X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=diffcore-break.c;h=ed0e14c6d8b1b8347f20c890854972be6c6a234c;hb=HEAD;hp=06f9a7f0ee25891ff6f4dd9646e39cd4c8b105fd;hpb=36d277c72d90d32f99616072b64a2652248f5264;p=git.git

diff --git a/diffcore-break.c b/diffcore-break.c
index 06f9a7f0..ed0e14c6 100644
--- a/diffcore-break.c
+++ b/diffcore-break.c
@@ -4,8 +4,6 @@
 #include "cache.h"
 #include "diff.h"
 #include "diffcore.h"
-#include "delta.h"
-#include "count-delta.h"
 
 static int should_break(struct diff_filespec *src,
 			struct diff_filespec *dst,
@@ -47,9 +45,8 @@ static int should_break(struct diff_filespec *src,
 	 * The value we return is 1 if we want the pair to be broken,
 	 * or 0 if we do not.
 	 */
-	void *delta;
-	unsigned long delta_size, base_size, src_copied, literal_added;
-	int to_break = 0;
+	unsigned long delta_size, base_size, src_copied, literal_added,
+		src_removed;
 
 	*merge_score_p = 0; /* assume no deletion --- "do not break"
 			     * is the default.
@@ -58,50 +55,58 @@ static int should_break(struct diff_filespec *src,
 	if (!S_ISREG(src->mode) || !S_ISREG(dst->mode))
 		return 0; /* leave symlink rename alone */
 
+	if (src->sha1_valid && dst->sha1_valid &&
+	    !memcmp(src->sha1, dst->sha1, 20))
+		return 0; /* they are the same */
+
 	if (diff_populate_filespec(src, 0) || diff_populate_filespec(dst, 0))
 		return 0; /* error but caught downstream */
 
 	base_size = ((src->size < dst->size) ? src->size : dst->size);
+	if (base_size < MINIMUM_BREAK_SIZE)
+		return 0; /* we do not break too small filepair */
 
-	delta = diff_delta(src->data, src->size,
-			   dst->data, dst->size,
-			   &delta_size, 0);
+	if (diffcore_count_changes(src->data, src->size,
+				   dst->data, dst->size,
+				   NULL, NULL,
+				   0,
+				   &src_copied, &literal_added))
+		return 0;
 
-	/* Estimate the edit size by interpreting delta. */
-	if (count_delta(delta, delta_size,
-			&src_copied, &literal_added)) {
-		free(delta);
-		return 0; /* we cannot tell */
+	/* sanity */
+	if (src->size < src_copied)
+		src_copied = src->size;
+	if (dst->size < literal_added + src_copied) {
+		if (src_copied < dst->size)
+			literal_added = dst->size - src_copied;
+		else
+			literal_added = 0;
 	}
-	free(delta);
+	src_removed = src->size - src_copied;
 
 	/* Compute merge-score, which is "how much is removed
 	 * from the source material".  The clean-up stage will
 	 * merge the surviving pair together if the score is
 	 * less than the minimum, after rename/copy runs.
 	 */
-	if (src->size <= src_copied)
-		; /* all copied, nothing removed */
-	else {
-		delta_size = src->size - src_copied;
-		*merge_score_p = delta_size * MAX_SCORE / src->size;
-	}
-	
+	*merge_score_p = src_removed * MAX_SCORE / src->size;
+
 	/* Extent of damage, which counts both inserts and
 	 * deletes.
 	 */
-	if (src->size + literal_added <= src_copied)
-		delta_size = 0; /* avoid wrapping around */
-	else
-		delta_size = (src->size - src_copied) + literal_added;
-	
-	/* We break if the edit exceeds the minimum.
-	 * i.e. (break_score / MAX_SCORE < delta_size / base_size)
+	delta_size = src_removed + literal_added;
+	if (delta_size * MAX_SCORE / base_size < break_score)
+		return 0;
+
+	/* If you removed a lot without adding new material, that is
+	 * not really a rewrite.
 	 */
-	if (break_score * base_size < delta_size * MAX_SCORE)
-		to_break = 1;
+	if ((src->size * break_score < src_removed * MAX_SCORE) &&
+	    (literal_added * 20 < src_removed) &&
+	    (literal_added * 20 < src_copied))
+		return 0;
 
-	return to_break;
+	return 1;
 }
 
 void diffcore_break(int break_score)
@@ -168,8 +173,7 @@ void diffcore_break(int break_score)
 		    !S_ISDIR(p->one->mode) && !S_ISDIR(p->two->mode) &&
 		    !strcmp(p->one->path, p->two->path)) {
 			if (should_break(p->one, p->two,
-					 break_score, &score) &&
-			    MINIMUM_BREAK_SIZE <= p->one->size) {
+					 break_score, &score)) {
 				/* Split this into delete and create */
 				struct diff_filespec *null_one, *null_two;
 				struct diff_filepair *dp;