convert "oidcmp() == 0" to oideq()

Using the more restrictive oideq() should, in the long run,
give the compiler more opportunities to optimize these
callsites. For now, this conversion should be a complete
noop with respect to the generated code.

The result is also perhaps a little more readable, as it
avoids the "zero is equal" idiom. Since it's so prevalent in
C, I think seasoned programmers tend not to even notice it
anymore, but it can sometimes make for awkward double
negations (e.g., we can drop a few !!oidcmp() instances
here).

This patch was generated almost entirely by the included
coccinelle patch. This mechanical conversion should be
completely safe, because we check explicitly for cases where
oidcmp() is compared to 0, which is what oideq() is doing
under the hood. Note that we don't have to catch "!oidcmp()"
separately; coccinelle's standard isomorphisms make sure the
two are treated equivalently.

I say "almost" because I did hand-edit the coccinelle output
to fix up a few style violations (it mostly keeps the
original formatting, but sometimes unwraps long lines).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/builtin/replace.c b/builtin/replace.c
index 4f05791f3e..8e67e09819 100644
--- a/builtin/replace.c
+++ b/builtin/replace.c
@@ -343,7 +343,7 @@ static int edit_and_replace(const char *object_ref, int force, int raw)
 	}
 	free(tmpfile);
 
-	if (!oidcmp(&old_oid, &new_oid))
+	if (oideq(&old_oid, &new_oid))
 		return error(_("new object is the same as the old one: '%s'"), oid_to_hex(&old_oid));
 
 	return replace_object_oid(object_ref, &old_oid, "replacement", &new_oid, force);
@@ -414,7 +414,7 @@ static int check_one_mergetag(struct commit *commit,
 		if (get_oid(mergetag_data->argv[i], &oid) < 0)
 			return error(_("not a valid object name: '%s'"),
 				     mergetag_data->argv[i]);
-		if (!oidcmp(&tag->tagged->oid, &oid))
+		if (oideq(&tag->tagged->oid, &oid))
 			return 0; /* found */
 	}
 
@@ -474,7 +474,7 @@ static int create_graft(int argc, const char **argv, int force, int gentle)
 
 	strbuf_release(&buf);
 
-	if (!oidcmp(&old_oid, &new_oid)) {
+	if (oideq(&old_oid, &new_oid)) {
 		if (gentle) {
 			warning(_("graft for '%s' unnecessary"), oid_to_hex(&old_oid));
 			return 0;