[PATCH] rev-parse --show-prefix: add in trailing newline

Print out a trailing newline when --show-prefix is run with cwd
at the top level of the tree which results in an empty prefix.
Behavior is now like --show-cdup.

Fixes an expected failure in t1501.

Signed-off-by: Ross Lagerwall <redacted>
---
 builtin/rev-parse.c |    2 ++
 t/t1501-worktree.sh |    2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index 98d1cbe..733f626 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c

@@ -634,6 +634,8 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 			if (!strcmp(arg, "--show-prefix")) {
 				if (prefix)
 					puts(prefix);
+				else
+					putchar('\n');
 				continue;
 			}
 			if (!strcmp(arg, "--show-cdup")) {

diff --git a/t/t1501-worktree.sh b/t/t1501-worktree.sh
index e661147..8f36aa9 100755
--- a/t/t1501-worktree.sh
+++ b/t/t1501-worktree.sh

@@ -68,7 +68,7 @@ test_expect_success 'inside work tree' '
 	)
 '
 
-test_expect_failure 'empty prefix is actually written out' '
+test_expect_success 'empty prefix is actually written out' '
 	echo >expected &&
 	(
 		cd work &&

-- 
1.7.10

(cc-ing Duy)
Hi,

Ross Lagerwall wrote:

This makes the output more consistent but it is a little puzzling how
it does that.  Why is prefix NULL instead of "" when we are at the
toplevel of the worktree?

Thanks,
Jonathan

2012/4/11 Jonathan Nieder [off-list ref]:

(cc-ing Duy)
Hi,

Ross Lagerwall wrote:

quoted

--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c

@@ -634,6 +634,8 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)

                      if (!strcmp(arg, "--show-prefix")) {
                              if (prefix)
                                      puts(prefix);
+                             else
+                                     putchar('\n');
                              continue;

This makes the output more consistent but it is a little puzzling how
it does that.  Why is prefix NULL instead of "" when we are at the
toplevel of the worktree?

It dates back to the first version of setup_git_directory() in d288a70
([PATCH] Make "git diff" work inside relative subdirectories -
2005-08-16). If we get "", setup_git_.. converts it to NULL. Although
I think Linus made a mistake in the first version of "rev-parse
--git-dir" doing "puts(prefix);" unconditionally in the same commit.
Junio fixed --git-dir in 4866ccf (Rationalize output selection in
rev-parse. - 2005-08-24) with the "if (prefix)" clause and should have
added the "else putchar('\n');" there too, I think.
-- 
Duy