Merge pull request #34197 from schneems/schneems/symbol-hash-respond_to

ActiveRecord#respond_to? No longer allocates strings

3 files changed, 11 insertions, 12 deletions

diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index 3c785180e1..eeb88e4b7a 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -261,21 +261,14 @@ module ActiveRecord
     def respond_to?(name, include_private = false)
       return false unless super
 
-      case name
-      when :to_partial_path
-        name = "to_partial_path"
-      when :to_model
-        name = "to_model"
-      else
-        name = name.to_s
-      end
-
       # If the result is true then check for the select case.
       # For queries selecting a subset of columns, return false for unselected columns.
       # We check defined?(@attributes) not to issue warnings if called on objects that
       # have been allocated but not yet initialized.
-      if defined?(@attributes) && self.class.column_names.include?(name)
-        return has_attribute?(name)
+      if defined?(@attributes)
+        if name = self.class.symbol_column_to_string(name.to_sym)
+          return has_attribute?(name)
+        end
       end
 
       true
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index 5a4a1fb969..c50a420432 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -388,6 +388,11 @@ module ActiveRecord
         @column_names ||= columns.map(&:name)
       end
 
+      def symbol_column_to_string(name_symbol) # :nodoc:
+        @symbol_column_to_string_name_hash ||= column_names.index_by(&:to_sym)
+        @symbol_column_to_string_name_hash[name_symbol]
+      end
+
       # Returns an array of column objects where the primary id, all columns ending in "_id" or "_count",
       # and columns used for single table inheritance have been removed.
       def content_columns
@@ -477,6 +482,7 @@ module ActiveRecord
         def reload_schema_from_cache
           @arel_table = nil
           @column_names = nil
+          @symbol_column_to_string_name_hash = nil
           @attribute_types = nil
           @content_columns = nil
           @default_attributes = nil
diff --git a/activerecord/lib/active_record/nested_attributes.rb b/activerecord/lib/active_record/nested_attributes.rb
index 50767ee93f..8b9098df6c 100644
--- a/activerecord/lib/active_record/nested_attributes.rb
+++ b/activerecord/lib/active_record/nested_attributes.rb
@@ -426,7 +426,7 @@ module ActiveRecord
             existing_record.assign_attributes(assignable_attributes)
             association(association_name).initialize_attributes(existing_record)
           else
-            method = "build_#{association_name}"
+            method = :"build_#{association_name}"
             if respond_to?(method)
               send(method, assignable_attributes)
             else