method

scope_chain

v4.2.9 - Show latest stable - Class: ActiveRecord::Reflection::ThroughReflection

scope_chain()

public

Consider the following example:

class Person
  has_many :articles
  has_many :comment_tags, through: :articles
end

class Article
  has_many :comments
  has_many :comment_tags, through: :comments, source: :tags
end

class Comment
  has_many :tags
end

There may be scopes on Person.comment_tags, Article.comment_tags and/or Comment.tags, but only Comment.tags will be represented in the #chain. So this method creates an array of scopes corresponding to the chain.

# File activerecord/lib/active_record/reflection.rb, line 736
      def scope_chain
        @scope_chain ||= begin
          scope_chain = source_reflection.scope_chain.map(&:dup)

          # Add to it the scope from this reflection (if any)
          scope_chain.first << scope if scope

          through_scope_chain = through_reflection.scope_chain.map(&:dup)

          if options[:source_type]
            type = foreign_type
            source_type = options[:source_type]
            through_scope_chain.first << lambda { |object|
              where(type => source_type)
            }
          end

          # Recursively fill out the rest of the array from the through reflection
          scope_chain + through_scope_chain
        end
      end

scope_chain

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