diff mbox series

[GSOC] describe: enable sparse index for describe

Message ID 20230331154329.121958-1-nanth.raghul@gmail.com (mailing list archive)
State Superseded
Headers show
Series [GSOC] describe: enable sparse index for describe | expand

Commit Message

Raghul Nanth A March 31, 2023, 3:43 p.m. UTC 
Add usage and performance tests for describe

git describe compares the index with the working tree when (and only
when) it is run with the "--dirty" flag. This is done by the
run_diff_index() function. The function has been made aware of the
sparse-index in the series that led to 8d2c3732 (Merge branch
'ld/sparse-diff-blame', 2021-12-21). Hence we can just set the
requires-full-index to false for "describe".

Performance metrics

  Test                                                     HEAD~1            HEAD
  -------------------------------------------------------------------------------------------------
  2000.2: git describe --dirty (full-v3)                   0.08(0.09+0.01)   0.08(0.06+0.03) +0.0%
  2000.3: git describe --dirty (full-v4)                   0.09(0.07+0.03)   0.08(0.05+0.04) -11.1%
  2000.4: git describe --dirty (sparse-v3)                 0.88(0.82+0.06)   0.02(0.01+0.05) -97.7%
  2000.5: git describe --dirty (sparse-v4)                 0.68(0.60+0.08)   0.02(0.02+0.04) -97.1%
  2000.6: echo >>new && git describe --dirty (full-v3)     0.08(0.04+0.05)   0.08(0.05+0.04) +0.0%
  2000.7: echo >>new && git describe --dirty (full-v4)     0.08(0.07+0.03)   0.08(0.05+0.04) +0.0%
  2000.8: echo >>new && git describe --dirty (sparse-v3)   0.75(0.69+0.07)   0.02(0.03+0.03) -97.3%
  2000.9: echo >>new && git describe --dirty (sparse-v4)   0.81(0.73+0.09)   0.02(0.01+0.05) -97.5%

Signed-off-by: Raghul Nanth A <nanth.raghul@gmail.com>
---
 builtin/describe.c                       |  2 ++
 t/perf/p2000-sparse-operations.sh        |  3 +++
 t/t1092-sparse-checkout-compatibility.sh | 30 ++++++++++++++++++++++++
 3 files changed, 35 insertions(+)

Comments

Junio C Hamano March 31, 2023, 4:34 p.m. UTC | #1 
Raghul Nanth A <nanth.raghul@gmail.com> writes:

> Add usage and performance tests for describe

I think the commit is better off without this line.

> git describe compares the index with the working tree when (and only
> when) it is run with the "--dirty" flag. This is done by the
> ...
>
> Signed-off-by: Raghul Nanth A <nanth.raghul@gmail.com>
> ---

Here is where you describe what got changed since the previous
iteration (and following [PATCH v<N>] notational convention would
help people to see which one is meant to be the latest).  These two
are especially helpful when you send more or less identical patches
in quick succession like within a few hours.

Thanks.
diff mbox series

Patch

diff --git a/builtin/describe.c b/builtin/describe.c
index 5b5930f5c8..7ff9b5e4b2 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -654,6 +654,8 @@  int cmd_describe(int argc, const char **argv, const char *prefix)
 			int fd, result;
 
 			setup_work_tree();
+			prepare_repo_settings(the_repository);
+			the_repository->settings.command_requires_full_index = 0;
 			repo_read_index(the_repository);
 			refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
 				      NULL, NULL, NULL);
diff --git a/t/perf/p2000-sparse-operations.sh b/t/perf/p2000-sparse-operations.sh
index 3242cfe91a..db7887470f 100755
--- a/t/perf/p2000-sparse-operations.sh
+++ b/t/perf/p2000-sparse-operations.sh
@@ -43,6 +43,7 @@  test_expect_success 'setup repo and indexes' '
 	done &&
 
 	git sparse-checkout init --cone &&
+	git tag -a v1.0 -m "Final" &&
 	git sparse-checkout set $SPARSE_CONE &&
 	git checkout -b wide $OLD_COMMIT &&
 
@@ -125,5 +126,7 @@  test_perf_on_all git checkout-index -f --all
 test_perf_on_all git update-index --add --remove $SPARSE_CONE/a
 test_perf_on_all "git rm -f $SPARSE_CONE/a && git checkout HEAD -- $SPARSE_CONE/a"
 test_perf_on_all git grep --cached --sparse bogus -- "f2/f1/f1/*"
+test_perf_on_all git describe --dirty
+test_perf_on_all 'echo >>new && git describe --dirty'
 
 test_done
diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index 801919009e..2b46fb2a48 100755
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -1514,6 +1514,36 @@  test_expect_success 'sparse-index is not expanded: stash' '
 	ensure_not_expanded stash pop
 '
 
+test_expect_success 'describe tested on all' '
+	init_repos &&
+
+	# Add tag to be read by describe
+
+	run_on_all git tag -a v1.0 -m "Version 1" &&
+	test_all_match git describe --dirty &&
+	run_on_all rm g &&
+	test_all_match git describe --dirty
+'
+
+
+test_expect_success 'sparse-index is not expanded: describe' '
+	init_repos &&
+
+	# Add tag to be read by describe
+
+	git -C sparse-index tag -a v1.0 -m "Version 1" &&
+
+	ensure_not_expanded describe --dirty &&
+	echo "test" >>sparse-index/g &&
+	ensure_not_expanded describe --dirty &&
+	echo "v1.0-dirty" >actual &&
+
+	# Check describe on dirty work tree
+
+	test_cmp sparse-index-out actual &&
+	ensure_not_expanded describe
+'
+
 test_expect_success 'sparse index is not expanded: diff' '
 	init_repos &&