diffcore-rename: avoid usage of global in too_many_rename_candidates()

too_many_rename_candidates() got the number of rename destinations via
an argument to the function, but the number of rename sources via a
global variable.  That felt rather inconsistent.  Pass in the number of
rename sources as an argument as well.

While we are at it... We had a local variable, num_src, that served two
purposes.  Initially it was set to the global value, but later was used
for counting a subset of the number of sources.  Since we now have a
function argument for the former usage, introduce a clearer variable
name for the latter usage.

This patch has no behavioral changes; it's just renaming and passing an
argument instead of grabbing it from the global namespace.  (You may
find it easier to view the patch using git diff's --color-words option.)

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diffcore-rename.c

@@ -434,12 +434,11 @@ static void record_if_better(struct diff_score m[], struct diff_score *o)
  * 1 if we need to disable inexact rename detection;
  * 2 if we would be under the limit if we were given -C instead of -C -C.
  */
-static int too_many_rename_candidates(int num_destinations,
+static int too_many_rename_candidates(int num_destinations, int num_sources,
 				      struct diff_options *options)
 {
 	int rename_limit = options->rename_limit;
-	int num_src = rename_src_nr;
+	int i, limited_sources;
-	int i;
 
 	options->needed_rename_limit = 0;
 
@@ -447,30 +446,30 @@ static int too_many_rename_candidates(int num_destinations,
 	 * This basically does a test for the rename matrix not
 	 * growing larger than a "rename_limit" square matrix, ie:
 	 *
-	 *    num_destinations * num_src > rename_limit * rename_limit
+	 *    num_destinations * num_sources > rename_limit * rename_limit
 	 */
 	if (rename_limit <= 0)
 		rename_limit = 32767;
-	if ((num_destinations <= rename_limit || num_src <= rename_limit) &&
+	if ((num_destinations <= rename_limit || num_sources <= rename_limit) &&
-	    ((uint64_t)num_destinations * (uint64_t)num_src
+	    ((uint64_t)num_destinations * (uint64_t)num_sources
 	     <= (uint64_t)rename_limit * (uint64_t)rename_limit))
 		return 0;
 
 	options->needed_rename_limit =
-		num_src > num_destinations ? num_src : num_destinations;
+		num_sources > num_destinations ? num_sources : num_destinations;
 
 	/* Are we running under -C -C? */
 	if (!options->flags.find_copies_harder)
 		return 1;
 
 	/* Would we bust the limit if we were running under -C? */
-	for (num_src = i = 0; i < rename_src_nr; i++) {
+	for (limited_sources = i = 0; i < num_sources; i++) {
 		if (diff_unmodified_pair(rename_src[i].p))
 			continue;
-		num_src++;
+		limited_sources++;
 	}
-	if ((num_destinations <= rename_limit || num_src <= rename_limit) &&
+	if ((num_destinations <= rename_limit || limited_sources <= rename_limit) &&
-	    ((uint64_t)num_destinations * (uint64_t)num_src
+	    ((uint64_t)num_destinations * (uint64_t)limited_sources
 	     <= (uint64_t)rename_limit * (uint64_t)rename_limit))
 		return 2;
 	return 1;
@@ -576,7 +575,8 @@ void diffcore_rename(struct diff_options *options)
 	if (!num_destinations)
 		goto cleanup;
 
-	switch (too_many_rename_candidates(num_destinations, options)) {
+	switch (too_many_rename_candidates(num_destinations, rename_src_nr,
+					   options)) {
 	case 1:
 		goto cleanup;
 	case 2: