# HG changeset patch
# User Augie Fackler <augie@google.com>
# Date 1496191620 14400
# Node ID c59451e11cbfec538ef7b3dd612ce750020d38a3
# Parent  3ce53a49933423c1112748399be68ae014449c32
tests: make run-tests fail early if no channel is found

I hit a weird corner case in run-tests where a test that caused an
exception to be raised was breaking everything with an unbound
variable error a few lines down because channel was never getting set
in this for loop. By adding an `else` clause to this for loop, we can
explode right away if we can't find a channel and give the developer a
better chance at figuring out what's going on.

diff -r 3ce53a499334 -r c59451e11cbf tests/run-tests.py
--- a/tests/run-tests.py	Sun May 28 15:47:00 2017 -0400
+++ b/tests/run-tests.py	Tue May 30 20:47:00 2017 -0400
@@ -1767,6 +1767,8 @@
                 if not v:
                     channel = n
                     break
+            else:
+                raise ValueError('Could not find output channel')
             channels[channel] = "=" + test.name[5:].split(".")[0]
             try:
                 test(result)