Fix a pathological case in git detecting proper renames

diff --git a/diffcore-rename.c b/diffcore-rename.c
index f9ebea56406090af207f79951618742dcd7d397f..f64294e3cf45ad8f49b2a0ac613e2386c297af8b 100644 (file)
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -244,28 +244,35 @@ static int find_identical_files(struct file_similarity *src,
         * Walk over all the destinations ...
         */
        do {
-               struct diff_filespec *one = dst->filespec;
+               struct diff_filespec *target = dst->filespec;
                struct file_similarity *p, *best;
-               int i = 100;
+               int i = 100, best_score = -1;
 
                /*
                 * .. to find the best source match
                 */
                best = NULL;
                for (p = src; p; p = p->next) {
-                       struct diff_filespec *two = p->filespec;
+                       int score;
+                       struct diff_filespec *source = p->filespec;
 
                        /* False hash collission? */
-                       if (hashcmp(one->sha1, two->sha1))
+                       if (hashcmp(source->sha1, target->sha1))
                                continue;
                        /* Non-regular files? If so, the modes must match! */
-                       if (!S_ISREG(one->mode) || !S_ISREG(two->mode)) {
-                               if (one->mode != two->mode)
+                       if (!S_ISREG(source->mode) || !S_ISREG(target->mode)) {
+                               if (source->mode != target->mode)
                                        continue;
                        }
-                       best = p;
-                       if (basename_same(one, two))
-                               break;
+                       /* Give higher scores to sources that haven't been used already */
+                       score = !source->rename_used;
+                       score += basename_same(source, target);
+                       if (score > best_score) {
+                               best = p;
+                               best_score = score;
+                               if (score == 2)
+                                       break;
+                       }
 
                        /* Too many identical alternatives? Pick one */
                        if (!--i)