Use a *real* built-in diff generator

diff --git a/show-branch.c b/show-branch.c
index 5a86ae2f9ed3159d082158c04bea51c39cb4477f..24efb65e622d8dfe44db22e5bc23c9f8cc328109 100644 (file)
--- a/show-branch.c
+++ b/show-branch.c
@@ -5,7 +5,7 @@
 #include "refs.h"
 
 static const char show_branch_usage[] =
-"git-show-branch [--current] [--all] [--heads] [--tags] [--topo-order] [--more=count | --list | --independent | --merge-base ] [<refs>...]";
+"git-show-branch [--current] [--all] [--heads] [--tags] [--topo-order] [--more=count | --list | --independent | --merge-base ] [--topics] [<refs>...]";
 
 static int default_num = 0;
 static int default_alloc = 0;
@@ -547,6 +547,7 @@ int main(int ac, char **av)
        int shown_merge_point = 0;
        int with_current_branch = 0;
        int head_at = -1;
+       int topics = 0;
 
        setup_git_directory();
        git_config(git_show_branch_config);
@@ -587,6 +588,8 @@ int main(int ac, char **av)
                        independent = 1;
                else if (!strcmp(arg, "--topo-order"))
                        lifo = 1;
+               else if (!strcmp(arg, "--topics"))
+                       topics = 1;
                else if (!strcmp(arg, "--date-order"))
                        lifo = 0;
                else
@@ -724,11 +727,17 @@ int main(int ac, char **av)
        while (seen) {
                struct commit *commit = pop_one_commit(&seen);
                int this_flag = commit->object.flags;
+               int is_merge_point = ((this_flag & all_revs) == all_revs);
 
-               shown_merge_point |= ((this_flag & all_revs) == all_revs);
+               shown_merge_point |= is_merge_point;
 
                if (1 < num_rev) {
                        int is_merge = !!(commit->parents && commit->parents->next);
+                       if (topics &&
+                           !is_merge_point &&
+                           (this_flag & (1u << REV_SHIFT)))
+                               continue;
+
                        for (i = 0; i < num_rev; i++) {
                                int mark;
                                if (!(this_flag & (1u << (i + REV_SHIFT))))