Support freezing the page with Chrome

Author: twalpole

.travis.yml

@@ -117,7 +117,7 @@ matrix:
       addons:
         homebrew:
           taps: homebrew/cask-versions
-          casks: microsoft-edge-canary
+          casks: microsoft-edge-dev
       before_install:
         - wget https://msedgewebdriverstorage.blob.core.windows.net/edgewebdriver/76.0.168.0/edgedriver_mac64.zip
         - unzip edgedriver_mac64.zip -d /usr/local/bin

lib/capybara/driver/base.rb

@@ -35,6 +35,14 @@ def go_forward
     raise Capybara::NotSupportedByDriverError, 'Capybara::Driver::Base#go_forward'
   end
 
+  def freeze_page
+    raise Capybara::NotSupportedByDriverError, 'Capybara::Driver::Base#freeze_page'
+  end
+
+  def thaw_page
+    raise Capybara::NotSupportedByDriverError, 'Capybara::Driver::Base#thaw_page'
+  end
+
   def execute_script(script, *args)
     raise Capybara::NotSupportedByDriverError, 'Capybara::Driver::Base#execute_script'
   end

lib/capybara/selenium/driver.rb

@@ -45,6 +45,7 @@ def browser
         end
       end
       processed_options = options.reject { |key, _val| SPECIAL_OPTIONS.include?(key) }
+
       @browser = Selenium::WebDriver.for(options[:browser], processed_options)
 
       specialize_driver

lib/capybara/selenium/driver_specializations/chrome_driver.rb

@@ -54,6 +54,15 @@ def reset!
     execute_cdp('Storage.clearDataForOrigin', origin: '*', storageTypes: storage_types_to_clear)
   end
 
+  def freeze_page
+    bridge.http.call(:post, "session/#{bridge.session_id}/goog/page/freeze", {})
+  end
+
+  def thaw_page
+    bridge.http.call(:post, "session/#{bridge.session_id}/goog/page/resume", {})
+    evaluate_script('1==1') # Ensure page has restarted
+  end
+
 private
 
   def storage_types_to_clear

lib/capybara/spec/public/test.js

@@ -48,11 +48,13 @@ $(function() {
   });
   $('#clickable').click(function(e) {
     var link = $(this);
+    $(link).after('<a id="clickable-processing" href="#">Processing<a>');
     setTimeout(function() {
       $(link).after('<a id="has-been-clicked" href="#">Has been clicked</a>');
       $(link).after('<input type="submit" value="New Here">');
       $(link).after('<input type="text" id="new_field">');
       $('#change').remove();
+      $('#clickable-processing').remove();
     }, 1000);
     return false;
   });

lib/capybara/spec/session/driver_spec.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+Capybara::SpecHelper.spec 'Driver' do
+  context 'freeze_page', requires: %i[freeze js] do
+    it 'can pause a page' do
+      @session.visit('/with_js')
+      @session.find(:css, '#clickable').click
+      sleep 0.1
+      @session.driver.freeze_page
+
+      expect(@session).to have_css('#clickable-processing')
+      sleep 3 # Time needs to be longer than click action delay
+      expect(@session).not_to have_css('#has-been-clicked')
+      expect(@session).to have_css('#clickable-processing')
+
+      @session.driver.thaw_page
+      expect(@session).to have_css('#has-been-clicked').and(have_no_css('#clickable-processing'))
+    end
+
+    it "doesn't prevent driver JS" do
+      @session.visit('/with_js')
+      @session.find(:css, '#clickable')
+      @session.driver.freeze_page
+
+      expect(@session.evaluate_script('1==1')).to eq true
+
+      @session.driver.thaw_page
+    end
+  end
+end

spec/selenium_spec_firefox.rb

@@ -42,7 +42,7 @@ module TestSessions
   SeleniumFirefox = Capybara::Session.new(:selenium_firefox, TestApp)
 end
 
-skipped_tests = %i[response_headers status_code trigger]
+skipped_tests = %i[response_headers status_code trigger freeze]
 
 Capybara::SpecHelper.log_selenium_driver_version(Selenium::WebDriver::Firefox) if ENV['CI']
 

spec/selenium_spec_firefox_remote.rb

@@ -56,7 +56,7 @@ module TestSessions
   str if File.exist?(str)
 end
 
-skipped_tests = %i[response_headers status_code trigger download]
+skipped_tests = %i[response_headers status_code trigger download freeze]
 
 Capybara::SpecHelper.run_specs TestSessions::RemoteFirefox, FIREFOX_REMOTE_DRIVER.to_s, capybara_skip: skipped_tests do |example|
   case example.metadata[:full_description]

spec/selenium_spec_safari.rb

@@ -36,7 +36,7 @@ module TestSessions
   Safari = Capybara::Session.new(SAFARI_DRIVER, TestApp)
 end
 
-skipped_tests = %i[response_headers status_code trigger windows drag]
+skipped_tests = %i[response_headers status_code trigger windows drag freeze]
 
 Capybara::SpecHelper.log_selenium_driver_version(Selenium::WebDriver::Safari) if ENV['CI']