From 411241472992301f14da30471a89618bce62c5f5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johel=20Ernesto=20Guerrero=20Pe=C3=B1a?=
 <johelegp@gmail.com>
Date: Sun, 6 Sep 2020 01:10:11 -0400
Subject: [PATCH] test: nonzero denominator

---
 test/unit_test/static/ratio_test.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/test/unit_test/static/ratio_test.cpp b/test/unit_test/static/ratio_test.cpp
index 4284439c..4b4d044f 100644
--- a/test/unit_test/static/ratio_test.cpp
+++ b/test/unit_test/static/ratio_test.cpp
@@ -88,4 +88,10 @@ static_assert(common_ratio(ratio(100, 1), ratio(1, 10)) == ratio(1, 10));
 static_assert(common_ratio(ratio(1), ratio(1, 1, 3)) == ratio(1));
 static_assert(common_ratio(ratio(10, 1, -1), ratio(1, 1, -3)) == ratio(1, 1, -3));
 
+// nonzero denominator
+template <auto> struct require_constant;  // [range.split.view]
+template <auto F> concept constant = requires { typename require_constant<F()>; };
+
+static_assert(!constant<[] { ratio(1, 0); }>);
+
 }  // namespace