From 6411aef60952bc0cbad8095d689a6c532f2f31d1 Mon Sep 17 00:00:00 2001
From: Sam Rijs <srijs@airpost.net>
Date: Tue, 17 Jul 2018 20:59:48 +1000
Subject: [PATCH] improve diagnostics for tests with custom return values

fixes #52436
---
 src/libtest/lib.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index 6b547dff912..76e042b063f 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -326,7 +326,14 @@ pub fn test_main_static(tests: &[TestDescAndFn]) {
 /// test is considered a failure. By default, invokes `report()`
 /// and checks for a `0` result.
 pub fn assert_test_result<T: Termination>(result: T) {
-    assert_eq!(result.report(), 0);
+    let code = result.report();
+    assert_eq!(
+        code,
+        0,
+        "the test returned a termination value with a non-zero status code ({}) \
+         which indicates a failure",
+        code
+    );
 }
 
 #[derive(Copy, Clone, Debug)]