Make "git checkout" create new branches on demand

diff --git a/diffcore-rename.c b/diffcore-rename.c
index 8ed37dafda92048ffe67a485981d329726e6f41c..6a52699f732c76540d71ce1500bd8d838ee8a265 100644 (file)
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -135,7 +135,8 @@ static int estimate_similarity(struct diff_filespec *src,
         * call into this function in that case.
         */
        void *delta;
-       unsigned long delta_size, base_size;
+       unsigned long delta_size, base_size, src_copied, literal_added;
+       unsigned long delta_limit;
        int score;
 
        /* We deal only with regular files.  Symlink renames are handled
@@ -163,9 +164,13 @@ static int estimate_similarity(struct diff_filespec *src,
        if (diff_populate_filespec(src, 0) || diff_populate_filespec(dst, 0))
                return 0; /* error but caught downstream */
 
+       delta_limit = base_size * (MAX_SCORE-minimum_score) / MAX_SCORE;
        delta = diff_delta(src->data, src->size,
                           dst->data, dst->size,
-                          &delta_size);
+                          &delta_size, delta_limit);
+       if (!delta)
+               /* If delta_limit is exceeded, we have too much differences */
+               return 0;
 
        /* A delta that has a lot of literal additions would have
         * big delta_size no matter what else it does.
@@ -174,10 +179,17 @@ static int estimate_similarity(struct diff_filespec *src,
                return 0;
 
        /* Estimate the edit size by interpreting delta. */
-       delta_size = count_delta(delta, delta_size);
-       free(delta);
-       if (delta_size == UINT_MAX)
+       if (count_delta(delta, delta_size, &src_copied, &literal_added)) {
+               free(delta);
                return 0;
+       }
+       free(delta);
+
+       /* Extent of damage */
+       if (src->size + literal_added < src_copied)
+               delta_size = 0;
+       else
+               delta_size = (src->size - src_copied) + literal_added;
 
        /*
         * Now we will give some score to it.  100% edit gets 0 points
@@ -222,24 +234,6 @@ static int score_compare(const void *a_, const void *b_)
        return b->score - a->score;
 }
 
-int diff_scoreopt_parse(const char *opt)
-{
-       int diglen, num, scale, i;
-       if (opt[0] != '-' || (opt[1] != 'M' && opt[1] != 'C' && opt[1] != 'B'))
-               return -1; /* that is not a -M, -C nor -B option */
-       diglen = strspn(opt+2, "0123456789");
-       if (diglen == 0 || strlen(opt+2) != diglen)
-               return 0; /* use default */
-       sscanf(opt+2, "%d", &num);
-       for (i = 0, scale = 1; i < diglen; i++)
-               scale *= 10;
-
-       /* user says num divided by scale and we say internally that
-        * is MAX_SCORE * num / scale.
-        */
-       return MAX_SCORE * num / scale;
-}
-
 void diffcore_rename(int detect_rename, int minimum_score)
 {
        struct diff_queue_struct *q = &diff_queued_diff;
@@ -260,8 +254,14 @@ void diffcore_rename(int detect_rename, int minimum_score)
                                continue; /* unmerged */
                        else
                                locate_rename_dst(p->two, 1);
-               else if (!DIFF_FILE_VALID(p->two))
-                       register_rename_src(p->one, 0);
+               else if (!DIFF_FILE_VALID(p->two)) {
+                       /* If the source is a broken "delete", and
+                        * they did not really want to get broken,
+                        * that means the source actually stays.
+                        */
+                       int stays = (p->broken_pair && !p->score);
+                       register_rename_src(p->one, stays);
+               }
                else if (detect_rename == DIFF_DETECT_COPY)
                        register_rename_src(p->one, 1);
        }