Add webp to screenshot options

lib/puppeteer/page.rb

@@ -965,7 +965,7 @@ def title
     main_frame.title
   end
 
-  # @param type [String] "png"|"jpeg"
+  # @param type [String] "png"|"jpeg"|"webp"
   # @param path [String]
   # @param full_page [Boolean]
   # @param clip [Hash]

lib/puppeteer/page/screenshot_options.rb

@@ -15,7 +15,7 @@ class ScreenshotOptions
     # @params options [Hash]
     def initialize(options)
       if options[:type]
-        unless [:png, :jpeg].include?(options[:type].to_sym)
+        unless [:png, :jpeg, :webp].include?(options[:type].to_sym)
           raise ArgumentError.new("Unknown options.type value: #{options[:type]}")
         end
         @type = options[:type]
@@ -25,6 +25,8 @@ def initialize(options)
           @type = 'png'
         elsif mime_types.include?('image/jpeg')
           @type = 'jpeg'
+        elsif mime_types.include?('image/webp')
+          @type = 'webp'
         else
           raise ArgumentError.new("Unsupported screenshot mime type resolved: #{mime_types}, path: #{options[:path]}")
         end

spec/integration/screenshot_spec.rb

@@ -103,6 +103,16 @@
     #   });
     #   expect(screenshot).toBeGolden('white.jpg');
     # });
+
+    it_fails_firefox 'should work with webp' do
+      screenshot = page.screenshot(type: :webp)
+      expect(screenshot.length).to be >= 1000
+      Dir.mktmpdir do |tmpdir|
+        path = File.join(tmpdir, 'image.webp')
+        page.screenshot(path: path)
+      end
+    end
+
     # it('should work with odd clip size on Retina displays', async () => {
     #   const { page } = getTestState();