Merge branch 'ps/maintenance-missing-tasks'

Make repository clean-up tasks "gc" can do available to "git
maintenance" front-end.

* ps/maintenance-missing-tasks:
  builtin/maintenance: introduce "rerere-gc" task
  builtin/gc: move rerere garbage collection into separate function
  builtin/maintenance: introduce "worktree-prune" task
  builtin/gc: move pruning of worktrees into a separate function
  builtin/gc: remove global variables where it is trivial to do
  builtin/gc: fix indentation of `cmd_gc()` parameters

Documentation/config/maintenance.adoc

@@ -83,3 +83,20 @@ maintenance.reflog-expire.auto::
 	positive value implies the command should run when the number of
 	expired reflog entries in the "HEAD" reflog is at least the value of
 	`maintenance.loose-objects.auto`. The default value is 100.
+
+maintenance.rerere-gc.auto::
+	This integer config option controls how often the `rerere-gc` task
+	should be run as part of `git maintenance run --auto`. If zero, then
+	the `rerere-gc` task will not run with the `--auto` option. A negative
+	value will force the task to run every time. Otherwise, any positive
+	value implies the command will run when the "rr-cache" directory exists
+	and has at least one entry, regardless of whether it is stale or not.
+	This heuristic may be refined in the future. The default value is 1.
+
+maintenance.worktree-prune.auto::
+	This integer config option controls how often the `worktree-prune` task
+	should be run as part of `git maintenance run --auto`. If zero, then
+	the `worktree-prune` task will not run with the `--auto` option. A
+	negative value will force the task to run every time. Otherwise, a
+	positive value implies the command should run when the number of
+	prunable worktrees exceeds the value. The default value is 1.

Documentation/git-maintenance.adoc

@@ -166,6 +166,14 @@ reflog-expire::
 	The `reflog-expire` task deletes any entries in the reflog older than the
 	expiry threshold. See linkgit:git-reflog[1] for more information.
 
+rerere-gc::
+	The `rerere-gc` task invokes garbage collection for stale entries in
+	the rerere cache. See linkgit:git-rerere[1] for more information.
+
+worktree-prune::
+	The `worktree-prune` task deletes stale or broken worktrees. See
+	linkit:git-worktree[1] for more information.
+
 OPTIONS
 -------
 --auto::

builtin/gc.c

@@ -16,6 +16,7 @@
 #include "builtin.h"
 #include "abspath.h"
 #include "date.h"
+#include "dir.h"
 #include "environment.h"
 #include "hex.h"
 #include "config.h"
@@ -33,6 +34,7 @@
 #include "pack-objects.h"
 #include "path.h"
 #include "reflog.h"
+#include "rerere.h"
 #include "blob.h"
 #include "tree.h"
 #include "promisor-remote.h"
@@ -43,6 +45,7 @@
 #include "hook.h"
 #include "setup.h"
 #include "trace2.h"
+#include "worktree.h"
 
 #define FAILED_RUN "failed to run %s"
 
@@ -52,15 +55,9 @@ static const char * const builtin_gc_usage[] = {
 };
 
 static timestamp_t gc_log_expire_time;
-
 static struct strvec repack = STRVEC_INIT;
-static struct strvec prune = STRVEC_INIT;
-static struct strvec prune_worktrees = STRVEC_INIT;
-static struct strvec rerere = STRVEC_INIT;
-
 static struct tempfile *pidfile;
 static struct lock_file log_lock;
-
 static struct string_list pack_garbage = STRING_LIST_INIT_DUP;
 
 static void clean_pack_garbage(void)
@@ -339,6 +336,94 @@ static int maintenance_task_reflog_expire(struct maintenance_run_opts *opts UNUS
 	return run_command(&cmd);
 }
 
