Make "git clone" a lot more user-friendly
[gitweb.git] / diffcore-rename.c
index 6ed8cf5aec7dc60d1eeeaed3a6a8781832aa3205..6a52699f732c76540d71ce1500bd8d838ee8a265 100644 (file)
@@ -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'))
-               return -1; /* that is not a -M nor -C 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;
@@ -249,7 +243,7 @@ void diffcore_rename(int detect_rename, int minimum_score)
        int num_create, num_src, dst_cnt;
 
        if (!minimum_score)
-               minimum_score = DEFAULT_MINIMUM_SCORE;
+               minimum_score = DEFAULT_RENAME_SCORE;
        renq.queue = NULL;
        renq.nr = renq.alloc = 0;
 
@@ -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);
        }
@@ -353,17 +353,36 @@ void diffcore_rename(int detect_rename, int minimum_score)
                        /*
                         * Deletion
                         *
-                        * We would output this delete record if renq
-                        * does not have a rename/copy to move
-                        * p->one->path out.
+                        * We would output this delete record if:
+                        *
+                        * (1) this is a broken delete and the counterpart
+                        *     broken create remains in the output; or
+                        * (2) this is not a broken delete, and renq does
+                        *     not have a rename/copy to move p->one->path
+                        *     out.
+                        *
+                        * Otherwise, the counterpart broken create
+                        * has been turned into a rename-edit; or
+                        * delete did not have a matching create to
+                        * begin with.
                         */
-                       for (j = 0; j < renq.nr; j++)
-                               if (!strcmp(renq.queue[j]->one->path,
-                                           p->one->path))
-                                       break;
-                       if (j < renq.nr)
-                               /* this path remains */
-                               pair_to_free = p;
+                       if (DIFF_PAIR_BROKEN(p)) {
+                               /* broken delete */
+                               struct diff_rename_dst *dst =
+                                       locate_rename_dst(p->one, 0);
+                               if (dst && dst->pair)
+                                       /* counterpart is now rename/copy */
+                                       pair_to_free = p;
+                       }
+                       else {
+                               for (j = 0; j < renq.nr; j++)
+                                       if (!strcmp(renq.queue[j]->one->path,
+                                                   p->one->path))
+                                               break;
+                               if (j < renq.nr)
+                                       /* this path remains */
+                                       pair_to_free = p;
+                       }
 
                        if (pair_to_free)
                                ;