fk: raise for invalid :on_update / :on_delete values

activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb

@@ -104,9 +104,14 @@ FOREIGN KEY (#{quote_column_name(o.column)})
 
           def action_sql(action, dependency)
             case dependency
-              when :nullify then "ON #{action} SET NULL"
-              when :cascade  then "ON #{action} CASCADE"
-              when :restrict then "ON #{action} RESTRICT"
+            when :nullify then "ON #{action} SET NULL"
+            when :cascade  then "ON #{action} CASCADE"
+            when :restrict then "ON #{action} RESTRICT"
+            else
+              raise ArgumentError, <<-MSG
+'#{dependency}' is not supported for :on_update or :on_delete.
+Supported values are: :nullify, :cascade, :restrict
+              MSG
             end
           end
       end

activerecord/test/cases/migration/foreign_key_test.rb

@@ -126,6 +126,16 @@ module ActiveRecord
         assert_equal :nullify, fk.on_delete
       end
 
+      def test_on_update_and_on_delete_raises_with_invalid_values
+        assert_raises ArgumentError do
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :invalid
+        end
+
+        assert_raises ArgumentError do
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :invalid
+        end
+      end
+
       def test_add_foreign_key_with_on_update
         @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :nullify