Remove FK together with column in MySQL

Unlike with other databses, MySQL doesn't let you remove the column
if there's a FK on this column.

For better developer experience we want to remove the FK together with
the column.

1 files changed, 10 insertions, 0 deletions

diff --git a/activerecord/test/cases/migration/references_foreign_key_test.rb b/activerecord/test/cases/migration/references_foreign_key_test.rb
index f1ddac1ee2..718b9a0613 100644
--- a/activerecord/test/cases/migration/references_foreign_key_test.rb
+++ b/activerecord/test/cases/migration/references_foreign_key_test.rb
@@ -139,6 +139,16 @@ if ActiveRecord::Base.connection.supports_foreign_keys?
           end
         end
 
+        test "removing column removes foreign key" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, index: true, foreign_key: true
+          end
+
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_column :testings, :testing_parent_id
+          end
+        end
+
         test "foreign key methods respect pluralize_table_names" do
           begin
             original_pluralize_table_names = ActiveRecord::Base.pluralize_table_names