[PATCH] test-logtoprocess: use cat to wait for outputs

Jun Wu quark at fb.com
Thu Feb 16 19:00:47 UTC 2017


# HG changeset patch
# User Jun Wu <quark at fb.com>
# Date 1487270039 28800
#      Thu Feb 16 10:33:59 2017 -0800
# Node ID 9088dc2948690d0668fbaa7bb1f2fe137c40ee5d
# Parent  6e6a461b5b60dc48a9e49cab2f3994b1345531fc
# Available At https://bitbucket.org/quark-zju/hg-draft
#              hg pull https://bitbucket.org/quark-zju/hg-draft -r 9088dc294869
test-logtoprocess: use cat to wait for outputs

Commands started by logtoprocess are running asynchronously. To be able to
test the output, we need to block and wait for the output.

The patch uses "| cat" to wait for such "asynchronous" outputs, to make the
test more reliable. I have also written a short notice at the top, hopefully
people would be aware of the pitfall when changing the test.

diff --git a/tests/test-logtoprocess.t b/tests/test-logtoprocess.t
--- a/tests/test-logtoprocess.t
+++ b/tests/test-logtoprocess.t
@@ -1,2 +1,6 @@
+ATTENTION: logtoprocess runs commands asynchronously. Be sure to append "| cat"
+to hg commands, to wait for the output, if you want to test its output.
+Otherwise the test will be flaky.
+
 Test if logtoprocess correctly captures command-related log calls.
 
@@ -35,7 +39,6 @@ Running a command triggers both a ui.log
 ui.log('commandfinish') call. The foo command also uses ui.log.
 
-Use head to ensure we wait for all lines to be produced, and sort to avoid
-ordering issues between the various processes we spawn:
-  $ hg foo | head -n 17 | sort
+Use sort to avoid ordering issues between the various processes we spawn:
+  $ hg foo | cat | sort
   
   
@@ -67,4 +70,4 @@ Confirm that logging blocked time catche
   > EOF
 
-  $ hg log
+  $ hg log | cat
   uiblocked stdio [0-9]+.[0-9]* ms command [0-9]+.[0-9]* ms (re)


More information about the Mercurial-devel mailing list