runner: more detail when shell check fails

diff --git a/run.py b/run.py
index 8b076fffeb38fb96abbcc248c06cca28e78494f9..436c259a99800571909c7234ce77fc5128ae163b 100755 (executable)
--- a/run.py
+++ b/run.py
@@ -400,7 +400,8 @@ class ShellCheck:
                 return str(self.config["expect"]) == output.decode().strip()
             return True
         except subprocess.CalledProcessError as err:
-            raise TestError(err)
+            raise TestError("Shell command failed: {} -> {}".format(
+                self.config, err.output))
 
 class StatsCheck: