[PATCH] Show binary file size change in diff --stat

[Andy Parkins <andyparkins@gmail.com>]

Previously, a binary file in the diffstat would show as:

 some-binary-file.bin       |  Bin

The space after the "Bin" was never used.  This patch changes binary
lines in the diffstat to be:

 some-binary-file.bin       |  Bin +123456B -12345B

The "+" item is the size of the new version, the "-" item is the size of
the old version.  If a size is 0 it's not shown (although it would
probably be better to treat no-file differently from zero-byte-file).

The "B" (for bytes) is shown to highlight the fact that these numbers
are not "number of lines", but actual bytes.

The user can see what changed in the binary file, and how big the new
file is.  This is in keeping with the information in the rest of the
diffstat.

The diffstat_t members "added" and "deleted" were unused when the file
was binary, so this patch loads them with the file sizes in
builtin_diffstat().  These figures are then read in show_stats() when
the file is marked binary.

Signed-off-by: Andy Parkins <andyparkins@gmail.com>
---
 diff.c |   15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/diff.c b/diff.c
index d1eae72..174b84e 100644
--- a/diff.c
+++ b/diff.c
@@ -808,7 +808,14 @@ static void show_stats(struct diffstat_t* data, struct diff_options *options)
 
 		if (data->files[i]->is_binary) {
 			show_name(prefix, name, len, reset, set);
-			printf("  Bin\n");
+			printf("  Bin ");
+			if (added != 0)
+				printf("%s+%iB%s", add_c, added, reset);
+			if (added != 0 && deleted != 0 )
+				printf(" ");
+			if (deleted != 0)
+				printf("%s-%iB%s", del_c, deleted, reset);
+			printf("\n");
 			goto free_diffstat_file;
 		}
 		else if (data->files[i]->is_unmerged) {
@@ -1179,9 +1186,11 @@ static void builtin_diffstat(const char *name_a, const char *name_b,
 	if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 		die("unable to read files to diff");
 
-	if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
+	if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2)) {
 		data->is_binary = 1;
-	else {
+		data->added = mf2.size;
+		data->deleted = mf1.size;
+	} else {
 		/* Crazy xdl interfaces.. */
 		xpparam_t xpp;
 		xdemitconf_t xecfg;
-- 
1.5.0.2.778.gdcb06