+static int maintenance_task_worktree_prune(struct maintenance_run_opts *opts UNUSED,
+					   struct gc_config *cfg)
+{
+	struct child_process prune_worktrees_cmd = CHILD_PROCESS_INIT;
+
+	prune_worktrees_cmd.git_cmd = 1;
+	strvec_pushl(&prune_worktrees_cmd.args, "worktree", "prune", "--expire", NULL);
+	strvec_push(&prune_worktrees_cmd.args, cfg->prune_worktrees_expire);
+
+	return run_command(&prune_worktrees_cmd);
+}
+
+static int worktree_prune_condition(struct gc_config *cfg)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int should_prune = 0, limit = 1;
+	timestamp_t expiry_date;
+	struct dirent *d;
+	DIR *dir = NULL;
+
+	git_config_get_int("maintenance.worktree-prune.auto", &limit);
+	if (limit <= 0) {
+		should_prune = limit < 0;
+		goto out;
+	}
+
+	if (parse_expiry_date(cfg->prune_worktrees_expire, &expiry_date))
+		goto out;
+
+	dir = opendir(repo_git_path_replace(the_repository, &buf, "worktrees"));
+	if (!dir)
+		goto out;
+
+	while (limit && (d = readdir_skip_dot_and_dotdot(dir))) {
+		char *wtpath;
+		strbuf_reset(&buf);
+		if (should_prune_worktree(d->d_name, &buf, &wtpath, expiry_date))
+			limit--;
+		free(wtpath);
+	}
+
+	should_prune = !limit;
+
+out:
+	if (dir)
+		closedir(dir);
+	strbuf_release(&buf);
+	return should_prune;
+}
+
+static int maintenance_task_rerere_gc(struct maintenance_run_opts *opts UNUSED,
+				      struct gc_config *cfg UNUSED)
+{
+	struct child_process rerere_cmd = CHILD_PROCESS_INIT;
+	rerere_cmd.git_cmd = 1;
+	strvec_pushl(&rerere_cmd.args, "rerere", "gc", NULL);
+	return run_command(&rerere_cmd);
+}
+
+static int rerere_gc_condition(struct gc_config *cfg UNUSED)
+{
+	struct strbuf path = STRBUF_INIT;
+	int should_gc = 0, limit = 1;
+	DIR *dir = NULL;
+
+	git_config_get_int("maintenance.rerere-gc.auto", &limit);
+	if (limit <= 0) {
+		should_gc = limit < 0;
+		goto out;
+	}
+
+	/*
+	 * We skip garbage collection in case we either have no "rr-cache"
+	 * directory or when it doesn't contain at least one entry.
+	 */
+	repo_git_path_replace(the_repository, &path, "rr-cache");
+	dir = opendir(path.buf);
+	if (!dir)
+		goto out;
+	should_gc = !!readdir_skip_dot_and_dotdot(dir);
+
+out:
+	strbuf_release(&path);
+	if (dir)
+		closedir(dir);
+	return should_gc;
+}
+
 static int too_many_loose_objects(struct gc_config *cfg)
 {
 	/*
@@ -728,9 +813,9 @@ static void gc_before_repack(struct maintenance_run_opts *opts,
 }
 
 int cmd_gc(int argc,
-const char **argv,
+	   const char **argv,
-const char *prefix,
+	   const char *prefix,
-struct repository *repo UNUSED)
+	   struct repository *repo UNUSED)
 {
 	int aggressive = 0;
 	int quiet = 0;
@@ -740,7 +825,6 @@ struct repository *repo UNUSED)
 	int daemonized = 0;
 	int keep_largest_pack = -1;
 	timestamp_t dummy;
-	struct child_process rerere_cmd = CHILD_PROCESS_INIT;
 	struct maintenance_run_opts opts = MAINTENANCE_RUN_OPTS_INIT;
 	struct gc_config cfg = GC_CONFIG_INIT;
 	const char *prune_expire_sentinel = "sentinel";
@@ -779,9 +863,6 @@ struct repository *repo UNUSED)
 					 builtin_gc_usage, builtin_gc_options);
 
 	strvec_pushl(&repack, "repack", "-d", "-l", NULL);
-	strvec_pushl(&prune, "prune", "--expire", NULL);
-	strvec_pushl(&prune_worktrees, "worktree", "prune", "--expire", NULL);
-	strvec_pushl(&rerere, "rerere", "gc", NULL);
 
 	gc_config(&cfg);
 
@@ -907,34 +988,27 @@ struct repository *repo UNUSED)
 		if (cfg.prune_expire) {
 			struct child_process prune_cmd = CHILD_PROCESS_INIT;
 
+			strvec_pushl(&prune_cmd.args, "prune", "--expire", NULL);
 			/* run `git prune` even if using cruft packs */
-			strvec_push(&prune, cfg.prune_expire);
+			strvec_push(&prune_cmd.args, cfg.prune_expire);
 			if (quiet)
-				strvec_push(&prune, "--no-progress");
+				strvec_push(&prune_cmd.args, "--no-progress");
 			if (repo_has_promisor_remote(the_repository))
-				strvec_push(&prune,
+				strvec_push(&prune_cmd.args,
 					    "--exclude-promisor-objects");
 			prune_cmd.git_cmd = 1;
-			strvec_pushv(&prune_cmd.args, prune.v);
+
 			if (run_command(&prune_cmd))
-				die(FAILED_RUN, prune.v[0]);
+				die(FAILED_RUN, prune_cmd.args.v[0]);
 		}
 	}
 
-	if (cfg.prune_worktrees_expire) {
+	if (cfg.prune_worktrees_expire &&
-		struct child_process prune_worktrees_cmd = CHILD_PROCESS_INIT;
+	    maintenance_task_worktree_prune(&opts, &cfg))
+		die(FAILED_RUN, "worktree");
 
-		strvec_push(&prune_worktrees, cfg.prune_worktrees_expire);
+	if (maintenance_task_rerere_gc(&opts, &cfg))
-		prune_worktrees_cmd.git_cmd = 1;
+		die(FAILED_RUN, "rerere");
-		strvec_pushv(&prune_worktrees_cmd.args, prune_worktrees.v);
-		if (run_command(&prune_worktrees_cmd))
-			die(FAILED_RUN, prune_worktrees.v[0]);
-	}
-
-	rerere_cmd.git_cmd = 1;
-	strvec_pushv(&rerere_cmd.args, rerere.v);
-	if (run_command(&rerere_cmd))
-		die(FAILED_RUN, rerere.v[0]);
 
 	report_garbage = report_pack_garbage;
 	reprepare_packed_git(the_repository);
@@ -1467,6 +1541,8 @@ enum maintenance_task_label {
 	TASK_COMMIT_GRAPH,
 	TASK_PACK_REFS,
 	TASK_REFLOG_EXPIRE,
+	TASK_WORKTREE_PRUNE,
+	TASK_RERERE_GC,
 
 	/* Leave as final value */
 	TASK__COUNT
@@ -1508,6 +1584,16 @@ static struct maintenance_task tasks[] = {
 		maintenance_task_reflog_expire,
 		reflog_expire_condition,
 	},
+	[TASK_WORKTREE_PRUNE] = {
+		"worktree-prune",
+		maintenance_task_worktree_prune,
+		worktree_prune_condition,
+	},
+	[TASK_RERERE_GC] = {
+		"rerere-gc",
+		maintenance_task_rerere_gc,
+		rerere_gc_condition,
+	},
 };
 
 static int compare_tasks_by_selection(const void *a_, const void *b_)

t/t7900-maintenance.sh

@@ -493,6 +493,121 @@ test_expect_success 'reflog-expire task --auto only packs when exceeding limits'
 	test_subcommand git reflog expire --all <reflog-expire-auto.txt
 '
 
