[PATCH v2 1/2] grep: only add delimiter if there isn't one already

[Stefan Hajnoczi <stefanha@redhat.com>]

git-grep(1) output does not follow git's own syntax:

  $ git grep malloc v2.9.3:t/
  v2.9.3:t/:test-lib.sh:  setup_malloc_check () {
  $ git show v2.9.3:t/:test-lib.sh
  fatal: Path 't/:test-lib.sh' does not exist in 'v2.9.3'

This patch avoids emitting the unnecessary ':' delimiter if the name
already ends with ':' or '/':

  $ git grep malloc v2.9.3:
  v2.9.3:t/test-lib.sh:   setup_malloc_check () {
  $ git show v2.9.3:t/test-lib.sh
  (succeeds)

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 builtin/grep.c  |  6 +++++-
 t/t7810-grep.sh | 21 +++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/builtin/grep.c b/builtin/grep.c
index 8887b6a..90a4f3d 100644
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -491,7 +491,11 @@ static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 		strbuf_init(&base, PATH_MAX + len + 1);
 		if (len) {
 			strbuf_add(&base, name, len);
-			strbuf_addch(&base, ':');
+
+			/* Add a delimiter if there isn't one already */
+			if (name[len - 1] != '/' && name[len - 1] != ':') {
+				strbuf_addch(&base, ':');
+			}
 		}
 		init_tree_desc(&tree, data, size);
 		hit = grep_tree(opt, pathspec, &tree, &base, base.len,
diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh
index de2405c..e804a3f 100755
--- a/t/t7810-grep.sh
+++ b/t/t7810-grep.sh
@@ -1435,4 +1435,25 @@ test_expect_success 'grep does not report i-t-a and assume unchanged with -L' '
 	test_cmp expected actual
 '
 
+cat >expected <<EOF
+HEAD:t/a/v:vvv
+HEAD:t/v:vvv
+EOF
+
+test_expect_success 'grep outputs valid <rev>:<path> for HEAD:t/' '
+	git grep vvv HEAD:t/ >actual &&
+	test_cmp expected actual
+'
+
+cat >expected <<EOF
+HEAD:t/a/v:vvv
+HEAD:t/v:vvv
+HEAD:v:vvv
+EOF
+
+test_expect_success 'grep outputs valid <rev>:<path> for HEAD:' '
+	git grep vvv HEAD: >actual &&
+	test_cmp expected actual
+'
+
 test_done
-- 
2.9.3