module ActiveRecord
class Relation
JoinOperation = Struct.new(:relation, :join_class, :on)
ASSOCIATION_METHODS = [:includes, :eager_load, :preload]
MULTI_VALUE_METHODS = [:select, :group, :order, :joins, :where, :having]
SINGLE_VALUE_METHODS = [:limit, :offset, :lock, :readonly, :create_with, :from]
include FinderMethods, CalculationMethods, SpawnMethods, QueryMethods
delegate :length, :collect, :map, :each, :all?, :include?, :to => :to_a
attr_reader :table, :klass
def initialize(klass, table)
@klass, @table = klass, table
(ASSOCIATION_METHODS + MULTI_VALUE_METHODS).each {|v| instance_variable_set(:"@#{v}_values", [])}
end
def new(*args, &block)
with_create_scope { @klass.new(*args, &block) }
end
alias build new
def create(*args, &block)
with_create_scope { @klass.create(*args, &block) }
end
def create!(*args, &block)
with_create_scope { @klass.create!(*args, &block) }
end
def respond_to?(method, include_private = false)
return true if arel.respond_to?(method, include_private) || Array.method_defined?(method)
if match = DynamicFinderMatch.match(method)
return true if @klass.send(:all_attributes_exists?, match.attribute_names)
elsif match = DynamicScopeMatch.match(method)
return true if @klass.send(:all_attributes_exists?, match.attribute_names)
else
super
end
end
def to_a
return @records if loaded?
find_with_associations = @eager_load_values.any? || (@includes_values.any? && references_eager_loaded_tables?)
@records = if find_with_associations
begin
options = {
:select => @select_values.any? ? @select_values.join(", ") : nil,
:joins => arel.joins(arel),
:group => @group_values.any? ? @group_values.join(", ") : nil,
:order => order_clause,
:conditions => where_clause,
:limit => arel.taken,
:offset => arel.skipped,
:from => (arel.send(:from_clauses) if arel.send(:sources).present?)
}
including = (@eager_load_values + @includes_values).uniq
join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, including, nil)
@klass.send(:find_with_associations, options, join_dependency)
rescue ThrowResult
[]
end
else
@klass.find_by_sql(arel.to_sql)
end
preload = @preload_values
preload += @includes_values unless find_with_associations
preload.each {|associations| @klass.send(:preload_associations, @records, associations) }
# @readonly_value is true only if set explicity. @implicit_readonly is true if there are JOINS and no explicit SELECT.
readonly = @readonly_value.nil? ? @implicit_readonly : @readonly_value
@records.each { |record| record.readonly! } if readonly
@loaded = true
@records
end
alias all to_a
def size
loaded? ? @records.length : count
end
def empty?
loaded? ? @records.empty? : count.zero?
end
def any?
if block_given?
to_a.any? { |*block_args| yield(*block_args) }
else
!empty?
end
end
def many?
if block_given?
to_a.many? { |*block_args| yield(*block_args) }
else
arel.send(:taken).present? ? to_a.many? : size > 1
end
end
def destroy_all
to_a.each {|object| object.destroy}
reset
end
def delete_all
arel.delete.tap { reset }
end
def delete(id_or_array)
where(@klass.primary_key => id_or_array).delete_all
end
def loaded?
@loaded
end
def reload
reset
to_a # force reload
self
end
def reset
@first = @last = @to_sql = @order_clause = @scope_for_create = @arel = @loaded = nil
@records = []
self
end
def primary_key
@primary_key ||= table[@klass.primary_key]
end
def to_sql
@to_sql ||= arel.to_sql
end
def scope_for_create
@scope_for_create ||= begin
@create_with_value || wheres.inject({}) do |hash, where|
hash[where.operand1.name] = where.operand2.value if where.is_a?(Arel::Predicates::Equality)
hash
end
end
end
protected
def method_missing(method, *args, &block)
if arel.respond_to?(method)
arel.send(method, *args, &block)
elsif Array.method_defined?(method)
to_a.send(method, *args, &block)
elsif match = DynamicFinderMatch.match(method)
attributes = match.attribute_names
super unless @klass.send(:all_attributes_exists?, attributes)
if match.finder?
find_by_attributes(match, attributes, *args)
elsif match.instantiator?
find_or_instantiator_by_attributes(match, attributes, *args, &block)
end
else
super
end
end
private
def with_create_scope
@klass.send(:with_scope, :create => scope_for_create, :find => {}) { yield }
end
def where_clause(join_string = " AND ")
arel.send(:where_clauses).join(join_string)
end
def order_clause
@order_clause ||= arel.send(:order_clauses).join(', ')
end
def references_eager_loaded_tables?
joined_tables = (tables_in_string(arel.joins(arel)) + [table.name, table.table_alias]).compact.uniq
(tables_in_string(to_sql) - joined_tables).any?
end
def tables_in_string(string)
return [] if string.blank?
string.scan(/([a-zA-Z_][\.\w]+).?\./).flatten.uniq
end
end
end