rev-parse: --abbrev option.

The new option behaves just like --verify, but outputs an
abbreviated object name that is unique within the repository.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/rev-parse.c b/rev-parse.c
index 7abad35..42969a6 100644 (file)
--- a/rev-parse.c
+++ b/rev-parse.c
@@ -20,6 +20,7 @@ static char *def = NULL;
 #define REVERSED 1
 static int show_type = NORMAL;
 static int symbolic = 0;
+static int abbrev = 0;
 static int output_sq = 0;
 
 static int revs_count = 0;
@@ -95,6 +96,8 @@ static void show_rev(int type, const unsigned char *sha1, const char *name)
                putchar('^');
        if (symbolic && name)
                show(name);
+       else if (abbrev)
+               show(find_unique_abbrev(sha1, abbrev));
        else
                show(sha1_to_hex(sha1));
 }
@@ -196,6 +199,17 @@ int main(int argc, char **argv)
                                verify = 1;
                                continue;
                        }
+                       if (!strcmp(arg, "--abbrev") ||
+                           !strncmp(arg, "--abbrev=", 9)) {
+                               filter &= ~(DO_FLAGS|DO_NOREV);
+                               verify = 1;
+                               abbrev = DEFAULT_ABBREV;
+                               if (arg[8] == '=')
+                                       abbrev = strtoul(arg + 9, NULL, 10);
+                               if (abbrev < 0 || 40 <= abbrev)
+                                       abbrev = DEFAULT_ABBREV;
+                               continue;
+                       }
                        if (!strcmp(arg, "--sq")) {
                                output_sq = 1;
                                continue;