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-rw-r--r--activerecord/lib/active_record/associations/alias_tracker.rb85
-rw-r--r--activerecord/lib/active_record/associations/has_many_through_association.rb6
-rw-r--r--activerecord/lib/active_record/associations/has_one_through_association.rb2
-rw-r--r--activerecord/lib/active_record/associations/join_dependency.rb32
-rw-r--r--activerecord/lib/active_record/associations/join_dependency/join_association.rb334
-rw-r--r--activerecord/lib/active_record/associations/preloader/through_association.rb5
-rw-r--r--activerecord/lib/active_record/associations/through_association.rb221
7 files changed, 433 insertions, 252 deletions
diff --git a/activerecord/lib/active_record/associations/alias_tracker.rb b/activerecord/lib/active_record/associations/alias_tracker.rb
new file mode 100644
index 0000000000..6fc2bfdb31
--- /dev/null
+++ b/activerecord/lib/active_record/associations/alias_tracker.rb
@@ -0,0 +1,85 @@
+require 'active_support/core_ext/string/conversions'
+
+module ActiveRecord
+ module Associations
+ # Keeps track of table aliases for ActiveRecord::Associations::ClassMethods::JoinDependency and
+ # ActiveRecord::Associations::ThroughAssociationScope
+ class AliasTracker # :nodoc:
+ attr_reader :aliases, :table_joins
+
+ # table_joins is an array of arel joins which might conflict with the aliases we assign here
+ def initialize(table_joins = [])
+ @aliases = Hash.new
+ @table_joins = table_joins
+ end
+
+ def aliased_table_for(table_name, aliased_name = nil)
+ table_alias = aliased_name_for(table_name, aliased_name)
+
+ if table_alias == table_name # TODO: Is this conditional necessary?
+ Arel::Table.new(table_name)
+ else
+ Arel::Table.new(table_name).alias(table_alias)
+ end
+ end
+
+ def aliased_name_for(table_name, aliased_name = nil)
+ aliased_name ||= table_name
+
+ initialize_count_for(table_name) if aliases[table_name].nil?
+
+ if aliases[table_name].zero?
+ # If it's zero, we can have our table_name
+ aliases[table_name] = 1
+ table_name
+ else
+ # Otherwise, we need to use an alias
+ aliased_name = connection.table_alias_for(aliased_name)
+
+ initialize_count_for(aliased_name) if aliases[aliased_name].nil?
+
+ # Update the count
+ aliases[aliased_name] += 1
+
+ if aliases[aliased_name] > 1
+ "#{truncate(aliased_name)}_#{aliases[aliased_name]}"
+ else
+ aliased_name
+ end
+ end
+ end
+
+ def pluralize(table_name)
+ ActiveRecord::Base.pluralize_table_names ? table_name.to_s.pluralize : table_name
+ end
+
+ private
+
+ def initialize_count_for(name)
+ aliases[name] = 0
+
+ unless Arel::Table === table_joins
+ # quoted_name should be downcased as some database adapters (Oracle) return quoted name in uppercase
+ quoted_name = connection.quote_table_name(name).downcase
+
+ aliases[name] += table_joins.map { |join|
+ # Table names + table aliases
+ join.left.downcase.scan(
+ /join(?:\s+\w+)?\s+(\S+\s+)?#{quoted_name}\son/
+ ).size
+ }.sum
+ end
+
+ aliases[name]
+ end
+
+ def truncate(name)
+ name[0..connection.table_alias_length-3]
+ end
+
+ def connection
+ ActiveRecord::Base.connection
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index acac68fda5..9d2b29685b 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -34,7 +34,9 @@ module ActiveRecord
end
def insert_record(record, validate = true)
+ ensure_not_nested
return if record.new_record? && !record.save(:validate => validate)
+
through_record(record).save!
