[PATCH v2 3/8] hook: add "git hook list" command

From

Adrian Ratiu <adrian.ratiu@collabora.com>

Date

Feb 18, 2026, 22:23 UTC

Message-ID

<20260218222352.55393-4-adrian.ratiu@collabora.com>

In-Reply-To

<20260218222352.55393-1-adrian.ratiu@collabora.com>

From: Emily Shaffer <emilyshaffer@google.com>

Further commits will expand on this, e.g. by adding a -z output mode.

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
---
 Documentation/git-hook.adoc |  5 ++++
 builtin/hook.c              | 60 +++++++++++++++++++++++++++++++++++++
 hook.c                      | 17 ++---------
 hook.h                      | 24 ++++++++++++++-
 t/t1800-hook.sh             | 22 ++++++++++++++
 5 files changed, 112 insertions(+), 16 deletions(-)

diff --git a/Documentation/git-hook.adoc b/Documentation/git-hook.adoc
index f6cc72d2ca..eb0ffcb8a9 100644
--- a/Documentation/git-hook.adoc
+++ b/Documentation/git-hook.adoc
@@ -9,6 +9,7 @@ SYNOPSIS
 --------
 [verse]
 'git hook' run [--ignore-missing] [--to-stdin=<path>] <hook-name> [-- <hook-args>]
+'git hook' list <hook-name>
 
 DESCRIPTION
 -----------
@@ -28,6 +29,10 @@ Any positional arguments to the hook should be passed after a
 mandatory `--` (or `--end-of-options`, see linkgit:gitcli[7]). See
 linkgit:githooks[5] for arguments hooks might expect (if any).
 
+list::
+	Print a list of hooks which will be run on `<hook-name>` event. If no
+	hooks are configured for that event, print a warning and return 1.
+
 OPTIONS
 -------
 
diff --git a/builtin/hook.c b/builtin/hook.c
index 7afec380d2..51660c4941 100644
--- a/builtin/hook.c
+++ b/builtin/hook.c
@@ -6,12 +6,16 @@
 #include "hook.h"
 #include "parse-options.h"
 #include "strvec.h"
+#include "abspath.h"
 
 #define BUILTIN_HOOK_RUN_USAGE \
 	N_("git hook run [--ignore-missing] [--to-stdin=<path>] <hook-name> [-- <hook-args>]")
+#define BUILTIN_HOOK_LIST_USAGE \
+	N_("git hook list <hook-name>")
 
 static const char * const builtin_hook_usage[] = {
 	BUILTIN_HOOK_RUN_USAGE,
+	BUILTIN_HOOK_LIST_USAGE,
 	NULL
 };
 
@@ -20,6 +24,61 @@ static const char * const builtin_hook_run_usage[] = {
 	NULL
 };
 
+static int list(int argc, const char **argv, const char *prefix,
+		 struct repository *repo)
+{
+	static const char *const builtin_hook_list_usage[] = {
+		BUILTIN_HOOK_LIST_USAGE,
+		NULL
+	};
+	struct string_list *head;
+	struct string_list_item *item;
+	const char *hookname = NULL;
+	int ret = 0;
+
+	struct option list_options[] = {
+		OPT_END(),
+	};
+
+	argc = parse_options(argc, argv, prefix, list_options,
+			     builtin_hook_list_usage, 0);
+
+	/*
+	 * The only unnamed argument provided should be the hook-name; if we add
+	 * arguments later they probably should be caught by parse_options.
+	 */
+	if (argc != 1)
+		usage_msg_opt(_("You must specify a hook event name to list."),
+			      builtin_hook_list_usage, list_options);
+
+	hookname = argv[0];
+
+	head = list_hooks(repo, hookname, NULL);
+
+	if (!head->nr) {
+		warning(_("No hooks found for event '%s'"), hookname);
+		ret = 1; /* no hooks found */
+		goto cleanup;
+	}
+
+	for_each_string_list_item(item, head) {
+		struct hook *h = item->util;
+
+		switch (h->kind) {
+		case HOOK_TRADITIONAL:
+			printf("%s\n", _("hook from hookdir"));
+			break;
+		default:
+			BUG("unknown hook kind");
+		}
+	}
+
+cleanup:
+	hook_list_clear(head, NULL);
+	free(head);
+	return ret;
+}
+
 static int run(int argc, const char **argv, const char *prefix,
 	       struct repository *repo UNUSED)
 {
@@ -77,6 +136,7 @@ int cmd_hook(int argc,
 	parse_opt_subcommand_fn *fn = NULL;
 	struct option builtin_hook_options[] = {
 		OPT_SUBCOMMAND("run", &fn, run),
+		OPT_SUBCOMMAND("list", &fn, list),
 		OPT_END(),
 	};
 
diff --git a/hook.c b/hook.c
index c008a7232d..979a97a538 100644
--- a/hook.c
+++ b/hook.c
@@ -61,7 +61,7 @@ static void hook_clear(struct hook *h, cb_data_free_fn cb_data_free)
 	free(h);
 }
 
