method

scope_chain

v4.2.9 - Show latest stable - 0 notes - Class: ActiveRecord::Reflection::ThroughReflection

1.0.0
1.1.6
1.2.6
2.0.3
2.1.0
2.2.1
2.3.8
3.0.0
3.0.9
3.1.0
3.2.1
3.2.8
3.2.13
4.0.2 (0)
4.1.8 (0)
4.2.1 (0)
4.2.7 (0)
4.2.9 (0)
5.0.0.1 (0)
5.1.7
5.2.3
6.0.0
6.1.3.1
6.1.7.7
7.0.0
7.1.3.2
7.1.3.4
What's this?

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.

Show source

# 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

Related methods