Re: [PATCH 1/2] t/perf: time rev-list with UNINTERESTING commits

[Jeff King <peff@peff.net>]

On Mon, Jan 20, 2014 at 04:31:01PM -0500, Jeff King wrote:

> diff --git a/t/perf/p0001-rev-list.sh b/t/perf/p0001-rev-list.sh
> index 4f71a63..b7258a7 100755
> --- a/t/perf/p0001-rev-list.sh
> +++ b/t/perf/p0001-rev-list.sh
> @@ -14,4 +14,21 @@ test_perf 'rev-list --all --objects' '
>  	git rev-list --all --objects >/dev/null
>  '
>  
> +test_expect_success 'create new unreferenced commit' '
> +	git checkout --detach HEAD &&
> +	echo content >>file &&
> +	git add file &&
> +	git commit -m detached &&
> +	commit=$(git rev-parse --verify HEAD) &&
> +	git checkout -
> +'

This is bad to be touching the repo and assuming it is non-bare. For
some reason I assumed that the perf suite made a copy of the repo, but
it doesn't. If you point to a bare repo via GIT_PERF_REPO, this part of
the test fails.

It's actually enough to demonstrate the problem without changing the
tree at all. So this produces the same numbers, and works everywhere:

diff --git a/t/perf/p0001-rev-list.sh b/t/perf/p0001-rev-list.sh
index b7258a7..16359d5 100755
--- a/t/perf/p0001-rev-list.sh
+++ b/t/perf/p0001-rev-list.sh
@@ -15,12 +15,7 @@ test_perf 'rev-list --all --objects' '
 '
 
 test_expect_success 'create new unreferenced commit' '
-	git checkout --detach HEAD &&
-	echo content >>file &&
-	git add file &&
-	git commit -m detached &&
-	commit=$(git rev-parse --verify HEAD) &&
-	git checkout -
+	commit=$(git commit-tree HEAD^{tree} -p HEAD)
 '
 
 test_perf 'rev-list $commit --not --all' '

It still modifies the test repo, but at least in a fairly innocuous way.

-Peff