diff mercurial/worker.py @ 31696:9d3d56aa1a9f

worker: flush ui buffers before running the worker

a91c6275 introduces flushing ui buffers after a worker finished. If the ui was
not flushed before the worker was started, fork will copy the existing buffers
to the worker. This causes messages issued before the worker started to be
written to the terminal for each worker.

We are now flushing the ui before we start a worker and add an appropriate test
which will fail before this patch.

--- a/mercurial/worker.py	Tue Mar 28 08:40:12 2017 -0700
+++ b/mercurial/worker.py	Tue Mar 28 10:21:38 2017 -0700
@@ -133,6 +133,7 @@
         if problem[0]:
             killworkers()
     oldchldhandler = signal.signal(signal.SIGCHLD, sigchldhandler)
+    ui.flush()
     for pargs in partition(args, workers):
         pid = os.fork()
         if pid == 0: