Fix '--dirstat' with cross-directory renaming

The dirstat code depends on the fact that we always generate diffs with the names sorted, since it then just does a single-pass walk-over of the sorted list of names and how many changes there were. The sorting means that all files are nicely grouped by directory. That all works fine. Except when we have rename detection, and suddenly the nicely sorted list of pathnames isn't all that sorted at all. And now the single-pass dirstat walk gets all confused, and you can get results like this: [torvalds@nehalem linux]$ git diff --dirstat=2 -M v2.6.27-rc4..v2.6.27-rc5 3.0% arch/powerpc/configs/ 6.8% arch/arm/configs/ 2.7% arch/powerpc/configs/ 4.2% arch/arm/configs/ 5.6% arch/powerpc/configs/ 8.4% arch/arm/configs/ 5.5% arch/powerpc/configs/ 23.3% arch/arm/configs/ 8.6% arch/powerpc/configs/ 4.0% arch/ 4.4% drivers/usb/musb/ 4.0% drivers/watchdog/ 7.6% drivers/ 3.5% fs/ The trivial fix is to add a sorting pass, fixing it to: [torvalds@nehalem linux]$ git diff --dirstat=2 -M v2.6.27-rc4..v2.6.27-rc5 43.0% arch/arm/configs/ 25.5% arch/powerpc/configs/ 5.3% arch/ 4.4% drivers/usb/musb/ 4.0% drivers/watchdog/ 7.6% drivers/ 3.5% fs/ Spot the difference. In case anybody wonders: it's because of a ton of renames from {include/asm-blackfin => arch/blackfin/include/asm} that just totally messed up the file ordering in between arch/arm and arch/powerpc. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Linus Torvalds committed Aug 28, 2008 at 16:19 UTC 441bca0bbc6d80a78ce332ef4fa6225155dfbce6

1 file changed +8

diff.c

@@ -1054,6 +1054,13 @@ static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long ch

1054 return this_dir;

1055 }

1056

1057 +static int dirstat_compare(const void *_a, const void *_b)

1058 +{

1059 + const struct dirstat_file *a = _a;

1060 + const struct dirstat_file *b = _b;

1061 + return strcmp(a->name, b->name);

1062 +}

1063 +

1064 static void show_dirstat(struct diff_options *options)

1065 {

1066 int i;

@@ -1113,6 +1120,7 @@ static void show_dirstat(struct diff_options *options)

1120 return;

1121

1122 /* Show all directories with more than x% of the changes */

1123 + qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);

1124 gather_dirstat(options->file, &dir, changed, "", 0);

1125 }

1126