Add test for PR11811 (disable a positivity check)

1 files changed, 13 insertions, 0 deletions

diff --git a/test-suite/bugs/closed/bug_11811.v b/test-suite/bugs/closed/bug_11811.v
new file mode 100644
index 0000000000..a73494b630
--- /dev/null
+++ b/test-suite/bugs/closed/bug_11811.v
@@ -0,0 +1,13 @@
+
+Unset Positivity Checking.
+
+Inductive foo : Type -> Type :=
+| bar : foo (foo unit)
+| baz : foo nat.
+
+Definition toto : forall A, foo A -> {A = foo unit} + {A = nat}.
+Proof.
+  intros A x. destruct x; intuition.
+Defined.
+
+Check (eq_refl : toto _ baz = right eq_refl).