checkout: use --aggressive when running a 3-way merge (-m).
[gitweb.git] / diffcore-rename.c
index e17dd90058443ea75321f8c48818bd0094bd76a3..d57e8656cdcf1b999df30c01d3a8a042bc3ebb75 100644 (file)
@@ -4,8 +4,6 @@
 #include "cache.h"
 #include "diff.h"
 #include "diffcore.h"
-#include "delta.h"
-#include "count-delta.h"
 
 /* Table of rename/copy destinations */
 
@@ -56,12 +54,14 @@ static struct diff_rename_dst *locate_rename_dst(struct diff_filespec *two,
 /* Table of rename/copy src files */
 static struct diff_rename_src {
        struct diff_filespec *one;
+       unsigned short score; /* to remember the break score */
        unsigned src_path_left : 1;
 } *rename_src;
 static int rename_src_nr, rename_src_alloc;
 
 static struct diff_rename_src *register_rename_src(struct diff_filespec *one,
-                                                  int src_path_left)
+                                                  int src_path_left,
+                                                  unsigned short score)
 {
        int first, last;
 
@@ -91,6 +91,7 @@ static struct diff_rename_src *register_rename_src(struct diff_filespec *one,
                memmove(rename_src + first + 1, rename_src + first,
                        (rename_src_nr - first - 1) * sizeof(*rename_src));
        rename_src[first].one = one;
+       rename_src[first].score = score;
        rename_src[first].src_path_left = src_path_left;
        return &(rename_src[first]);
 }
@@ -135,8 +136,7 @@ static int estimate_similarity(struct diff_filespec *src,
         * match than anything else; the destination does not even
         * call into this function in that case.
         */
-       void *delta;
-       unsigned long delta_size, base_size, src_copied, literal_added;
+       unsigned long max_size, delta_size, base_size, src_copied, literal_added;
        unsigned long delta_limit;
        int score;
 
@@ -147,9 +147,9 @@ static int estimate_similarity(struct diff_filespec *src,
        if (!S_ISREG(src->mode) || !S_ISREG(dst->mode))
                return 0;
 
-       delta_size = ((src->size < dst->size) ?
-                     (dst->size - src->size) : (src->size - dst->size));
+       max_size = ((src->size > dst->size) ? src->size : dst->size);
        base_size = ((src->size < dst->size) ? src->size : dst->size);
+       delta_size = max_size - base_size;
 
        /* We would not consider edits that change the file size so
         * drastically.  delta_size must be smaller than
@@ -165,40 +165,22 @@ 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_limit);
-       if (!delta)
-               /* If delta_limit is exceeded, we have too much differences */
+       if (diffcore_count_changes(src->data, src->size,
+                                  dst->data, dst->size,
+                                  &src->cnt_data, &dst->cnt_data,
+                                  delta_limit,
+                                  &src_copied, &literal_added))
                return 0;
 
-       /* A delta that has a lot of literal additions would have
-        * big delta_size no matter what else it does.
+       /* How similar are they?
+        * what percentage of material in dst are from source?
         */
-       if (base_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE)
-               return 0;
-
-       /* Estimate the edit size by interpreting delta. */
-       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;
+       if (!dst->size)
+               score = 0; /* should not happen */
        else
-               delta_size = (src->size - src_copied) + literal_added;
-
-       /*
-        * Now we will give some score to it.  100% edit gets 0 points
-        * and 0% edit gets MAX_SCORE points.
-        */
-       score = MAX_SCORE - (MAX_SCORE * delta_size / base_size); 
-       if (score < 0) return 0;
-       if (MAX_SCORE < score) return MAX_SCORE;
+               score = src_copied * MAX_SCORE / max_size;
        return score;
 }
 
@@ -219,7 +201,10 @@ static void record_rename_pair(int dst_index, int src_index, int score)
        fill_filespec(two, dst->sha1, dst->mode);
 
        dp = diff_queue(NULL, one, two);
-       dp->score = score;
+       if (!strcmp(src->path, dst->path))
+               dp->score = rename_src[src_index].score;
+       else
+               dp->score = score;
        dp->source_stays = rename_src[src_index].src_path_left;
        rename_dst[dst_index].pair = dp;
 }
@@ -277,13 +262,13 @@ void diffcore_rename(struct diff_options *options)
                         * that means the source actually stays.
                         */
                        int stays = (p->broken_pair && !p->score);
-                       register_rename_src(p->one, stays);
+                       register_rename_src(p->one, stays, p->score);
                }
                else if (detect_rename == DIFF_DETECT_COPY)
-                       register_rename_src(p->one, 1);
+                       register_rename_src(p->one, 1, p->score);
        }
-       if (rename_dst_nr == 0 ||
-           (0 <= rename_limit && rename_limit < rename_dst_nr))
+       if (rename_dst_nr == 0 || rename_src_nr == 0 ||
+           (0 < rename_limit && rename_limit < rename_dst_nr))
                goto cleanup; /* nothing to do */
 
        /* We really want to cull the candidates list early
@@ -307,6 +292,9 @@ void diffcore_rename(struct diff_options *options)
        if (rename_count == rename_dst_nr)
                goto cleanup;
 
+       if (minimum_score == MAX_SCORE)
+               goto cleanup;
+
        num_create = (rename_dst_nr - rename_count);
        num_src = rename_src_nr;
        mx = xmalloc(sizeof(*mx) * num_create * num_src);
@@ -323,6 +311,8 @@ void diffcore_rename(struct diff_options *options)
                        m->score = estimate_similarity(one, two,
                                                       minimum_score);
                }
+               /* We do not need the text anymore */
+               diff_free_filespec_data(two);
                dst_cnt++;
        }
        /* cost matrix sorted by most to least similar pair */