update_counter(1)
record
@@ -59,6 +61,8 @@ module ActiveRecord
end
def build_record(attributes)
+ ensure_not_nested
+
record = super(attributes)
inverse = source_reflection.inverse_of
@@ -93,6 +97,8 @@ module ActiveRecord
end
def delete_records(records, method)
+ ensure_not_nested
+
through = owner.association(through_reflection.name)
scope = through.scoped.where(construct_join_attributes(*records))
diff --git a/activerecord/lib/active_record/associations/has_one_through_association.rb b/activerecord/lib/active_record/associations/has_one_through_association.rb
index d76d729303..fdf8ae1453 100644
--- a/activerecord/lib/active_record/associations/has_one_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_one_through_association.rb
@@ -12,6 +12,8 @@ module ActiveRecord
private
def create_through_record(record)
+ ensure_not_nested
+
through_proxy = owner.association(through_reflection.name)
through_record = through_proxy.send(:load_target)
diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index c7c3cf521c..504f25271c 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -5,18 +5,16 @@ module ActiveRecord
autoload :JoinBase, 'active_record/associations/join_dependency/join_base'
autoload :JoinAssociation, 'active_record/associations/join_dependency/join_association'
- attr_reader :join_parts, :reflections, :table_aliases, :active_record
+ attr_reader :join_parts, :reflections, :alias_tracker, :active_record
def initialize(base, associations, joins)
- @active_record = base
- @table_joins = joins
- @join_parts = [JoinBase.new(base)]
- @associations = {}
- @reflections = []
- @table_aliases = Hash.new do |h,name|
- h[name] = count_aliases_from_table_joins(name.downcase)
- end
- @table_aliases[base.table_name] = 1
+ @active_record = base
+ @table_joins = joins
+ @join_parts = [JoinBase.new(base)]
+ @associations = {}
+ @reflections = []
+ @alias_tracker = AliasTracker.new(joins)
+ @alias_tracker.aliased_name_for(base.table_name) # Updates the count for base.table_name to 1
build(associations)
end
@@ -45,20 +43,6 @@ module ActiveRecord
}.flatten
end
- def count_aliases_from_table_joins(name)
- return 0 if Arel::Table === @table_joins
-
- # quoted_name should be downcased as some database adapters (Oracle) return quoted name in uppercase
- quoted_name = active_record.connection.quote_table_name(name).downcase
-
- @table_joins.map { |join|
- # Table names + table aliases
- join.left.downcase.scan(
- /join(?:\s+\w+)?\s+(\S+\s+)?#{quoted_name}\son/
- ).size
- }.sum
- end
-
def instantiate(rows)
primary_key = join_base.aliased_primary_key
parents = {}
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_association.rb b/activerecord/lib/active_record/associations/join_dependency/join_association.rb
index ebe39c35fe..890e77fca9 100644
--- a/activerecord/lib/active_record/associations/join_dependency/join_association.rb
+++ b/activerecord/lib/active_record/associations/join_dependency/join_association.rb
@@ -18,10 +18,13 @@ module ActiveRecord
attr_accessor :join_type
# These implement abstract methods from the superclass
- attr_reader :aliased_prefix, :aliased_table_name
+ attr_reader :aliased_prefix
- delegate :options, :through_reflection, :source_reflection, :to => :reflection
+ attr_reader :tables
+
+ delegate :options, :through_reflection, :source_reflection, :through_reflection_chain, :to => :reflection
delegate :table, :table_name, :to => :parent, :prefix => :parent
+ delegate :alias_tracker, :to => :join_dependency
def initialize(reflection, join_dependency, parent = nil)
reflection.check_validity!
@@ -38,13 +41,7 @@ module ActiveRecord
@join_type = Arel::InnerJoin
@aliased_prefix = "t#{ join_dependency.join_parts.size }"
- # This must be done eagerly upon initialisation because the alias which is produced
- # depends on the state of the join dependency, but we want it to work the same way
- # every time.
- allocate_aliases
- @table = Arel::Table.new(
- table_name, :as => aliased_table_name, :engine => arel_engine
- )
+ setup_tables
end
def ==(other)
@@ -60,7 +57,95 @@ module ActiveRecord
end
def join_to(relation)
- send("join_#{reflection.macro}_to", relation)
+ # The chain starts with the target table, but we want to end with it here (makes
+ # more sense in this context)
+ chain = through_reflection_chain.reverse
+
+ foreign_table = parent_table
+ index = 0
+
+ chain.each do |reflection|
+ table = tables[index]
+ conditions = []
+
+ if reflection.source_reflection.nil?
