show-branch: usability updates.

This does three things:

 . It simplifies the logic to handle the case in which no
   refs are given on the command line, and fixes the bug
   when only "--heads" is specified.  Earlier we showed
   them twice.

 . It avoids to add the same ref twice.

 . It sorts the glob result (e.g. "git show-branch
   'tags/v1.0*'") according to a more version friendly
   sort order.

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

diff --git a/show-branch.c b/show-branch.c
index 3fe62b7..15b1968 100644 (file)
--- a/show-branch.c
+++ b/show-branch.c
@@ -284,10 +284,54 @@ static void show_one_commit(struct commit *commit, int no_name)
 static char *ref_name[MAX_REVS + 1];
 static int ref_name_cnt;
 
+static const char *find_digit_prefix(const char *s, int *v)
+{
+       const char *p;
+       int ver;
+       char ch;
+
+       for (p = s, ver = 0;
+            '0' <= (ch = *p) && ch <= '9';
+            p++)
+               ver = ver * 10 + ch - '0';
+       *v = ver;
+       return p;
+}
+
+
+static int version_cmp(const char *a, const char *b)
+{
+       while (1) {
+               int va, vb;
+
+               a = find_digit_prefix(a, &va);
+               b = find_digit_prefix(b, &vb);
+               if (va != vb)
+                       return va - vb;
+
+               while (1) {
+                       int ca = *a;
+                       int cb = *b;
+                       if ('0' <= ca && ca <= '9')
+                               ca = 0;
+                       if ('0' <= cb && cb <= '9')
+                               cb = 0;
+                       if (ca != cb)
+                               return ca - cb;
+                       if (!ca)
+                               break;
+                       a++;
+                       b++;
+               }
+               if (!*a && !*b)
+                       return 0;
+       }
+}
+
 static int compare_ref_name(const void *a_, const void *b_)
 {
        const char * const*a = a_, * const*b = b_;
-       return strcmp(*a, *b);
+       return version_cmp(*a, *b);
 }
 
 static void sort_ref_range(int bottom, int top)
@@ -299,8 +343,15 @@ static void sort_ref_range(int bottom, int top)
 static int append_ref(const char *refname, const unsigned char *sha1)
 {
        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+       int i;
+
        if (!commit)
                return 0;
+       /* Avoid adding the same thing twice */
+       for (i = 0; i < ref_name_cnt; i++)
+               if (!strcmp(refname, ref_name[i]))
+                       return 0;
+
        if (MAX_REVS <= ref_name_cnt) {
                fprintf(stderr, "warning: ignoring %s; "
                        "cannot handle more than %d refs\n",
@@ -512,19 +563,17 @@ int main(int ac, char **av)
        if (1 < independent + merge_base + (extra != 0))
                usage(show_branch_usage);
 
+       /* If nothing is specified, show all branches by default */
+       if (ac + all_heads + all_tags == 0)
+               all_heads = 1;
+
        if (all_heads + all_tags)
                snarf_refs(all_heads, all_tags);
-
-       if (ac) {
-               while (0 < ac) {
-                       append_one_rev(*av);
-                       ac--; av++;
-               }
-       }
-       else {
-               /* If no revs given, then add heads */
-               snarf_refs(1, 0);
+       while (0 < ac) {
+               append_one_rev(*av);
+               ac--; av++;
        }
+
        if (!ref_name_cnt) {
                fprintf(stderr, "No revs to be shown.\n");
                exit(0);