-static void hook_list_clear(struct string_list *hooks, cb_data_free_fn cb_data_free)
+void hook_list_clear(struct string_list *hooks, cb_data_free_fn cb_data_free)
 {
 	struct string_list_item *item;
 
@@ -101,20 +101,7 @@ static void list_hooks_add_default(struct repository *r, const char *hookname,
 	string_list_append(hook_list, hook_path)->util = h;
 }
 
-/*
- * Provides a list of hook commands to run for the 'hookname' event.
- *
- * This function consolidates hooks from two sources:
- * 1. The config-based hooks (not yet implemented).
- * 2. The "traditional" hook found in the repository hooks directory
- *    (e.g., .git/hooks/pre-commit).
- *
- * The list is ordered by execution priority.
- *
- * The caller is responsible for freeing the memory of the returned list
- * using string_list_clear() and free().
- */
-static struct string_list *list_hooks(struct repository *r, const char *hookname,
+struct string_list *list_hooks(struct repository *r, const char *hookname,
 			       struct run_hooks_opt *options)
 {
 	struct string_list *hook_head;
diff --git a/hook.h b/hook.h
index 3256d2dddb..fea221f87d 100644
--- a/hook.h
+++ b/hook.h
@@ -163,7 +163,29 @@ struct hook_cb_data {
 	struct run_hooks_opt *options;
 };
 
-/*
+/**
+ * Provides a list of hook commands to run for the 'hookname' event.
+ *
+ * This function consolidates hooks from two sources:
+ * 1. The config-based hooks (not yet implemented).
+ * 2. The "traditional" hook found in the repository hooks directory
+ *    (e.g., .git/hooks/pre-commit).
+ *
+ * The list is ordered by execution priority.
+ *
+ * The caller is responsible for freeing the memory of the returned list
+ * using string_list_clear() and free().
+ */
+struct string_list *list_hooks(struct repository *r, const char *hookname,
+			       struct run_hooks_opt *options);
+
+/**
+ * Frees the memory allocated for the hook list, including the `struct hook`
+ * items and their internal state.
+ */
+void hook_list_clear(struct string_list *hooks, cb_data_free_fn cb_data_free);
+
+/**
  * Returns the path to the hook file, or NULL if the hook is missing
  * or disabled. Note that this points to static storage that will be
  * overwritten by further calls to find_hook and run_hook_*.
diff --git a/t/t1800-hook.sh b/t/t1800-hook.sh
index ed28a2fadb..3ec11f1249 100755
--- a/t/t1800-hook.sh
+++ b/t/t1800-hook.sh
@@ -10,9 +10,31 @@ test_expect_success 'git hook usage' '
 	test_expect_code 129 git hook run &&
 	test_expect_code 129 git hook run -h &&
 	test_expect_code 129 git hook run --unknown 2>err &&
+	test_expect_code 129 git hook list &&
+	test_expect_code 129 git hook list -h &&
 	grep "unknown option" err
 '
 
+test_expect_success 'git hook list: nonexistent hook' '
+	cat >stderr.expect <<-\EOF &&
+	warning: No hooks found for event '\''test-hook'\''
+	EOF
+	test_expect_code 1 git hook list test-hook 2>stderr.actual &&
+	test_cmp stderr.expect stderr.actual
+'
+
+test_expect_success 'git hook list: traditional hook from hookdir' '
+	test_hook test-hook <<-EOF &&
+	echo Test hook
+	EOF
+
+	cat >expect <<-\EOF &&
+	hook from hookdir
+	EOF
+	git hook list test-hook >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'git hook run: nonexistent hook' '
 	cat >stderr.expect <<-\EOF &&
 	error: cannot find a hook named test-hook

-- 
2.52.0.732.gb351b5166d.dirty