+ case reflection.macro
+ when :belongs_to
+ key = reflection.association_primary_key
+ foreign_key = reflection.foreign_key
+ when :has_many, :has_one
+ key = reflection.foreign_key
+ foreign_key = reflection.active_record_primary_key
+
+ conditions << polymorphic_conditions(reflection, table)
+ when :has_and_belongs_to_many
+ # For habtm, we need to deal with the join table at the same time as the
+ # target table (because unlike a :through association, there is no reflection
+ # to represent the join table)
+ table, join_table = table
+
+ join_key = reflection.foreign_key
+ join_foreign_key = reflection.active_record.primary_key
+
+ relation = relation.join(join_table, join_type).on(
+ join_table[join_key].
+ eq(foreign_table[join_foreign_key])
+ )
+
+ # We've done the first join now, so update the foreign_table for the second
+ foreign_table = join_table
+
+ key = reflection.klass.primary_key
+ foreign_key = reflection.association_foreign_key
+ end
+ else
+ case reflection.source_reflection.macro
+ when :belongs_to
+ key = reflection.association_primary_key
+ foreign_key = reflection.foreign_key
+
+ conditions << source_type_conditions(reflection, foreign_table)
+ when :has_many, :has_one
+ key = reflection.foreign_key
+ foreign_key = reflection.source_reflection.active_record_primary_key
+ when :has_and_belongs_to_many
+ table, join_table = table
+
+ join_key = reflection.foreign_key
+ join_foreign_key = reflection.klass.primary_key
+
+ relation = relation.join(join_table, join_type).on(
+ join_table[join_key].
+ eq(foreign_table[join_foreign_key])
+ )
+
+ foreign_table = join_table
+
+ key = reflection.klass.primary_key
+ foreign_key = reflection.association_foreign_key
+ end
+ end
+
+ conditions << table[key].eq(foreign_table[foreign_key])
+
+ conditions << reflection_conditions(index, table)
+ conditions << sti_conditions(reflection, table)
+
+ ands = relation.create_and(conditions.flatten.compact)
+
+ join = relation.create_join(
+ table,
+ relation.create_on(ands),
+ join_type)
+
+ relation = relation.from(join)
+
+ # The current table in this iteration becomes the foreign table in the next
+ foreign_table = table
+ index += 1
+ end
+
+ relation
end
def join_relation(joining_relation)
@@ -68,42 +153,59 @@ module ActiveRecord
joining_relation.joins(self)
end
- attr_reader :table
- # More semantic name given we are talking about associations
- alias_method :target_table, :table
-
- protected
-
- def aliased_table_name_for(name, suffix = nil)
- aliases = @join_dependency.table_aliases
-
- if aliases[name] != 0 # We need an alias
- connection = active_record.connection
-
- name = connection.table_alias_for "#{pluralize(reflection.name)}_#{parent_table_name}#{suffix}"
- aliases[name] += 1
- name = name[0, connection.table_alias_length-3] + "_#{aliases[name]}" if aliases[name] > 1
+ def table
+ if tables.last.is_a?(Array)
+ tables.last.first
else
- aliases[name] += 1
+ tables.last
end
+ end
- name
+ def aliased_table_name
+ table.table_alias || table.name
end
- def pluralize(table_name)
- ActiveRecord::Base.pluralize_table_names ? table_name.to_s.pluralize : table_name
+ protected
+
+ def table_alias_for(reflection, join = false)
+ name = alias_tracker.pluralize(reflection.name)
+ name << "_#{parent_table_name}"
+ name << "_join" if join
+ name
end
private
- def allocate_aliases
- @aliased_table_name = aliased_table_name_for(table_name)
+ # Generate aliases and Arel::Table instances for each of the tables which we will
+ # later generate joins for. We must do this in advance in order to correctly allocate
+ # the proper alias.
+ def setup_tables
+ @tables = through_reflection_chain.map do |reflection|
+ table = alias_tracker.aliased_table_for(
+ reflection.table_name,
+ table_alias_for(reflection, reflection != self.reflection)
+ )
+
+ # For habtm, we have two Arel::Table instances related to a single reflection, so
+ # we just store them as a pair in the array.
+ if reflection.macro == :has_and_belongs_to_many ||
+ (reflection.source_reflection && reflection.source_reflection.macro == :has_and_belongs_to_many)
+
+ join_table = alias_tracker.aliased_table_for(
+ (reflection.source_reflection || reflection).options[:join_table],
+ table_alias_for(reflection, true)
+ )
- if reflection.macro == :has_and_belongs_to_many
- @aliased_join_table_name = aliased_table_name_for(reflection.options[:join_table], "_join")
- elsif [:has_many, :has_one].include?(reflection.macro) && reflection.options[:through]
- @aliased_join_table_name = aliased_table_name_for(reflection.through_reflection.klass.table_name, "_join")
+ [table, join_table]
+ else
+ table
+ end
end
+
+ # The joins are generated from the through_reflection_chain in reverse order, so
+ # reverse the tables too (but it's important to generate the aliases in the 'forward'
+ # order, which is why we only do the reversal now.
+ @tables.reverse!
end
def process_conditions(conditions, table_name)
@@ -118,161 +220,39 @@ module ActiveRecord
active_record.send(:sanitize_sql, condition, table_name)
end
- def join_target_table(relation, condition)
- conditions = [condition]
+ def reflection_conditions(index, table)
+ reflection.through_conditions.reverse[index].map do |condition|
+ process_conditions(condition, table.table_alias || table.name)
+ end
+ end
- # If the target table is an STI model then we must be sure to only include records of
- # its type and its sub-types.
- unless active_record.descends_from_active_record?
- sti_column = target_table[active_record.inheritance_column]
- subclasses = active_record.descendants
- sti_condition = sti_column.eq(active_record.sti_name)
+ def sti_conditions(reflection, table)
+ unless reflection.klass.descends_from_active_record?
+ sti_column = table[reflection.klass.inheritance_column]
+ sti_condition = sti_column.eq(reflection.klass.sti_name)
+ subclasses = reflection.klass.descendants
- conditions << subclasses.inject(sti_condition) { |attr,subclass|
+ # TODO: use IN (...), or possibly AR::Base#type_condition
+ subclasses.inject(sti_condition) { |attr,subclass|
attr.or(sti_column.eq(subclass.sti_name))
}
end
-
- # If the reflection has conditions, add them
- if options[:conditions]
- conditions << process_conditions(options[:conditions], aliased_table_name)
- end
-
- ands = relation.create_and(conditions)
-
- join = relation.create_join(
- target_table,
- relation.create_on(ands),
- join_type)
-
- relation.from join
- end
-
- def join_has_and_belongs_to_many_to(relation)
- join_table = Arel::Table.new(
- options[:join_table]
- ).alias(@aliased_join_table_name)
-
- fk = options[:foreign_key] || reflection.active_record.to_s.foreign_key
- klass_fk = options[:association_foreign_key] || reflection.klass.to_s.foreign_key
-
- relation = relation.join(join_table, join_type)
- relation = relation.on(
- join_table[fk].
- eq(parent_table[reflection.active_record.primary_key])
- )
-
- join_target_table(
- relation,
- target_table[reflection.klass.primary_key].
- eq(join_table[klass_fk])
- )
end
- def join_has_many_to(relation)
- if reflection.options[:through]
- join_has_many_through_to(relation)
- elsif reflection.options[:as]
- join_has_many_polymorphic_to(relation)
- else
- foreign_key = options[:foreign_key] || reflection.active_record.name.foreign_key
- primary_key = options[:primary_key] || parent.primary_key
-
- join_target_table(
- relation,
- target_table[foreign_key].
