Module: Capybara::Screenshot::Diff::Stabilization

Includes:
Os
Included in:
TestMethods
Defined in:
lib/capybara/screenshot/diff/stabilization.rb

Constant Summary collapse

IMAGE_WAIT_SCRIPT = 
<<-JS.strip_heredoc.freeze
  function pending_image() {
    var images = document.images;
    for (var i = 0; i < images.length; i++) {
      if (!images[i].complete) {
          return images[i].src;
      }
    }
    return false;
  }()
JS
HIDE_CARET_SCRIPT = 
<<~JS
  if (!document.getElementById('csdHideCaretStyle')) {
    let style = document.createElement('style');
    style.setAttribute('id', 'csdHideCaretStyle');
    document.head.appendChild(style);
    let styleSheet = style.sheet;
    styleSheet.insertRule("* { caret-color: transparent !important; }", 0);
  }
JS

Constants included from Os

Os::ON_LINUX, Os::ON_MAC, Os::ON_WINDOWS

Instance Method Summary collapse

Methods included from Os

#os_name

Instance Method Details

#notice_how_to_avoid_this ⇒ Object 



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# File 'lib/capybara/screenshot/diff/stabilization.rb', line 76

def notice_how_to_avoid_this
  unless @_csd_retina_warned
    warn "Halving retina screenshot.  " \
        'You should add "force-device-scale-factor=1" to your Chrome chromeOptions args.'
    @_csd_retina_warned = true
  end
end

#take_stable_screenshot(comparison, stability_time_limit:, wait:) ⇒ Object 



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# File 'lib/capybara/screenshot/diff/stabilization.rb', line 33

def take_stable_screenshot(comparison, stability_time_limit:, wait:)
  previous_file_name = comparison.old_file_name
  screenshot_started_at = last_image_change_at = Time.now
  clean_stabilization_images(comparison.new_file_name)

  1.step do |i|
    take_right_size_screenshot(comparison)
    if comparison.quick_equal?
      clean_stabilization_images(comparison.new_file_name)
      break
    end
    comparison.reset

    if previous_file_name
      stabilization_comparison = make_stabilization_comparison_from(
        comparison,
        comparison.new_file_name,
        previous_file_name
      )
      if stabilization_comparison.quick_equal?
        if (Time.now - last_image_change_at) > stability_time_limit
          clean_stabilization_images(comparison.new_file_name)
          break
        end
        next
      else
        last_image_change_at = Time.now
      end
    end

    previous_file_name = "#{comparison.new_file_name.chomp(".png")}" \
        "_x#{format("%02i", i)}_#{(Time.now - screenshot_started_at).round(1)}s" \
        "_#{stabilization_comparison.difference_region&.to_s&.gsub(", ", "_") || :initial}.png~"
    FileUtils.mv comparison.new_file_name, previous_file_name

    check_max_wait_time(
      comparison,
      screenshot_started_at,
      max_wait_time: max_wait_time(comparison.shift_distance_limit, wait)
    )
  end
end