[PATCH] test/test-lib.sh: execute basename(1)s lazier in test_expect_equal_file ()

[PATCH] test/test-lib.sh: execute basename(1)s lazier in test_expect_equal_file ()

[Tomi Ollila]

Moved the 2 basename(1) executions to the test failure branch in
test_expect_equal_file ().

The output of basename(1) executions in function test_expect_equal_file ()
are only used when tests fails -- when all tests pass these 2 basename(1)
executions are no longer done at all.
---
 test/test-lib.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/test-lib.sh b/test/test-lib.sh
index bda8a80..397408a 100644
--- a/test/test-lib.sh
+++ b/test/test-lib.sh
@@ -618,15 +618,15 @@ test_expect_equal_file ()
 	error "bug in the test script: not 2 or 3 parameters to test_expect_equal"
 
 	file1="$1"
-	basename1=`basename "$file1"`
 	file2="$2"
-	basename2=`basename "$file2"`
 	if ! test_skip "$test_subtest_name"
 	then
 		if diff -q "$file1" "$file2" >/dev/null ; then
 			test_ok_
 		else
 			testname=$this_test.$test_count
+			basename1=`basename "$file1"`
+			basename2=`basename "$file2"`
 			cp "$file1" "$testname.$basename1"
 			cp "$file2" "$testname.$basename2"
 			test_failure_ "$(diff -u "$testname.$basename1" "$testname.$basename2")"
-- 
2.7.4

Re: [PATCH] test/test-lib.sh: execute basename(1)s lazier in test_expect_equal_file ()

[David Bremner]

Tomi Ollila <tomi.ollila@iki.fi> writes:

> Moved the 2 basename(1) executions to the test failure branch in
> test_expect_equal_file ().
>
> The output of basename(1) executions in function test_expect_equal_file ()
> are only used when tests fails -- when all tests pass these 2 basename(1)
> executions are no longer done at all.

I challenge you to measure the improvement; pushed to master anyway. ;)

d

Re: [PATCH] test/test-lib.sh: execute basename(1)s lazier in test_expect_equal_file ()

[Tomi Ollila]

On Wed, Oct 26 2016, David Bremner <david@tethera.net> wrote:

> Tomi Ollila <tomi.ollila@iki.fi> writes:
>
>> Moved the 2 basename(1) executions to the test failure branch in
>> test_expect_equal_file ().
>>
>> The output of basename(1) executions in function test_expect_equal_file ()
>> are only used when tests fails -- when all tests pass these 2 basename(1)
>> executions are no longer done at all.
>
> I challenge you to measure the improvement; pushed to master anyway. ;)

if 1 fork(2) takes 1 millisecond, then the full test suite runs 1 second
faster (+ some gain from dropping 500 execve(basename) calls).
So notmuch from execute time viewpoint.
(I actually happen to have suitable LD_PRELOAD library which could ne used
to measure execution times so I might accept the challenge ;D)

but this also reduces noise a bit when debugging test suite problems with 
`set -x` -- for human reader that is an improvement... there would be
somuch more to be improved there but oh well... ;/

Tomi

>
> d