Allow symbols using "dot notation" to be passed to where

In 04ac5655be I assumed that we would
never want to pass the "table_name.column_name" form to where with a
symbol. However, in Ruby 2.2 and later, you can quote symbols using the
new hash syntax, so it's a semi-reasonable thing to do if we want to
support the dot notation (which I'd rather deprecate, but that would be
too painful of a migration).

Instead we've changed the definition of "this is a table name with a
dot" to when the value associated is a hash. It would make very little
sense to write `where("table_name.column_name": { foo: :bar })` in any
scenario (other than equality for a JSON column which we don't support
through `where` in this way).

Close #24514.

activerecord/lib/active_record/associations/association_scope.rb

@@ -64,11 +64,11 @@ module ActiveRecord
         foreign_key = join_keys.foreign_key
 
         value = transform_value(owner[foreign_key])
-        scope = scope.where(table.name.to_sym => { key => value })
+        scope = scope.where(table.name => { key => value })
 
         if reflection.type
           polymorphic_type = transform_value(owner.class.base_class.name)
-          scope = scope.where(table.name.to_sym => { reflection.type => polymorphic_type })
+          scope = scope.where(table.name => { reflection.type => polymorphic_type })
         end
 
         scope

activerecord/lib/active_record/relation/predicate_builder.rb

@@ -84,7 +84,6 @@ module ActiveRecord
       return ["1=0"] if attributes.empty?
 
       attributes.flat_map do |key, value|
-        key = key.to_s
         if value.is_a?(Hash)
           associated_predicate_builder(key).expand_from_hash(value)
         else
@@ -137,11 +136,11 @@ module ActiveRecord
     end
 
     def convert_dot_notation_to_hash(attributes)
-      dot_notation = attributes.keys.select do |s|
-        s.respond_to?(:include?) && s.include?(".".freeze)
+      dot_notation = attributes.select do |k, v|
+        k.include?(".".freeze) && !v.is_a?(Hash)
       end
 
-      dot_notation.each do |key|
+      dot_notation.each_key do |key|
         table_name, column_name = key.split(".".freeze)
         value = attributes.delete(key)
         attributes[table_name] ||= {}

activerecord/lib/active_record/relation/where_clause_factory.rb

@@ -15,6 +15,7 @@ module ActiveRecord
         when Hash
           attributes = predicate_builder.resolve_column_aliases(opts)
           attributes = klass.send(:expand_hash_conditions_for_aggregates, attributes)
+          attributes.stringify_keys!
 
           attributes, binds = predicate_builder.create_binds(attributes)
 

activerecord/test/cases/finder_test.rb

@@ -652,11 +652,16 @@ class FinderTest < ActiveRecord::TestCase
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where(approved: true).find(1) }
   end
 
-  def test_find_on_hash_conditions_with_explicit_table_name
+  def test_find_on_hash_conditions_with_qualified_attribute_dot_notation_string
     assert Topic.where('topics.approved' => false).find(1)
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where('topics.approved' => true).find(1) }
   end
 
+  def test_find_on_hash_conditions_with_qualified_attribute_dot_notation_symbol
+    assert Topic.where('topics.approved': false).find(1)
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.where('topics.approved': true).find(1) }
+  end
+
   def test_find_on_hash_conditions_with_hashed_table_name
     assert Topic.where(topics: { approved: false }).find(1)
     assert_raise(ActiveRecord::RecordNotFound) { Topic.where(topics: { approved: true }).find(1) }