Clean up GIT_UNUSED macros on all platforms

It turns out that commit 31e9cfc4cbcaf1b38cdd3dbe3282a8f57e5366a5
did not fix the GIT_USUSED behavior on all platforms.  This commit
walks through and really cleans things up more thoroughly, getting
rid of the unnecessary stuff.

To remove the use of some GIT_UNUSED, I ended up adding a couple
of new iterators for hashtables that allow you to iterator just
over keys or just over values.

In making this change, I found a bug in the clar tests (where we
were doing *count++ but meant to do (*count)++ to increment the
value).  I fixed that but then found the test failing because it
was not really using an empty repo.  So, I took some of the code
that I wrote for iterator testing and moved it to clar_helpers.c,
then made use of that to make it easier to open fixtures on a
per test basis even within a single test file.

1 files changed, 4 insertions, 4 deletions

diff --git a/tests/t18-status.c b/tests/t18-status.c
index 8bccb7106..aeadd5e6d 100644
--- a/tests/t18-status.c
+++ b/tests/t18-status.c
@@ -156,14 +156,14 @@ BEGIN_TEST(statuscb0, "test retrieving status for worktree of repository")
 	git_futils_rmdir_r(TEMP_REPO_FOLDER, 1);
 END_TEST
 
-static int status_cb1(const char *GIT_UNUSED(path), unsigned int GIT_UNUSED(status_flags), void *payload)
+static int status_cb1(const char *path, unsigned int status_flags, void *payload)
 {
 	int *count = (int *)payload;;
 
-	GIT_UNUSED_ARG(path);
-	GIT_UNUSED_ARG(status_flags);
+	GIT_UNUSED(path);
+	GIT_UNUSED(status_flags);
 
-	(void) *count++;
+	(*count)++;
 
 	return GIT_SUCCESS;
 }