scalar reconfigure: add --no-maintenance option

When users want to enable the latest and greatest configuration options
recommended by Scalar after a Git upgrade, 'scalar reconfigure --all' is
a great option that iterates over all repos in the multi-valued
'scalar.repos' config key.

However, this feature previously forced users to enable background
maintenance. In some environments this is not preferred.

Add a new --[no-]maintenance option to 'scalar reconfigure' that avoids
running 'git maintenance start' on these enlistments.

Signed-off-by: Derrick Stolee <stolee@gmail.com>

Author: derrickstolee

Documentation/scalar.adoc

@@ -14,7 +14,7 @@ scalar list
 scalar register [--[no-]maintenance] [<enlistment>]
 scalar unregister [<enlistment>]
 scalar run ( all | config | commit-graph | fetch | loose-objects | pack-files ) [<enlistment>]
-scalar reconfigure [ --all | <enlistment> ]
+scalar reconfigure [--[no-]maintenance] [ --all | <enlistment> ]
 scalar diagnose [<enlistment>]
 scalar delete <enlistment>
 
@@ -160,8 +160,16 @@ After a Scalar upgrade, or when the configuration of a Scalar enlistment
 was somehow corrupted or changed by mistake, this subcommand allows to
 reconfigure the enlistment.
 
-With the `--all` option, all enlistments currently registered with Scalar
-will be reconfigured. Use this option after each Scalar upgrade.
+--all::
+	When `--all` is specified, reconfigure all enlistments currently
+	registered with Scalar by the `scalar.repo` config key. Use this
+	option after each upgrade to get the latest features.
+
+--[no-]maintenance::
+	By default, Scalar configures the enlistment to use Git's
+	background maintenance feature. Use the `--no-maintenance` to skip
+	this configuration and leave the repositories in whatever state is
+	currently configured.
 
 Diagnose
 ~~~~~~~~

scalar.c

@@ -670,14 +670,16 @@ static int remove_deleted_enlistment(struct strbuf *path)
 
 static int cmd_reconfigure(int argc, const char **argv)
 {
-	int all = 0;
+	int all = 0, maintenance = 1;
 	struct option options[] = {
 		OPT_BOOL('a', "all", &all,
 			 N_("reconfigure all registered enlistments")),
+		OPT_BOOL(0, "maintenance", &maintenance,
+			 N_("specify if background maintenance should be enabled")),
 		OPT_END(),
 	};
 	const char * const usage[] = {
-		N_("scalar reconfigure [--all | <enlistment>]"),
+		N_("scalar reconfigure [--[no-]maintenance] [--all | <enlistment>]"),
 		NULL
 	};
 	struct string_list scalar_repos = STRING_LIST_INIT_DUP;
@@ -761,7 +763,8 @@ static int cmd_reconfigure(int argc, const char **argv)
 		the_repository = old_repo;
 		repo_clear(&r);
 
-		if (toggle_maintenance(1) >= 0)
+		if (maintenance &&
+		    toggle_maintenance(1) >= 0)
 			succeeded = 1;
 
 loop_end:

t/t9210-scalar.sh

@@ -210,7 +210,12 @@ test_expect_success 'scalar reconfigure' '
 	GIT_TRACE2_EVENT="$(pwd)/reconfigure" scalar reconfigure -a &&
 	test_path_is_file one/src/cron.txt &&
 	test true = "$(git -C one/src config core.preloadIndex)" &&
-	test_subcommand git maintenance start <reconfigure
+	test_subcommand git maintenance start <reconfigure &&
+	test_subcommand ! git maintenance unregister --force <reconfigure &&
+
+	GIT_TRACE2_EVENT="$(pwd)/reconfigure-maint" scalar reconfigure --no-maintenance -a &&
+	test_subcommand ! git maintenance start <reconfigure-maint &&
+	test_subcommand ! git maintenance unregister --force <reconfigure-maint
 '
 
 test_expect_success 'scalar reconfigure --all with includeIf.onbranch' '