pr7712: add a test

1 files changed, 20 insertions, 0 deletions

diff --git a/testsuite/tests/typing-misc/pr7712.ml b/testsuite/tests/typing-misc/pr7712.ml
new file mode 100644
index 0000000000..09ffb4d297
--- /dev/null
+++ b/testsuite/tests/typing-misc/pr7712.ml
@@ -0,0 +1,20 @@
+(* TEST
+   * expect
+*)
+
+type 'a or_error = string
+
+type ('a, 'b) t_ =
+  | Bar : ('a, 'a or_error) t_
+
+type 'a t = ('a, 'a) t_
+
+let f : type a. a t -> a t = function
+  | Bar -> Bar
+;;
+[%%expect{|
+type 'a or_error = string
+type ('a, 'b) t_ = Bar : ('a, 'a or_error) t_
+type 'a t = ('a, 'a) t_
+val f : 'a t -> 'a t = <fun>
+|}];;