1 files changed, 40 insertions, 0 deletions
diff --git a/t/cmop/RT_39001_fix.t b/t/cmop/RT_39001_fix.t
new file mode 100644
index 0000000..a3575e8
--- /dev/null
+++ b/t/cmop/RT_39001_fix.t
@@ -0,0 +1,40 @@
+use strict;
+use warnings;
+use Test::More;
+use Test::Fatal;
+
+use Class::MOP;
+
+=pod
+
+This tests a bug sent via RT #39001
+
+=cut
+
+{
+    package Foo;
+    use metaclass;
+}
+
+like( exception {
+    Foo->meta->superclasses('Foo');
+}, qr/^Recursive inheritance detected/, "error occurs when extending oneself" );
+
+{
+    package Bar;
+    use metaclass;
+}
+
+# reset @ISA, so that calling methods like ->isa won't die (->meta does this
+# if DEBUG_NO_META is set)
+@Foo::ISA = ();
+
+is( exception {
+    Foo->meta->superclasses('Bar');
+}, undef, "regular subclass" );
+
+like( exception {
+    Bar->meta->superclasses('Foo');
+}, qr/^Recursive inheritance detected/, "error occurs when Bar extends Foo, when Foo is a Bar" );
+
+done_testing;