From df326a1d597c28f4976e5b111306465ba1c76f67 Mon Sep 17 00:00:00 2001
From: Rolf Bjarne Kvinge <rolf@xamarin.com>
Date: Wed, 15 Jun 2016 16:52:24 -0700
Subject: [PATCH] [xharness] Throw a helpful exception instead of NRE when a
 simulator can't be found.

---
 tests/xharness/AppRunner.cs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/xharness/AppRunner.cs b/tests/xharness/AppRunner.cs
index edbb713401..c311c4e469 100644
--- a/tests/xharness/AppRunner.cs
+++ b/tests/xharness/AppRunner.cs
@@ -142,6 +142,8 @@ namespace xharness
 					candidate = data;
 				}
 			}
+			if (candidate == null)
+				throw new Exception ($"Could not find simulator for runtime={simulator_runtime} and device type={simulator_devicetype}.");
 			if (simulators == null)
 				simulators = new SimDevice [] { candidate };