[commit: ghc] master: testsuite/recomp001: Sleep to ensure that GHC notices file change (769e3ee)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/769e3ee7671f0a038558b591c58ba340c8c09952/ghc

>---------------------------------------------------------------

commit 769e3ee7671f0a038558b591c58ba340c8c09952
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Tue Jan 17 15:48:09 2017 -0500

    testsuite/recomp001: Sleep to ensure that GHC notices file change
    
    Some operating systems (e.g. Darwin) have very poor file timestamp
    resolution.  On these systems GHC often fails to notice that B.hs
    changes in this testsuite, leading to sporatic test failures. Add a
    sleep to ensure the change is noticed.
    
    Test Plan: Validate
    
    Reviewers: ezyang, austin
    
    Subscribers: mpickering, gracjan, thomie
    
    Differential Revision: https://phabricator.haskell.org/D2964


>---------------------------------------------------------------

769e3ee7671f0a038558b591c58ba340c8c09952
 testsuite/tests/driver/recomp001/Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/testsuite/tests/driver/recomp001/Makefile b/testsuite/tests/driver/recomp001/Makefile
index de4f981..a592534 100644
--- a/testsuite/tests/driver/recomp001/Makefile
+++ b/testsuite/tests/driver/recomp001/Makefile
@@ -15,4 +15,7 @@ recomp001: clean
 	cp B1.hs B.hs
 	'$(TEST_HC)' $(TEST_HC_OPTS) --make -v0 C.hs
 	cp B2.hs B.hs
+	# Operating systems with poor timer resolution (e.g. Darwin) need a bit
+	# of time here, lest GHC not realize that the file changed.
+	sleep 1
 	-'$(TEST_HC)' $(TEST_HC_OPTS) --make -v0 C.hs