hook: allow disabling config hooks

Hooks specified via configs are always enabled, however users
might want to disable them without removing from the config,
like locally disabling a global hook.

Add a hook.<name>.enabled config which defaults to true and
can be optionally set for each configured hook.

Suggested-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/hook.c b/hook.c
index 8a9b405f76..35c24bf33d 100644
--- a/hook.c
+++ b/hook.c
@@ -164,6 +164,21 @@ static int hook_config_lookup_all(const char *key, const char *value,
 		char *old = strmap_put(&data->commands, hook_name,
 				       xstrdup(value));
 		free(old);
+	} else if (!strcmp(subkey, "enabled")) {
+		switch (git_parse_maybe_bool(value)) {
+		case 0: /* disabled */
+			if (!unsorted_string_list_lookup(&data->disabled_hooks,
+							 hook_name))
+				string_list_append(&data->disabled_hooks,
+						   hook_name);
+			break;
+		case 1: /* enabled: undo a prior disabled entry */
+			unsorted_string_list_remove(&data->disabled_hooks,
+						    hook_name);
+			break;
+		default:
+			break; /* ignore unrecognised values */
+		}
 	}
 
 	free(hook_name);
@@ -216,6 +231,11 @@ static void build_hook_config_map(struct repository *r, struct strmap *cache)
 			const char *hname = hook_names->items[i].string;
 			char *command;
 
+			/* filter out disabled hooks */
+			if (unsorted_string_list_lookup(&cb_data.disabled_hooks,
+							hname))
+				continue;
+
 			command = strmap_get(&cb_data.commands, hname);
 			if (!command)
 				die(_("'hook.%s.command' must be configured or "