to the latest version to use responsiveSnapshotCapture'
      raise StandardError, msg
    end

    widths_data
  rescue StandardError => e
    log("Failed to get responsive widths: #{e}.", 'debug')
    raise StandardError, 'Update Percy CLI to the latest version to use ' \
      'responsiveSnapshotCapture'
  end
end

.get_serialized_dom(driver, options, percy_dom_script: nil) ⇒ Object 



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# File 'lib/percy.rb', line 209

def self.get_serialized_dom(driver, options, percy_dom_script: nil)
  # Readiness gate before serialize. Graceful on old CLI.
  readiness_diagnostics = wait_for_ready(driver, options)
  # Strip `readiness` from forwarded serialize args -- it's consumed by
  # wait_for_ready upstream, not a PercyDOM.serialize argument.
  serialize_options = options.reject { |k, _| k.to_s == 'readiness' }
  dom_snapshot = driver.execute_script("return PercyDOM.serialize(#{serialize_options.to_json})")
  # `!nil?` preserves legitimate falsy returns like {} ("gate ran, no
  # notable diagnostics").
  if !readiness_diagnostics.nil? && dom_snapshot.is_a?(Hash)
    dom_snapshot['readiness_diagnostics'] = readiness_diagnostics
  end
  begin
    page_origin = get_origin(driver.current_url)
    iframes = percy_dom_script ? driver.find_elements(:tag_name, 'iframe') : []
    if iframes.any?
      processed_frames = []
      iframes.each do |frame|
        frame_src = frame.attribute('src')
        next if unsupported_iframe_src?(frame_src)

        begin
          frame_origin = get_origin(URI.join(driver.current_url, frame_src).to_s)
        rescue StandardError => e
          log("Skipping iframe \"#{frame_src}\": #{e}", 'debug')
          next
        end

        next if frame_origin == page_origin

        result = process_frame(driver, frame, options, percy_dom_script)
        processed_frames << result if result
      end
      dom_snapshot['corsIframes'] = processed_frames if processed_frames.any?
    end
  rescue StandardError => e
    log("Failed to process cross-origin iframes: #{e}", 'debug')
    begin
      driver.switch_to.default_content
    rescue StandardError
      nil
    end
  end

  dom_snapshot['cookies'] = get_browser_instance(driver).all_cookies
  dom_snapshot
end

.log(msg, lvl = 'info') ⇒ Object 



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# File 'lib/percy.rb', line 483

def self.log(msg, lvl = 'info')
  msg = "#{LABEL} #{msg}"
  begin
    fetch('percy/log', {message: msg, level: lvl})
  rescue StandardError => e
    if PERCY_DEBUG
      puts "Sending log to CLI Failed #{e}"
    end
  ensure
    if lvl != 'debug' || PERCY_DEBUG
      puts msg
    end
  end
end

.percy_enabled? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/percy.rb', line 441

def self.percy_enabled?
  return @percy_enabled unless @percy_enabled.nil?

  begin
    response = fetch('percy/healthcheck')
    version = response['x-percy-core-version']

    if version.nil?
      log('You may be using @percy/agent ' \
          'which is no longer supported by this SDK. ' \
          'Please uninstall @percy/agent and install @percy/cli instead. ' \
          'https://www.browserstack.com/docs/percy/migration/migrate-to-cli')
      @percy_enabled = false
      return false
    end

    if version.split('.')[0] != '1'
      log("Unsupported Percy CLI version, #{version}")
      @percy_enabled = false
      return false
    end

    response_body = JSON.parse(response.body)
    @cli_config = response_body['config']
    @session_type = response_body['type']
    @percy_enabled = true
    true
  rescue StandardError => e
    log('Percy is not running, disabling snapshots')
    log(e, 'debug')
    @percy_enabled = false
    false
  end
end

.percy_screenshot(driver, name, options = {}) ⇒ Object 



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# File 'lib/percy.rb', line 518

def self.percy_screenshot(driver, name, options = {})
  return unless percy_enabled?

