Refactor/remove base

CHANGELOG.md

@@ -14,6 +14,7 @@ Please visit [cucumber/CONTRIBUTING.md](https://github.com/cucumber/cucumber/blo
 
 ### Changed
 - Increased upper bounds of `cucumber-messages` to v34 and `cucumber-gherkin` to v42
+- **BREAKING CHANGE:** Event base class has been internally refactored. See upgrading notes for [19.0.0.md](upgrading_notes/19.0.0.md#upgrading-to-cucumber-core-1900), for full changes
 
 ## [18.0.0] - 2026-07-13
 ### Changed

lib/cucumber/core/event.rb

@@ -1,61 +1,10 @@
 # frozen_string_literal: true
 
-module Cucumber
-  module Core
-    class Event
-      # Macro to generate new subclasses of {Event} with attribute readers.
-      def self.new(*events)
-        # Use normal constructor for subclasses of Event
-        return super if ancestors.index(Event).positive?
-
-        Class.new(Event) do
-          # NB: We need to use metaprogramming here instead of direct variable obtainment
-          # because JRuby does not guarantee the order in which variables are defined is equivalent
-          # to the order in which they are obtainable
-          #
-          # See https://github.com/jruby/jruby/issues/7988 for more info
-          attr_reader(*events)
-
-          define_method(:initialize) do |*attributes|
-            events.zip(attributes) do |name, value|
-              instance_variable_set(:"@#{name}", value)
-            end
-          end
-        end
-      end
-
-      def to_h
-        instance_variables.to_h do |variable_name|
-          [variable_name[1..].to_sym, instance_variable_get(variable_name)]
-        end
-      end
-
-      def attributes
-        instance_variables.map { |var| instance_variable_get(var) }
-      end
-
-      def event_id
-        self.class.event_id
-      end
-
-      class << self
-        # @return [Symbol] the underscored name of the class to be used as the key in an event registry
-        def event_id
-          underscore(name.split('::').last).to_sym
-        end
-
-        private
-
-        def underscore(string)
-          string
-            .to_s
-            .gsub('::', '/')
-            .gsub(/([A-Z]+)([A-Z][a-z])/, '\1_\2')
-            .gsub(/([a-z\d])([A-Z])/, '\1_\2')
-            .tr('-', '_')
-            .downcase
-        end
-      end
-    end
-  end
-end
+require_relative 'event/envelope'
+require_relative 'event/gherkin_source_parsed'
+require_relative 'event/test_case_created'
+require_relative 'event/test_case_started'
+require_relative 'event/test_case_finished'
+require_relative 'event/test_step_created'
+require_relative 'event/test_step_started'
+require_relative 'event/test_step_finished'

lib/cucumber/core/events/base.rb → lib/cucumber/core/event/base.rb

@@ -2,7 +2,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # An archetype of what each Cucumber Event defined in cucumber-ruby must adhere to
       class Base
         # The "key" name of the class to be used as the key in the event registry (Underscored name symbolized)

lib/cucumber/core/events/envelope.rb → lib/cucumber/core/event/envelope.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       class Envelope < Base
         attr_reader :envelope
 

lib/cucumber/core/events/gherkin_source_parsed.rb → lib/cucumber/core/event/gherkin_source_parsed.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a gherkin source has been parsed
       class GherkinSourceParsed < Base
         # @return [GherkinDocument] the GherkinDocument Ast Node that was parsed

lib/cucumber/core/events/test_case_created.rb → lib/cucumber/core/event/test_case_created.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a Test::Case was created from a Pickle
       class TestCaseCreated < Base
         attr_reader :test_case, :pickle

lib/cucumber/core/events/test_case_finished.rb → lib/cucumber/core/event/test_case_finished.rb

@@ -1,10 +1,10 @@
 # frozen_string_literal: true
 
-require_relative '../event'
+require_relative 'base'
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a {Test::Case} has finished executing
       class TestCaseFinished < Base
         # @return [Test::Case] that was executed

lib/cucumber/core/events/test_case_started.rb → lib/cucumber/core/event/test_case_started.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a {Test::Case} is about to be executed
       class TestCaseStarted < Base
         # @return [Cucumber::Core::Test::Case] the test case to be executed

lib/cucumber/core/events/test_step_created.rb → lib/cucumber/core/event/test_step_created.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a Test::Step was created from a PickleStep
       class TestStepCreated < Base
         attr_reader :test_step, :pickle_step

lib/cucumber/core/events/test_step_finished.rb → lib/cucumber/core/event/test_step_finished.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a {Test::Step} has finished executing
       class TestStepFinished < Base
         # @return [Cucumber::Core::Test::Step] the test step that was executed

lib/cucumber/core/events/test_step_started.rb → lib/cucumber/core/event/test_step_started.rb

@@ -4,7 +4,7 @@
 
 module Cucumber
   module Core
-    module Events
+    module Event
       # Signals that a {Test::Step} is about to be executed
       class TestStepStarted < Base
         # @return [Cucumber::Core::Test::Step] the test step to be executed

lib/cucumber/core/event_bus.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require_relative 'events'
+require_relative 'event'
 
 module Cucumber
   module Core
@@ -11,8 +11,30 @@ module Core
     class EventBus
       attr_reader :event_types
 
+      # The registry contains all the event registered in the core, that will be used by the {EventBus} by default.
+      def self.registry
+        build_registry(
+          Event::Envelope,
+          Event::GherkinSourceParsed,
+          Event::TestCaseCreated,
+          Event::TestCaseStarted,
+          Event::TestCaseFinished,
+          Event::TestStepCreated,
+          Event::TestStepStarted,
+          Event::TestStepFinished
+        )
+      end
+
+      # Build an event registry to be passed to the {EventBus} constructor from a list of types.
+      # Each type must respond to `event_id` so that it can be added to the registry hash
+      #
+      # @return [Hash{Symbol => Class}]
+      def self.build_registry(*types)
+        types.to_h { |type| [type.event_id, type] }
+      end
+
       # @param registry [Hash{Symbol => Class}] a hash of event types to use on the bus
-      def initialize(registry = Events.registry)
+      def initialize(registry = self.class.registry)
         @event_types = registry.freeze
         @handlers = {}
         @event_queue = []

spec/cucumber/core/events/base_spec.rb → spec/cucumber/core/event/base_spec.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cucumber::Core::Events::Base do
+describe Cucumber::Core::Event::Base do
   subject(:event) { my_event_type.new(1, 2) }
 
   let(:my_event_type) do