help: use list_aliases() for alias listing

help.c has its own get_alias() config callback that duplicates the
parsing logic in alias.c. Consolidate by teaching list_aliases() to
also store the alias values (via the string_list util field), then
use it in list_all_cmds_help_aliases() instead of the private
callback.

This preserves the existing error checking for value-less alias
definitions by checking in alias.c rather than help.c.

No functional change intended.

Signed-off-by: Jonatan Holmgren <jonatan@jontes.page>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 19 insertions, 16 deletions

diff --git a/alias.c b/alias.c
index 1a1a141a0a..271acb9bf1 100644
--- a/alias.c
+++ b/alias.c
@@ -29,7 +29,13 @@ static int config_alias_cb(const char *key, const char *value,
 						 key, value);
 		}
 	} else if (data->list) {
-		string_list_append(data->list, p);
+		struct string_list_item *item;
+
+		if (!value)
+			return config_error_nonbool(key);
+
+		item = string_list_append(data->list, p);
+		item->util = xstrdup(value);
 	}
 
 	return 0;
diff --git a/help.c b/help.c
index 3c36d9c218..84b9e5efe4 100644
--- a/help.c
+++ b/help.c
@@ -20,6 +20,7 @@
 #include "prompt.h"
 #include "fsmonitor-ipc.h"
 #include "repository.h"
+#include "alias.h"
 
 #ifndef NO_CURL
 #include "git-curl-compat.h" /* For LIBCURL_VERSION only */
@@ -469,20 +470,6 @@ void list_developer_interfaces_help(void)
 	putchar('\n');
 }
 
-static int get_alias(const char *var, const char *value,
-		     const struct config_context *ctx UNUSED, void *data)
-{
-	struct string_list *list = data;
-
-	if (skip_prefix(var, "alias.", &var)) {
-		if (!value)
-			return config_error_nonbool(var);
-		string_list_append(list, var)->util = xstrdup(value);
-	}
-
-	return 0;
-}
-
 static void list_all_cmds_help_external_commands(void)
 {
 	struct string_list others = STRING_LIST_INIT_DUP;
@@ -502,7 +489,7 @@ static void list_all_cmds_help_aliases(int longest)
 	struct cmdname_help *aliases;
 	int i;
 
-	repo_config(the_repository, get_alias, &alias_list);
+	list_aliases(&alias_list);
 	string_list_sort(&alias_list);
 
 	for (i = 0; i < alias_list.nr; i++) {
diff --git a/t/t0014-alias.sh b/t/t0014-alias.sh
index 07a53e7366..a13d2be8ca 100755
--- a/t/t0014-alias.sh
+++ b/t/t0014-alias.sh
@@ -112,4 +112,14 @@ test_expect_success 'cannot alias-shadow a sample of regular builtins' '
 	done
 '
 
+test_expect_success 'alias without value reports error' '
+	test_when_finished "git config --unset alias.noval" &&
+	cat >>.git/config <<-\EOF &&
+	[alias]
+		noval
+	EOF
+	test_must_fail git noval 2>error &&
+	test_grep "alias.noval" error
+'
+
 test_done