[PATCH 2/2] config: let feature.experimental imply gc.cruftPacks=true

From

Emily Shaffer <emilyshaffer@google.com>

Date

Aug 3, 2022, 20:57 UTC

Message-ID

<20220803205721.3686361-3-emilyshaffer@google.com>

In-Reply-To

<20220803205721.3686361-1-emilyshaffer@google.com>

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
---
 Documentation/config/feature.txt |  2 ++
 builtin/gc.c                     |  6 ++++++
 t/t6500-gc.sh                    | 35 ++++++++++++++++++++++++++++++++
 3 files changed, 43 insertions(+)

diff --git a/Documentation/config/feature.txt b/Documentation/config/feature.txt
index cdecd04e5b..f029c422be 100644
--- a/Documentation/config/feature.txt
+++ b/Documentation/config/feature.txt
@@ -14,6 +14,8 @@ feature.experimental::
 +
 * `fetch.negotiationAlgorithm=skipping` may improve fetch negotiation times by
 skipping more commits at a time, reducing the number of round trips.
+* `gc.cruftPacks=true` reduces disk space used by unreachable objects during
+garbage collection.
 
 feature.manyFiles::
 	Enable config options that optimize for repos with many files in the
diff --git a/builtin/gc.c b/builtin/gc.c
index eeff2b760e..919cc508c5 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -136,6 +136,7 @@ static int gc_config_is_timestamp_never(const char *var)
 static void gc_config(void)
 {
 	const char *value;
+	int experimental = 0;
 
 	if (!git_config_get_value("gc.packrefs", &value)) {
 		if (value && !strcmp(value, "notbare"))
@@ -148,6 +149,11 @@ static void gc_config(void)
 	    gc_config_is_timestamp_never("gc.reflogexpireunreachable"))
 		prune_reflogs = 0;
 
+	/* feature.experimental implies gc.cruftPacks=true */
+	git_config_get_bool("feature.experimental", &experimental);
+	if (experimental)
+		cruft_packs = 1;
+
 	git_config_get_int("gc.aggressivewindow", &aggressive_window);
 	git_config_get_int("gc.aggressivedepth", &aggressive_depth);
 	git_config_get_int("gc.auto", &gc_auto_threshold);
diff --git a/t/t6500-gc.sh b/t/t6500-gc.sh
index e4c2c3583d..4ab6750111 100755
--- a/t/t6500-gc.sh
+++ b/t/t6500-gc.sh
@@ -238,6 +238,41 @@ test_expect_success 'gc.cruftPacks=true generates a cruft pack' '
 	)
 '
 
+test_expect_success 'feature.experimental=true generates a cruft pack' '
+	git init crufts &&
+	test_when_finished "rm -fr crufts" &&
+	(
+		cd crufts &&
+		test_commit base &&
+
+		test_commit --no-tag foo &&
+		test_commit --no-tag bar &&
+		git reset HEAD^^ &&
+
+		git -c feature.experimental=true gc &&
+
+		cruft=$(basename $(ls .git/objects/pack/pack-*.mtimes) .mtimes) &&
+		test_path_is_file .git/objects/pack/$cruft.pack
+	)
+'
+
+test_expect_success 'feature.experimental=false allows explicit cruft packs' '
+	git init crufts &&
+	test_when_finished "rm -fr crufts" &&
+	(
+		cd crufts &&
+		test_commit base &&
+
+		test_commit --no-tag foo &&
+		test_commit --no-tag bar &&
+		git reset HEAD^^ &&
+
+		git -c gc.cruftPacks=true -c feature.experimental=false gc &&
+		cruft=$(basename $(ls .git/objects/pack/pack-*.mtimes) .mtimes) &&
+		test_path_is_file .git/objects/pack/$cruft.pack
+	)
+'
+
 run_and_wait_for_auto_gc () {
 	# We read stdout from gc for the side effect of waiting until the
 	# background gc process exits, closing its fd 9.  Furthermore, the

-- 
2.37.1.455.g008518b4e5-goog