- eq(parent_table[primary_key])
- )
+ def source_type_conditions(reflection, foreign_table)
+ if reflection.options[:source_type]
+ foreign_table[reflection.source_reflection.foreign_type].
+ eq(reflection.options[:source_type])
end
end
- alias :join_has_one_to :join_has_many_to
-
- def join_has_many_through_to(relation)
- join_table = Arel::Table.new(
- through_reflection.klass.table_name
- ).alias @aliased_join_table_name
-
- jt_conditions = []
- first_key = second_key = nil
-
- if through_reflection.macro == :belongs_to
- jt_primary_key = through_reflection.foreign_key
- jt_foreign_key = through_reflection.association_primary_key
- else
- jt_primary_key = through_reflection.active_record_primary_key
- jt_foreign_key = through_reflection.foreign_key
-
- if through_reflection.options[:as] # has_many :through against a polymorphic join
- jt_conditions <<
- join_table["#{through_reflection.options[:as]}_type"].
- eq(parent.active_record.base_class.name)
- end
- end
-
- case source_reflection.macro
- when :has_many
- second_key = options[:foreign_key] || primary_key
-
- if source_reflection.options[:as]
- first_key = "#{source_reflection.options[:as]}_id"
- else
- first_key = through_reflection.klass.base_class.to_s.foreign_key
- end
-
- unless through_reflection.klass.descends_from_active_record?
- jt_conditions <<
- join_table[through_reflection.active_record.inheritance_column].
- eq(through_reflection.klass.sti_name)
- end
- when :belongs_to
- first_key = primary_key
-
- if reflection.options[:source_type]
- second_key = source_reflection.association_foreign_key
-
- jt_conditions <<
- join_table[reflection.source_reflection.foreign_type].
- eq(reflection.options[:source_type])
- else
- second_key = source_reflection.foreign_key
- end
- end
-
- jt_conditions <<
- parent_table[jt_primary_key].
- eq(join_table[jt_foreign_key])
- if through_reflection.options[:conditions]
- jt_conditions << process_conditions(through_reflection.options[:conditions], aliased_table_name)
+ def polymorphic_conditions(reflection, table)
+ if reflection.options[:as]
+ table[reflection.type].
+ eq(reflection.active_record.base_class.name)
end
-
- relation = relation.join(join_table, join_type).on(*jt_conditions)
-
- join_target_table(
- relation,
- target_table[first_key].eq(join_table[second_key])
- )
end
- def join_has_many_polymorphic_to(relation)
- join_target_table(
- relation,
- target_table["#{reflection.options[:as]}_id"].
- eq(parent_table[parent.primary_key]).and(
- target_table["#{reflection.options[:as]}_type"].
- eq(parent.active_record.base_class.name))
- )
- end
-
- def join_belongs_to_to(relation)
- foreign_key = options[:foreign_key] || reflection.foreign_key
- primary_key = options[:primary_key] || reflection.klass.primary_key
-
- join_target_table(
- relation,
- target_table[primary_key].eq(parent_table[foreign_key])
- )
- end
end
end
end
diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index d630fc4c63..ad6374d09a 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -19,8 +19,9 @@ module ActiveRecord
source_reflection.name, options
).run
- through_records.each do |owner, owner_through_records|
- owner_through_records.map! { |r| r.send(source_reflection.name) }.flatten!
+ through_records.each do |owner, records|
+ records.map! { |r| r.send(source_reflection.name) }.flatten!
+ records.compact!
end
end
diff --git a/activerecord/lib/active_record/associations/through_association.rb b/activerecord/lib/active_record/associations/through_association.rb
index e1d60ccb17..ed24373cba 100644
--- a/activerecord/lib/active_record/associations/through_association.rb
+++ b/activerecord/lib/active_record/associations/through_association.rb
@@ -1,9 +1,12 @@
+require 'enumerator'
+
module ActiveRecord
# = Active Record Through Association
module Associations
module ThroughAssociation #:nodoc:
- delegate :source_options, :through_options, :source_reflection, :through_reflection, :to => :reflection
+ delegate :source_options, :through_options, :source_reflection, :through_reflection,
+ :through_reflection_chain, :through_conditions, :to => :reflection
protected
@@ -13,10 +16,12 @@ module ActiveRecord
def association_scope
scope = super.joins(construct_joins)
- scope = add_conditions(scope)
+ scope = scope.where(reflection_conditions(0))
+
unless options[:include]
scope = scope.includes(source_options[:include])
end
+
scope
end
@@ -30,6 +35,7 @@ module ActiveRecord
{ }
end
+ # TODO: Needed?
