path: root/diff-cache.c
diff options
authorJunio C Hamano <>2005-05-30 07:08:37 (GMT)
committerLinus Torvalds <>2005-05-30 17:35:49 (GMT)
commitf345b0a066572206aac4a4f9a57d746e213b6bff (patch)
tree60d5548ce7ca6e62b8b934cc016c01ddb373c3fb /diff-cache.c
parent2cd68882ee8629f9782be017007fff4c78e45e45 (diff)
[PATCH] Add -B flag to diff-* brothers.
A new diffcore transformation, diffcore-break.c, is introduced. When the -B flag is given, a patch that represents a complete rewrite is broken into a deletion followed by a creation. This makes it easier to review such a complete rewrite patch. The -B flag takes the same syntax as the -M and -C flags to specify the minimum amount of non-source material the resulting file needs to have to be considered a complete rewrite, and defaults to 99% if not specified. As the new test demonstrates, if a file is a complete rewrite, it is broken into a delete/create pair, which can further be subjected to the usual rename detection if -M or -C is used. For example, if file0 gets completely rewritten to make it as if it were rather based on file1 which itself disappeared, the following happens: The original change looks like this: file0 --> file0' (quite different from file0) file1 --> /dev/null After diffcore-break runs, it would become this: file0 --> /dev/null /dev/null --> file0' file1 --> /dev/null Then diffcore-rename matches them up: file1 --> file0' The internal score values are finer grained now. Earlier maximum of 10000 has been raised to 60000; there is no user visible changes but there is no reason to waste available bits. Signed-off-by: Junio C Hamano <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'diff-cache.c')
1 files changed, 9 insertions, 2 deletions
diff --git a/diff-cache.c b/diff-cache.c
index c097826..7d067a8 100644
--- a/diff-cache.c
+++ b/diff-cache.c
@@ -9,6 +9,7 @@ static int diff_setup_opt = 0;
static int diff_score_opt = 0;
static const char *pickaxe = NULL;
static int pickaxe_opts = 0;
+static int diff_break_opt = -1;
/* A file entry went away or appeared */
static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
@@ -188,6 +189,10 @@ int main(int argc, const char **argv)
diff_output_format = DIFF_FORMAT_PATCH;
+ if (!strncmp(arg, "-B", 2)) {
+ diff_break_opt = diff_scoreopt_parse(arg);
+ continue;
+ }
if (!strncmp(arg, "-M", 2)) {
detect_rename = DIFF_DETECT_RENAME;
diff_score_opt = diff_scoreopt_parse(arg);
@@ -240,9 +245,11 @@ int main(int argc, const char **argv)
die("unable to read tree object %s", tree_name);
ret = diff_cache(active_cache, active_nr);
- diffcore_std(pathspec,
+ diffcore_std(pathspec ? : NULL,
detect_rename, diff_score_opt,
- pickaxe, pickaxe_opts);
+ pickaxe, pickaxe_opts,
+ diff_break_opt);
diff_flush(diff_output_format, 1);
return ret;