Replace forwardable with explicit delegation for performance

lib/rubocop/ast.rb

@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require 'parser'
-require 'forwardable'
 require 'set'
 
 require_relative 'ast/ext/range'

lib/rubocop/ast/node/mixin/collection_node.rb

@@ -4,13 +4,17 @@ module RuboCop
   module AST
     # A mixin that helps give collection nodes array polymorphism.
     module CollectionNode
-      extend Forwardable
-
       ARRAY_METHODS =
         (Array.instance_methods - Object.instance_methods - [:to_a]).freeze
       private_constant :ARRAY_METHODS
 
-      def_delegators :to_a, *ARRAY_METHODS
+      ARRAY_METHODS.each do |method|
+        class_eval(<<~RUBY, __FILE__, __LINE__ + 1)
+          def #{method}(...)    # def key?(...)
+            to_a.#{method}(...) #   to_a.key?(...)
+          end                   # end
+        RUBY
+      end
     end
   end
 end

lib/rubocop/ast/node_pattern.rb

@@ -48,7 +48,6 @@ def def_node_search(method_name, pattern_str, **keyword_defaults)
         end
       end
 
-      extend Forwardable
       include MethodDefiner
       Invalid = Class.new(StandardError)
 
@@ -72,8 +71,6 @@ def self.descend(element, &block)
 
       attr_reader :pattern, :ast, :match_code
 
-      def_delegators :@compiler, :captures, :named_parameters, :positional_parameters
-
       def initialize(str, compiler: Compiler.new)
         @pattern = str
         @ast = compiler.parser.parse(str)
@@ -82,6 +79,18 @@ def initialize(str, compiler: Compiler.new)
         @cache = {}
       end
 
+      def captures
+        @compiler.captures
+      end
+
+      def named_parameters
+        @compiler.named_parameters
+      end
+
+      def positional_parameters
+        @compiler.positional_parameters
+      end
+
       def match(*args, **rest, &block)
         @cache[:lambda] ||= as_lambda
         @cache[:lambda].call(*args, block: block, **rest)

lib/rubocop/ast/node_pattern/compiler.rb

@@ -9,7 +9,6 @@ class NodePattern
       # Doc on how this fits in the compiling process:
       #   /docs/modules/ROOT/pages/node_pattern.adoc
       class Compiler
-        extend Forwardable
         attr_reader :captures, :named_parameters, :positional_parameters, :binding
 
         def initialize
@@ -21,7 +20,9 @@ def initialize
           @atom_subcompiler = self.class::AtomSubcompiler.new(self)
         end
 
-        def_delegators :binding, :bind
+        def bind(...)
+          @binding.bind(...)
+        end
 
         def positional_parameter(number)
           @positional_parameters = number if number > @positional_parameters

lib/rubocop/ast/node_pattern/compiler/debug.rb

@@ -133,7 +133,13 @@ def parser
             @parser ||= Parser::WithMeta.new
           end
 
-          def_delegators :parser, :comments, :tokens
+          def comments
+            parser.comments
+          end
+
+          def tokens
+            parser.tokens
+          end
 
           # @api private
           module InstrumentationSubcompiler

lib/rubocop/ast/node_pattern/node.rb

@@ -5,7 +5,6 @@ module AST
     class NodePattern
       # Base class for AST Nodes of a `NodePattern`
       class Node < ::Parser::AST::Node
-        extend Forwardable
         include ::RuboCop::AST::Descendence
 
         MATCHES_WITHIN_SET = %i[symbol number string].to_set.freeze
@@ -95,7 +94,13 @@ def in_sequence_head
         # Node class for `$something`
         class Capture < Node
           # Delegate most introspection methods to it's only child
-          def_delegators :child, :arity, :rest?
+          def arity
+            child.arity
+          end
+
+          def rest?
+            child.rest?
+          end
 
           def capture?
             true

lib/rubocop/ast/node_pattern/parser.rb

@@ -11,8 +11,6 @@ class NodePattern
       # Doc on how this fits in the compiling process:
       #   /docs/modules/ROOT/pages/node_pattern.adoc
       class Parser < Racc::Parser
-        extend Forwardable
-
         Builder = NodePattern::Builder
         Lexer = NodePattern::Lexer
 
@@ -43,9 +41,17 @@ def inspect
 
         private
 
-        def_delegators :@builder, :emit_list, :emit_unary_op, :emit_atom, :emit_capture,
-                       :emit_call, :emit_union
-        def_delegators :@lexer, :next_token
+        %i[emit_list emit_unary_op emit_atom emit_capture emit_call emit_union].each do |method|
+          class_eval(<<~RUBY, __FILE__, __LINE__ + 1)
+            def #{method}(...)        # def emit_list(...)
+              @builder.#{method}(...) #   @builder.emit_list(...)
+            end                       # end
+          RUBY
+        end
+
+        def next_token
+          @lexer.next_token
+        end
 
         def enforce_unary(node)
           return node if node.arity == 1