def aliased_through_table
name = through_reflection.table_name
@@ -39,41 +45,101 @@ module ActiveRecord
end
def construct_owner_conditions
- super(aliased_through_table, through_reflection)
+ reflection = through_reflection_chain.last
+
+ if reflection.macro == :has_and_belongs_to_many
+ table = tables[reflection].first
+ else
+ table = Array.wrap(tables[reflection]).first
+ end
+
+ super(table, reflection)
end
def construct_joins
- right = aliased_through_table
- left = reflection.klass.arel_table
+ joins, right_index = [], 1
- conditions = []
+ # Iterate over each pair in the through reflection chain, joining them together
+ through_reflection_chain.each_cons(2) do |left, right|
+ left_table, right_table = tables[left], tables[right]
- if source_reflection.macro == :belongs_to
- reflection_primary_key = source_reflection.association_primary_key
- source_primary_key = source_reflection.foreign_key
+ if left.source_reflection.nil?
+ case left.macro
+ when :belongs_to
+ joins << inner_join(
+ right_table,
+ left_table[left.association_primary_key],
+ right_table[left.foreign_key],
+ reflection_conditions(right_index)
+ )
+ when :has_many, :has_one
+ joins << inner_join(
+ right_table,
+ left_table[left.foreign_key],
+ right_table[right.association_primary_key],
+ polymorphic_conditions(left, left),
+ reflection_conditions(right_index)
+ )
+ when :has_and_belongs_to_many
+ joins << inner_join(
+ right_table,
+ left_table.first[left.foreign_key],
+ right_table[right.klass.primary_key],
+ reflection_conditions(right_index)
+ )
+ end
+ else
+ case left.source_reflection.macro
+ when :belongs_to
+ joins << inner_join(
+ right_table,
+ left_table[left.association_primary_key],
+ right_table[left.foreign_key],
+ source_type_conditions(left),
+ reflection_conditions(right_index)
+ )
+ when :has_many, :has_one
+ if right.macro == :has_and_belongs_to_many
+ join_table, right_table = tables[right]
+ end
- if options[:source_type]
- column = source_reflection.foreign_type
- conditions <<
- right[column].eq(options[:source_type])
- end
- else
- reflection_primary_key = source_reflection.foreign_key
- source_primary_key = source_reflection.active_record_primary_key
+ joins << inner_join(
+ right_table,
+ left_table[left.foreign_key],
+ right_table[left.source_reflection.active_record_primary_key],
+ polymorphic_conditions(left, left.source_reflection),
+ reflection_conditions(right_index)
+ )
- if source_options[:as]
- column = "#{source_options[:as]}_type"
- conditions <<
- left[column].eq(through_reflection.klass.name)
+ if right.macro == :has_and_belongs_to_many
+ joins << inner_join(
+ join_table,
+ right_table[right.klass.primary_key],
+ join_table[right.association_foreign_key]
+ )
+ end
+ when :has_and_belongs_to_many
+ join_table, left_table = tables[left]
+
+ joins << inner_join(
+ join_table,
+ left_table[left.klass.primary_key],
+ join_table[left.association_foreign_key]
+ )
+
+ joins << inner_join(
+ right_table,
+ join_table[left.foreign_key],
+ right_table[right.klass.primary_key],
+ reflection_conditions(right_index)
+ )
+ end
end
- end
- conditions <<
- left[reflection_primary_key].eq(right[source_primary_key])
+ right_index += 1
+ end
- right.create_join(
- right,
- right.create_on(right.create_and(conditions)))
+ joins
end
# Construct attributes for :through pointing to owner and associate. This is used by the
@@ -112,37 +178,88 @@ module ActiveRecord
end
end
- # The reason that we are operating directly on the scope here (rather than passing
- # back some arel conditions to be added to the scope) is because scope.where([x, y])
- # has a different meaning to scope.where(x).where(y) - the first version might
- # perform some substitution if x is a string.
- def add_conditions(scope)
- unless through_reflection.klass.descends_from_active_record?
- scope = scope.where(through_reflection.klass.send(:type_condition))
+ def alias_tracker
+ @alias_tracker ||= AliasTracker.new
+ end
+
+ # TODO: It is decidedly icky to have an array for habtm entries, and no array for others
+ def tables
+ @tables ||= begin
+ Hash[
+ through_reflection_chain.map do |reflection|
+ table = alias_tracker.aliased_table_for(
+ reflection.table_name,
+ table_alias_for(reflection, reflection != self.reflection)
+ )
+
+ if reflection.macro == :has_and_belongs_to_many ||
+ (reflection.source_reflection &&
+ reflection.source_reflection.macro == :has_and_belongs_to_many)
+
+ join_table = alias_tracker.aliased_table_for(
+ (reflection.source_reflection || reflection).options[:join_table],
+ table_alias_for(reflection, true)
+ )
+
+ [reflection, [join_table, table]]
+ else
+ [reflection, table]
+ end
+ end
+ ]
end
+ end
- scope = scope.where(interpolate(source_options[:conditions]))
- scope.where(through_conditions)
+ def table_alias_for(reflection, join = false)
+ name = alias_tracker.pluralize(reflection.name)
+ name << "_#{self.reflection.name}"
+ name << "_join" if join
+ name
end
- # If there is a hash of conditions then we make sure the keys are scoped to the
- # through table name if left ambiguous.
- def through_conditions
- conditions = interpolate(through_options[:conditions])
+ def inner_join(table, left_column, right_column, *conditions)
+ conditions << left_column.eq(right_column)
- if conditions.is_a?(Hash)
- Hash[conditions.map { |key, value|
- unless value.is_a?(Hash) || key.to_s.include?('.')
- key = aliased_through_table.name + '.' + key.to_s
- end
+ table.create_join(
+ table,
+ table.create_on(table.create_and(conditions.flatten.compact)))
+ end
- [key, value]
- }]
- else
- conditions
+ def reflection_conditions(index)
+ reflection = through_reflection_chain[index]
+ conditions = through_conditions[index].dup
+
+ # TODO: maybe this should go in Reflection#through_conditions directly?
+ unless reflection.klass.descends_from_active_record?
+ conditions << reflection.klass.send(:type_condition)
+ end
+
+ unless conditions.empty?
+ conditions.map! do |condition|
+ condition = reflection.klass.send(:sanitize_sql, interpolate(condition), reflection.table_name)
+ condition = Arel.sql(condition) unless condition.is_a?(Arel::Node)
+ condition
+ end
+
+ Arel::Nodes::And.new(conditions)
end
end
+ def polymorphic_conditions(reflection, polymorphic_reflection)
+ if polymorphic_reflection.options[:as]
+ tables[reflection][polymorphic_reflection.type].
+ eq(polymorphic_reflection.active_record.base_class.name)
+ end
+ end
+
+ def source_type_conditions(reflection)
+ if reflection.options[:source_type]
+ tables[reflection.through_reflection][reflection.foreign_type].
+ eq(reflection.options[:source_type])
+ end
+ end
+
+ # TODO: Think about this in the context of nested associations
def stale_state
if through_reflection.macro == :belongs_to
owner[through_reflection.foreign_key].to_s
@@ -153,6 +270,12 @@ module ActiveRecord
through_reflection.macro == :belongs_to &&
!owner[through_reflection.foreign_key].nil?
end
+
+ def ensure_not_nested
+ if reflection.nested?
+ raise HasManyThroughNestedAssociationsAreReadonly.new(owner, reflection)
+ end
+ end
end
end
end