Subject: [PATCH 1/3] ls-tree.c: support `--oid-only` option for "git-ls-tree"

From: Teng Long <[email-masked]>
Date: Mon, 15 Nov 2021 19:51:51 +0800

This commit supply an option names `--oid-only` to let `git ls-tree`
only print out the OID of the object. `--oid-only` and `--name-only`
are mutually exclusive in use.

Signed-off-by: Teng Long <[email-masked]>
---
 builtin/ls-tree.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/builtin/ls-tree.c b/builtin/ls-tree.c
index 3a442631c7..1f82229649 100644
--- a/builtin/ls-tree.c
+++ b/builtin/ls-tree.c
@@ -20,6 +20,7 @@ static int line_termination = '\n';
 #define LS_SHOW_TREES 4
 #define LS_NAME_ONLY 8
 #define LS_SHOW_SIZE 16
+#define LS_OID_ONLY 32
 static int abbrev;
 static int ls_options;
 static struct pathspec pathspec;
@@ -90,6 +91,14 @@ static int show_tree(const struct object_id *oid, struct strbuf *base,
 	else if (ls_options & LS_TREE_ONLY)
 		return 0;
 
+	if ((ls_options & LS_NAME_ONLY) && (ls_options & LS_OID_ONLY))
+		die(_("cannot specify --oid-only and --name-only at the same time"));
+
+	if (ls_options & LS_OID_ONLY) {
+		printf("%s\n", find_unique_abbrev(oid, abbrev));
+		return 0;
+	}
+
 	if (!(ls_options & LS_NAME_ONLY)) {
 		if (ls_options & LS_SHOW_SIZE) {
 			char size_text[24];
@@ -139,6 +148,8 @@ int cmd_ls_tree(int argc, const char **argv, const char *prefix)
 			LS_NAME_ONLY),
 		OPT_BIT(0, "name-status", &ls_options, N_("list only filenames"),
 			LS_NAME_ONLY),
+		OPT_BIT(0, "oid-only", &ls_options, N_("list only oids"),
+			LS_OID_ONLY),
 		OPT_SET_INT(0, "full-name", &chomp_prefix,
 			    N_("use full path names"), 0),
 		OPT_BOOL(0, "full-tree", &full_tree,
-- 
2.33.1.9.g5fbd2fc599.dirty