  unless @session_type == SESSION_TYPE_AUTOMATE
    raise StandardError, 'Invalid function call - percy_screenshot(). ' \
      'Please use percy_snapshot() function for taking screenshot. ' \
      'percy_screenshot() should be used only while using Percy with Automate. ' \
      'For more information on usage of percy_snapshot(), ' \
      'refer doc for your language https://www.browserstack.com/docs/percy/integrate/overview'
  end

  begin
    options = options.dup
    metadata = get_driver_metadata(driver)

    if options.key?(:ignoreRegionSeleniumElements)
      options[:ignore_region_selenium_elements] = options.delete(:ignoreRegionSeleniumElements)
    end
    if options.key?(:considerRegionSeleniumElements)
      options[:consider_region_selenium_elements] =
        options.delete(:considerRegionSeleniumElements)
    end

    ignore_region_elements =
      get_element_ids(options.delete(:ignore_region_selenium_elements) || [])
    consider_region_elements =
      get_element_ids(options.delete(:consider_region_selenium_elements) || [])

    options[:ignore_region_elements] = ignore_region_elements
    options[:consider_region_elements] = consider_region_elements

    response = fetch('percy/automateScreenshot',
      client_info: CLIENT_INFO,
      environment_info: ENV_INFO,
      sessionId: metadata.session_id,
      commandExecutorUrl: metadata.command_executor_url,
      capabilities: metadata.capabilities,
      snapshotName: name,
      options: options,)

    body = JSON.parse(response.body)
    unless body['success']
      raise StandardError, body['error']
    end

    body['data']
  rescue StandardError => e
    log("Could not take Screenshot '#{name}'")
    log(e, 'debug')
  end
end

.process_frame(driver, frame_element, options, percy_dom_script) ⇒ Object 



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# File 'lib/percy.rb', line 272

def self.process_frame(driver, frame_element, options, percy_dom_script)
  frame_url = frame_element.attribute('src') || 'unknown-src'
  iframe_snapshot = nil

  begin
    driver.switch_to.frame(frame_element)
    begin
      driver.execute_script(percy_dom_script)
      iframe_options = options.merge('enableJavaScript' => true)
      iframe_snapshot =
        driver.execute_script("return PercyDOM.serialize(#{iframe_options.to_json})")
    rescue StandardError => e
      log("Failed to process cross-origin frame #{frame_url}: #{e}", 'debug')
    ensure
      begin
        driver.switch_to.default_content
      rescue StandardError
        begin
          driver.switch_to.parent_frame
        rescue StandardError
          nil
        end
      end
    end
  rescue StandardError => e
    log("Failed to switch to frame #{frame_url}: #{e}", 'debug')
    begin
      driver.switch_to.default_content
    rescue StandardError
      nil
    end
    return nil
  end

  return nil if iframe_snapshot.nil?

  percy_element_id = frame_element.attribute('data-percy-element-id')
  unless percy_element_id
    log("Skipping frame #{frame_url}: no matching percyElementId found", 'debug')
    return nil
  end

  {
    'iframeData' => {'percyElementId' => percy_element_id},
    'iframeSnapshot' => iframe_snapshot,
    'frameUrl' => frame_url,
  }
end

.resolve_readiness_config(options) ⇒ Object

Shallow-merge of global (@cli_config.snapshot.readiness) and per-snapshot (options / options) readiness config. Per-snapshot keys win, unspecified global keys (notably preset: disabled) are inherited.



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# File 'lib/percy.rb', line 151

def self.resolve_readiness_config(options)
  global = @cli_config&.dig('snapshot', 'readiness')
  global = {} unless global.is_a?(Hash)
  per_snapshot = options[:readiness] || options['readiness']
  per_snapshot = {} unless per_snapshot.is_a?(Hash)
  # Normalise symbol keys to strings so the merge collapses :preset and 'preset'.
  [global, per_snapshot].each_with_object({}) do |hash, merged|
    hash.each { |k, v| merged[k.to_s] = v }
  end
end

.responsive_capture_min_height? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/percy.rb', line 27

def self.responsive_capture_min_height?
  val = ENV['PERCY_RESPONSIVE_CAPTURE_MIN_HEIGHT'] ||
    ENV['PERCY_RESONSIVE_CAPTURE_MIN_HEIGHT'] || 'false'
  val.casecmp('true') == 0
end

.responsive_capture_reload_page? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/percy.rb', line 21

def self.responsive_capture_reload_page?
  val = ENV['PERCY_RESPONSIVE_CAPTURE_RELOAD_PAGE'] ||
    ENV['PERCY_RESONSIVE_CAPTURE_RELOAD_PAGE'] || 'false'
  val.casecmp('true') == 0
end

.responsive_snapshot_capture?(options) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/percy.rb', line 433

def self.responsive_snapshot_capture?(options)
  return false if @cli_config&.dig('percy', 'deferUploads')

  options[:responsive_snapshot_capture] ||
    options[:responsiveSnapshotCapture] ||
    @cli_config&.dig('snapshot', 'responsiveSnapshotCapture')
end

.snapshot(driver, name, options = {}) ⇒ Object 



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# File 'lib/percy.rb', line 88

def self.snapshot(driver, name, options = {})
  return unless percy_enabled?

  if @session_type == SESSION_TYPE_AUTOMATE
    raise StandardError, 'Invalid function call - percy_snapshot(). ' \
      'Please use percy_screenshot() function while using Percy with Automate. ' \
      'For more information on usage of percy_screenshot(), ' \
      'refer https://www.browserstack.com/docs/percy/integrate/functional-and-visual'
  end

  begin
    percy_dom_script = fetch_percy_dom
    driver.execute_script(percy_dom_script)

    # Merge .percy.yml config options with snapshot options (snapshot options take priority)
    config_options = @cli_config&.dig('snapshot') || {}
    # Config keys are strings (JSON parse); per-call options use symbols, as
    # do downstream consumers (responsive_snapshot_capture?, capture_responsive_dom).
    # Deep-symbolize both sides so nested keys are consistent, then deep-merge
    # so nested Hashes merge recursively (per-call wins at leaves; arrays/scalars
    # replace) instead of a shallow top-level overwrite dropping config siblings.
    merged_options = deep_merge_options(deep_symbolize(config_options), deep_symbolize(options))

    dom_snapshot = if responsive_snapshot_capture?(merged_options)
      capture_responsive_dom(driver, merged_options, percy_dom_script: percy_dom_script)
    else
      get_serialized_dom(driver, merged_options, percy_dom_script: percy_dom_script)
    end

    # Strip `readiness` before POSTing -- SDK-local config that the CLI
    # already has via healthcheck.
    post_options = options.reject { |k, _| k.to_s == 'readiness' }
    response = fetch('percy/snapshot',
      name: name,
      url: driver.current_url,
      dom_snapshot: dom_snapshot,
      client_info: CLIENT_INFO,
      environment_info: ENV_INFO,
      **post_options,)

    body = JSON.parse(response.body)
    unless body['success']
      raise StandardError, body['error']
    end

    body['data']
  rescue StandardError => e
    log("Could not take DOM snapshot '#{name}'")
    log(e, 'debug')
  end
end

.unsupported_iframe_src?(src) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/percy.rb', line 257

def self.unsupported_iframe_src?(src)
  src.nil? || src.empty? || src == 'about:blank' ||
    src.start_with?('javascript:') || src.start_with?('data:') || src.start_with?('vbscript:')
end

.wait_for_ready(driver, options) ⇒ Object

Readiness gate: runs PercyDOM.waitForReady via execute_async_script BEFORE serialize. Graceful on old CLIs that lack the method. Returns readiness diagnostics (or nil) for attachment to domSnapshot.



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# File 'lib/percy.rb', line 165

def self.wait_for_ready(driver, options)
  readiness_config = resolve_readiness_config(options)
  return nil if readiness_config['preset'] == 'disabled'

  # Match the driver's async-script timeout to readiness.timeoutMs so a
  # higher user-configured timeout isn't silently capped by Selenium's
  # default (~30s) firing ScriptTimeoutException before the in-page
  # Promise resolves.
  timeout_ms = readiness_config['timeoutMs']
  previous_timeout = nil
  if timeout_ms.is_a?(Numeric) && timeout_ms > 0
    begin
      previous_timeout = driver.manage.timeouts.script_timeout
      driver.manage.timeouts.script_timeout = (timeout_ms / 1000.0) + 2
    rescue StandardError
      previous_timeout = nil # best-effort; older Selenium / unsupported
    end
  end

  begin
    script = <<~JS
      var cfg = #{readiness_config.to_json};
      var done = arguments[arguments.length - 1];
      try {
        if (typeof PercyDOM !== 'undefined' && typeof PercyDOM.waitForReady === 'function') {
          PercyDOM.waitForReady(cfg).then(function(r){ done(r); }).catch(function(){ done(); });
        } else { done(); }
      } catch (e) { done(); }
    JS
    driver.execute_async_script(script)
  rescue StandardError => e
    log("waitForReady failed, proceeding to serialize: #{e}", 'debug')
    nil
  ensure
    if previous_timeout
      begin
        driver.manage.timeouts.script_timeout = previous_timeout
      rescue StandardError
        # best-effort
      end
    end
  end
end