+test_expect_worktree_prune () {
+	negate=
+	if test "$1" = "!"
+	then
+		negate="!"
+		shift
+	fi
+
+	rm -f "worktree-prune.txt" &&
+	GIT_TRACE2_EVENT="$(pwd)/worktree-prune.txt" "$@" &&
+	test_subcommand $negate git worktree prune --expire 3.months.ago <worktree-prune.txt
+}
+
+test_expect_success 'worktree-prune task without --auto always prunes' '
+	test_expect_worktree_prune git maintenance run --task=worktree-prune
+'
+
+test_expect_success 'worktree-prune task --auto only prunes with prunable worktree' '
+	test_expect_worktree_prune ! git maintenance run --auto --task=worktree-prune &&
+	mkdir .git/worktrees &&
+	: >.git/worktrees/abc &&
+	test_expect_worktree_prune git maintenance run --auto --task=worktree-prune
+'
+
+test_expect_success 'worktree-prune task with --auto honors maintenance.worktree-prune.auto' '
+	# A negative value should always prune.
+	test_expect_worktree_prune git -c maintenance.worktree-prune.auto=-1 maintenance run --auto --task=worktree-prune &&
+
+	mkdir .git/worktrees &&
+	: >.git/worktrees/first &&
+	: >.git/worktrees/second &&
+	: >.git/worktrees/third &&
+
+	# Zero should never prune.
+	test_expect_worktree_prune ! git -c maintenance.worktree-prune.auto=0 maintenance run --auto --task=worktree-prune &&
+	# A positive value should require at least this many prunable worktrees.
+	test_expect_worktree_prune ! git -c maintenance.worktree-prune.auto=4 maintenance run --auto --task=worktree-prune &&
+	test_expect_worktree_prune git -c maintenance.worktree-prune.auto=3 maintenance run --auto --task=worktree-prune
+'
+
+test_expect_success 'worktree-prune task with --auto honors maintenance.worktree-prune.auto' '
+	# A negative value should always prune.
+	test_expect_worktree_prune git -c maintenance.worktree-prune.auto=-1 maintenance run --auto --task=worktree-prune &&
+
+	mkdir .git/worktrees &&
+	: >.git/worktrees/first &&
+	: >.git/worktrees/second &&
+	: >.git/worktrees/third &&
+
+	# Zero should never prune.
+	test_expect_worktree_prune ! git -c maintenance.worktree-prune.auto=0 maintenance run --auto --task=worktree-prune &&
+	# A positive value should require at least this many prunable worktrees.
+	test_expect_worktree_prune ! git -c maintenance.worktree-prune.auto=4 maintenance run --auto --task=worktree-prune &&
+	test_expect_worktree_prune git -c maintenance.worktree-prune.auto=3 maintenance run --auto --task=worktree-prune
+'
+
+test_expect_success 'worktree-prune task honors gc.worktreePruneExpire' '
+	git worktree add worktree &&
+	rm -rf worktree &&
+
+	rm -f worktree-prune.txt &&
+	GIT_TRACE2_EVENT="$(pwd)/worktree-prune.txt" git -c gc.worktreePruneExpire=1.week.ago maintenance run --auto --task=worktree-prune &&
+	test_subcommand ! git worktree prune --expire 1.week.ago <worktree-prune.txt &&
+	test_path_is_dir .git/worktrees/worktree &&
+
+	rm -f worktree-prune.txt &&
+	GIT_TRACE2_EVENT="$(pwd)/worktree-prune.txt" git -c gc.worktreePruneExpire=now maintenance run --auto --task=worktree-prune &&
+	test_subcommand git worktree prune --expire now <worktree-prune.txt &&
+	test_path_is_missing .git/worktrees/worktree
+'
+
+test_expect_rerere_gc () {
+	negate=
+	if test "$1" = "!"
+	then
+		negate="!"
+		shift
+	fi
+
+	rm -f "rerere-gc.txt" &&
+	GIT_TRACE2_EVENT="$(pwd)/rerere-gc.txt" "$@" &&
+	test_subcommand $negate git rerere gc <rerere-gc.txt
+}
+
+test_expect_success 'rerere-gc task without --auto always collects garbage' '
+	test_expect_rerere_gc git maintenance run --task=rerere-gc
+'
+
+test_expect_success 'rerere-gc task with --auto only prunes with prunable entries' '
+	test_when_finished "rm -rf .git/rr-cache" &&
+	test_expect_rerere_gc ! git maintenance run --auto --task=rerere-gc &&
+	mkdir .git/rr-cache &&
+	test_expect_rerere_gc ! git maintenance run --auto --task=rerere-gc &&
+	: >.git/rr-cache/entry &&
+	test_expect_rerere_gc git maintenance run --auto --task=rerere-gc
+'
+
+test_expect_success 'rerere-gc task with --auto honors maintenance.rerere-gc.auto' '
+	test_when_finished "rm -rf .git/rr-cache" &&
+
+	# A negative value should always prune.
+	test_expect_rerere_gc git -c maintenance.rerere-gc.auto=-1 maintenance run --auto --task=rerere-gc &&
+
+	# A positive value prunes when there is at least one entry.
+	test_expect_rerere_gc ! git -c maintenance.rerere-gc.auto=9000 maintenance run --auto --task=rerere-gc &&
+	mkdir .git/rr-cache &&
+	test_expect_rerere_gc ! git -c maintenance.rerere-gc.auto=9000 maintenance run --auto --task=rerere-gc &&
+	: >.git/rr-cache/entry-1 &&
+	test_expect_rerere_gc git -c maintenance.rerere-gc.auto=9000 maintenance run --auto --task=rerere-gc &&
+
+	# Zero should never prune.
+	: >.git/rr-cache/entry-1 &&
+	test_expect_rerere_gc ! git -c maintenance.rerere-gc.auto=0 maintenance run --auto --task=rerere-gc
+'
+
 test_expect_success '--auto and --schedule incompatible' '
 	test_must_fail git maintenance run --auto --schedule=daily 2>err &&
 	test_grep "at most one" err