1 files changed, 33 insertions, 27 deletions

diff --git a/activerecord/lib/active_record/associations/builder/association.rb b/activerecord/lib/active_record/associations/builder/association.rb
index 37ba1c73b1..3911d1b520 100644
--- a/activerecord/lib/active_record/associations/builder/association.rb
+++ b/activerecord/lib/active_record/associations/builder/association.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/module/attribute_accessors'
+
 # This is the parent Association class which defines the variables
 # used by all associations.
 #
@@ -13,65 +15,67 @@ module ActiveRecord::Associations::Builder
   class Association #:nodoc:
     class << self
       attr_accessor :extensions
+      # TODO: This class accessor is needed to make activerecord-deprecated_finders work.
+      # We can move it to a constant in 5.0.
+      attr_accessor :valid_options
     end
     self.extensions = []
 
-    VALID_OPTIONS = [:class_name, :class, :foreign_key, :validate]
+    self.valid_options = [:class_name, :class, :foreign_key, :validate]
+
+    attr_reader :name, :scope, :options
 
     def self.build(model, name, scope, options, &block)
-      extension = define_extensions model, name, &block
-      reflection = create_reflection model, name, scope, options, extension
+      builder = create_builder model, name, scope, options, &block
+      reflection = builder.build(model)
       define_accessors model, reflection
       define_callbacks model, reflection
+      builder.define_extensions model
       reflection
     end
 
-    def self.create_reflection(model, name, scope, options, extension = nil)
+    def self.create_builder(model, name, scope, options, &block)
       raise ArgumentError, "association names must be a Symbol" unless name.kind_of?(Symbol)
 
+      new(model, name, scope, options, &block)
+    end
+
+    def initialize(model, name, scope, options)
+      # TODO: Move this to create_builder as soon we drop support to activerecord-deprecated_finders.
       if scope.is_a?(Hash)
         options = scope
         scope   = nil
       end
 
-      validate_options(options)
+      # TODO: Remove this model argument as soon we drop support to activerecord-deprecated_finders.
+      @name    = name
+      @scope   = scope
+      @options = options
 
-      scope = build_scope(scope, extension)
-
-      ActiveRecord::Reflection.create(macro, name, scope, options, model)
-    end
-
-    def self.build_scope(scope, extension)
-      new_scope = scope
+      validate_options
 
       if scope && scope.arity == 0
-        new_scope = proc { instance_exec(&scope) }
-      end
-
-      if extension
-        new_scope = wrap_scope new_scope, extension
+        @scope = proc { instance_exec(&scope) }
       end
-
-      new_scope
     end
 
-    def self.wrap_scope(scope, extension)
-      scope
+    def build(model)
+      ActiveRecord::Reflection.create(macro, name, scope, options, model)
     end
 
-    def self.macro
+    def macro
       raise NotImplementedError
     end
 
-    def self.valid_options(options)
-      VALID_OPTIONS + Association.extensions.flat_map(&:valid_options)
+    def valid_options
+      Association.valid_options + Association.extensions.flat_map(&:valid_options)
     end
 
-    def self.validate_options(options)
-      options.assert_valid_keys(valid_options(options))
+    def validate_options
+      options.assert_valid_keys(valid_options)
     end
 
-    def self.define_extensions(model, name)
+    def define_extensions(model)
     end
 
     def self.define_callbacks(model, reflection)
@@ -114,6 +118,8 @@ module ActiveRecord::Associations::Builder
       raise NotImplementedError
     end
 
+    private
+
     def self.add_before_destroy_callbacks(model, reflection)
       unless valid_dependent_options.include? reflection.options[:dependent]
         raise ArgumentError, "The :dependent option must be one of #{valid_dependent_options}, but is :#{reflection.options[:dependent]}"