git: treat "git -C '<path>'" as a no-op when <path> is emptykn/git-cd-to-empty

'git -C ""' unhelpfully dies with error "Cannot change to ''",
whereas the shell treats `cd ""' as a no-op.  Taking the shell's
behavior as a precedent, teach git to treat `-C ""' as a no-op, as
well.

Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/git.c b/git.c
index 6b5ae6a2ac..fdea110407 100644
--- a/git.c
+++ b/git.c
@@ -204,10 +204,12 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 				fprintf(stderr, "No directory given for -C.\n" );
 				usage(git_usage_string);
 			}
-			if (chdir((*argv)[1]))
-				die_errno("Cannot change to '%s'", (*argv)[1]);
-			if (envchanged)
-				*envchanged = 1;
+			if ((*argv)[1][0]) {
+				if (chdir((*argv)[1]))
+					die_errno("Cannot change to '%s'", (*argv)[1]);
+				if (envchanged)
+					*envchanged = 1;
+			}
 			(*argv)++;
 			(*argc)--;
 		} else {