Class: Formed::Reflection::ThroughReflection

Inherits:
AbstractReflection show all
Defined in:
lib/formed/reflection.rb

Overview

Holds all the metadata about a :through association as it was specified in the Active Record class.

Instance Method Summary collapse

Methods inherited from AbstractReflection

#alias_candidate, #build_association, #build_scope, #chain, #check_validity_of_inverse!, #class_name, #constraints, #inverse_of, #scopes, #strict_loading?, #strict_loading_violation_message, #table_name

Constructor Details

#initialize(delegate_reflection) ⇒ ThroughReflection

Returns a new instance of ThroughReflection.



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# File 'lib/formed/reflection.rb', line 657

def initialize(delegate_reflection)
  @delegate_reflection = delegate_reflection
  @klass = delegate_reflection.options[:anonymous_class]
  @source_reflection_name = delegate_reflection.options[:source]

  ensure_option_not_given_as_class!(:source_type)
end

Instance Method Details

#check_validity! ⇒ Object

Raises:

  • (HasManyThroughAssociationNotFoundError) 


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# File 'lib/formed/reflection.rb', line 688

def check_validity!
  raise HasManyThroughAssociationNotFoundError.new(active_record, self) if through_reflection.nil?

  if through_reflection.polymorphic?
    raise HasOneAssociationPolymorphicThroughError.new(active_record.name, self) if has_one?

    raise HasManyThroughAssociationPolymorphicThroughError.new(active_record.name, self)

  end

  raise HasManyThroughSourceAssociationNotFoundError, self if source_reflection.nil?

  if options[:source_type] && !source_reflection.polymorphic?
    raise HasManyThroughAssociationPointlessSourceTypeError.new(active_record.name, self, source_reflection)
  end

  if source_reflection.polymorphic? && options[:source_type].nil?
    raise HasManyThroughAssociationPolymorphicSourceError.new(active_record.name, self, source_reflection)
  end

  if has_one? && through_reflection.collection?
    raise HasOneThroughCantAssociateThroughCollection.new(active_record.name, self, through_reflection)
  end

  if parent_reflection.nil?
    reflections = active_record.reflections.keys.map(&:to_sym)

    if reflections.index(through_reflection.name) > reflections.index(name)
      raise HasManyThroughOrderError.new(active_record.name, self, through_reflection)
    end
  end

  check_validity_of_inverse!
end

#klass ⇒ Object 



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# File 'lib/formed/reflection.rb', line 669

def klass
  @klass ||= delegate_reflection.compute_class(class_name)
end

#source_reflection_names ⇒ Object

Gets an array of possible :through source reflection names in both singular and plural form.

class Post < ActiveRecord::Base
  has_many :taggings
  has_many :tags, through: :taggings
end

tags_reflection = Post.reflect_on_association(:tags)
tags_reflection.source_reflection_names
# => [:tag, :tags]



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# File 'lib/formed/reflection.rb', line 684

def source_reflection_names
  options[:source] ? [options[:source]] : [name.to_s.singularize, name].uniq
end

#through_reflection? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/formed/reflection.rb', line 665

def through_reflection?
  true
end