Merge pull request #6874 from robbkidd/rename_sequences_too

Rename default sequence when table is renamed? [AR:postgres]

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -1227,12 +1227,19 @@ def primary_key(table)
       end
 
       # Renames a table.
+      # Also renames a table's primary key sequence if the sequence name matches the
+      # Active Record default.
       #
       # Example:
       #   rename_table('octopuses', 'octopi')
       def rename_table(name, new_name)
         clear_cache!
         execute "ALTER TABLE #{quote_table_name(name)} RENAME TO #{quote_table_name(new_name)}"
+        pk, seq = pk_and_sequence_for(new_name)
+        if seq == "#{name}_#{pk}_seq"
+          new_seq = "#{new_name}_#{pk}_seq"
+          execute "ALTER TABLE #{quote_table_name(seq)} RENAME TO #{quote_table_name(new_seq)}"
+        end
       end
 
       # Adds a new column to the named table.

activerecord/test/cases/migration/rename_table_test.rb

@@ -67,6 +67,19 @@ def test_rename_table_with_an_index
 
         rename_table :octopi, :test_models
       end
+
+      def test_rename_table_for_postgresql_should_also_rename_default_sequence
+        skip 'not supported' unless current_adapter?(:PostgreSQLAdapter)
+
+        rename_table :test_models, :octopi
+
+        con = ActiveRecord::Base.connection
+        pk, seq = con.pk_and_sequence_for('octopi')
+
+        assert_equal "octopi_#{pk}_seq", seq
+
+        rename_table :octopi, :test_models
+      end
     end
   end
 end