Make ActiveRecordException descendants args optional

This change allows to instantiate all ActiveRecordError descendant
execption classes without arguments, which might be useful in testing
and is far less surprising than mandatory arguments.

1 files changed, 16 insertions, 0 deletions

diff --git a/activerecord/test/cases/errors_test.rb b/activerecord/test/cases/errors_test.rb
new file mode 100644
index 0000000000..0711a372f2
--- /dev/null
+++ b/activerecord/test/cases/errors_test.rb
@@ -0,0 +1,16 @@
+require_relative "../cases/helper"
+
+class ErrorsTest < ActiveRecord::TestCase
+  def test_can_be_instantiated_with_no_args
+    base = ActiveRecord::ActiveRecordError
+    error_klasses = ObjectSpace.each_object(Class).select { |klass| klass < base }
+
+    error_klasses.each do |error_klass|
+      begin
+        error_klass.new.inspect
+      rescue ArgumentError
+        raise "Instance of #{error_klass} can't be initialized with no arguments"
+      end
+    end
+  end
+end