create_join_table uses same logic as HABTM reflections

Before this change, create_join_table would not remove the common prefix
in the join table name, unlike ActiveRecord::Reflections. A HABTM
between Music::Artist and Music::Record would use a table
music_artists_records, while create_join table would create
music_artists_music_records.

1 files changed, 24 insertions, 0 deletions

diff --git a/activerecord/test/cases/migration/create_join_table_test.rb b/activerecord/test/cases/migration/create_join_table_test.rb
index 62b60f7f7b..bea9d6b2c9 100644
--- a/activerecord/test/cases/migration/create_join_table_test.rb
+++ b/activerecord/test/cases/migration/create_join_table_test.rb
@@ -119,6 +119,30 @@ module ActiveRecord
 
         assert !connection.tables.include?('artists_musics')
       end
+
+      def test_create_and_drop_join_table_with_common_prefix
+        with_table_cleanup do
+          connection.create_join_table 'audio_artists', 'audio_musics'
+          assert_includes connection.tables, 'audio_artists_musics'
+
+          connection.drop_join_table 'audio_artists', 'audio_musics'
+          assert !connection.tables.include?('audio_artists_musics'), "Should have dropped join table, but didn't"
+        end
+      end
+
+      private
+
+        def with_table_cleanup
+          tables_before = connection.tables
+
+          yield
+        ensure
+          tables_after = connection.tables - tables_before
+
+          tables_after.each do |table|
+            connection.execute "DROP TABLE #{table}"
+          end
+        end
     end
   end
 end