# HG changeset patch
# User Bryan O'Sullivan <bryano@fb.com>
# Date 1453489213 28800
# Node ID a6833e464b070c2f51edff8d6e55be79f5d9db22
# Parent  6bc2299cc12f95faa295dc93ada6a862c7be59e6
run-tests: "fix" race condition in race condition fix

Laurent's commit 3203dfe341f9 still suffers from a race: by the
time the "job" function tries to assign to channels[channel], that
list has been truncated to empty.  The result is that every job
thread raises an IndexError.

Earlier, I tried an approach of correctly locking channels, but
that caused run-tests to hang on KeyboardInterrupt sometimes.

This approach is strictly hackier, but seems to actually work
reliably.

diff -r 6bc2299cc12f -r a6833e464b07 tests/run-tests.py
--- a/tests/run-tests.py	Fri Jan 22 20:32:47 2016 +0000
+++ b/tests/run-tests.py	Fri Jan 22 11:00:13 2016 -0800
@@ -1526,13 +1526,16 @@
             channels[channel] = "=" + test.name[5:].split(".")[0]
             try:
                 test(result)
-                channels[channel] = ''
                 done.put(None)
             except KeyboardInterrupt:
-                channels[channel] = ''
+                pass
             except: # re-raises
                 done.put(('!', test, 'run-test raised an error, see traceback'))
                 raise
+            try:
+                channels[channel] = ''
+            except IndexError:
+                pass
 
         def stat():
             count = 0