The AliasTracker#aliased_table_for needs the type caster for the joined association, not the join root

3 files changed, 18 insertions, 14 deletions

diff --git a/activerecord/lib/active_record/associations/alias_tracker.rb b/activerecord/lib/active_record/associations/alias_tracker.rb
index 4a5c821607..104de4f69d 100644
--- a/activerecord/lib/active_record/associations/alias_tracker.rb
+++ b/activerecord/lib/active_record/associations/alias_tracker.rb
@@ -4,21 +4,21 @@ module ActiveRecord
   module Associations
     # Keeps track of table aliases for ActiveRecord::Associations::JoinDependency
     class AliasTracker # :nodoc:
-      def self.create(connection, initial_table, type_caster)
+      def self.create(connection, initial_table)
         aliases = Hash.new(0)
         aliases[initial_table] = 1
-        new connection, aliases, type_caster
+        new(connection, aliases)
       end
 
-      def self.create_with_joins(connection, initial_table, joins, type_caster)
+      def self.create_with_joins(connection, initial_table, joins)
         if joins.empty?
-          create(connection, initial_table, type_caster)
+          create(connection, initial_table)
         else
           aliases = Hash.new { |h, k|
             h[k] = initial_count_for(connection, k, joins)
           }
           aliases[initial_table] = 1
-          new connection, aliases, type_caster
+          new(connection, aliases)
         end
       end
 
@@ -51,17 +51,16 @@ module ActiveRecord
       end
 
       # table_joins is an array of arel joins which might conflict with the aliases we assign here
-      def initialize(connection, aliases, type_caster)
+      def initialize(connection, aliases)
         @aliases    = aliases
         @connection = connection
-        @type_caster = type_caster
       end
 
-      def aliased_table_for(table_name, aliased_name)
+      def aliased_table_for(table_name, aliased_name, type_caster)
         if aliases[table_name].zero?
           # If it's zero, we can have our table_name
           aliases[table_name] = 1
-          Arel::Table.new(table_name, type_caster: @type_caster)
+          Arel::Table.new(table_name, type_caster: type_caster)
         else
           # Otherwise, we need to use an alias
           aliased_name = @connection.table_alias_for(aliased_name)
@@ -74,7 +73,7 @@ module ActiveRecord
           else
             aliased_name
           end
-          Arel::Table.new(table_name, type_caster: @type_caster).alias(table_alias)
+          Arel::Table.new(table_name, type_caster: type_caster).alias(table_alias)
         end
       end
 
diff --git a/activerecord/lib/active_record/associations/association_scope.rb b/activerecord/lib/active_record/associations/association_scope.rb
index 1593b94f0c..4ce4252224 100644
--- a/activerecord/lib/active_record/associations/association_scope.rb
+++ b/activerecord/lib/active_record/associations/association_scope.rb
@@ -21,7 +21,7 @@ module ActiveRecord
         reflection = association.reflection
         scope = klass.unscoped
         owner = association.owner
-        alias_tracker = AliasTracker.create connection, association.klass.table_name, klass.type_caster
+        alias_tracker = AliasTracker.create connection, association.klass.table_name
         chain_head, chain_tail = get_chain(reflection, association, alias_tracker)
 
         scope.extending! reflection.extensions
@@ -112,7 +112,11 @@ module ActiveRecord
           runtime_reflection = Reflection::RuntimeReflection.new(reflection, association)
           previous_reflection = runtime_reflection
           reflection.chain.drop(1).each do |refl|
-            alias_name = tracker.aliased_table_for(refl.table_name, refl.alias_candidate(name))
+            alias_name = tracker.aliased_table_for(
+              refl.table_name,
+              refl.alias_candidate(name),
+              refl.klass.type_caster
+            )
             proxy = ReflectionProxy.new(refl, alias_name)
             previous_reflection.next = proxy
             previous_reflection = proxy
diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index 83e5c23cc4..bc66194aef 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -93,7 +93,7 @@ module ActiveRecord
       #    joins # =>  []
       #
       def initialize(base, associations, joins, eager_loading: true)
-        @alias_tracker = AliasTracker.create_with_joins(base.connection, base.table_name, joins, base.type_caster)
+        @alias_tracker = AliasTracker.create_with_joins(base.connection, base.table_name, joins)
         @eager_loading = eager_loading
         tree = self.class.make_tree associations
         @join_root = JoinBase.new base, build(tree, base)
@@ -185,7 +185,8 @@ module ActiveRecord
           node.reflection.chain.map { |reflection|
             alias_tracker.aliased_table_for(
               reflection.table_name,
-              table_alias_for(reflection, parent, reflection != node.reflection)
+              table_alias_for(reflection, parent, reflection != node.reflection),
+              reflection.klass.type_caster
             )
           }
         end