Merge branch 'jn/userdiff-perl-updates'

diff --git a/builtin/merge.c b/builtin/merge.c
index 9661c8f425b82866552d435413928c60d59cb9ad..5a2a1eb797c88990337f0b9cbb5dcabc73222a22 100644 (file)
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -550,6 +550,15 @@ static int git_merge_config(const char *k, const char *v, void *cb)
                if (is_bool && shortlog_len)
                        shortlog_len = DEFAULT_MERGE_LOG_LEN;
                return 0;
+       } else if (!strcmp(k, "merge.ff")) {
+               int boolval = git_config_maybe_bool(k, v);
+               if (0 <= boolval) {
+                       allow_fast_forward = boolval;
+               } else if (v && !strcmp(v, "only")) {
+                       allow_fast_forward = 1;
+                       fast_forward_only = 1;
+               } /* do not barf on values from future versions of git */
+               return 0;
        } else if (!strcmp(k, "merge.defaulttoupstream")) {
                default_to_upstream = git_config_bool(k, v);
                return 0;
@@ -599,6 +608,14 @@ static void write_tree_trivial(unsigned char *sha1)
                die(_("git write-tree failed to write a tree"));
 }
 
+static const char *merge_argument(struct commit *commit)
+{
+       if (commit)
+               return sha1_to_hex(commit->object.sha1);
+       else
+               return EMPTY_TREE_SHA1_HEX;
+}
+
 int try_merge_command(const char *strategy, size_t xopts_nr,
                      const char **xopts, struct commit_list *common,
                      const char *head_arg, struct commit_list *remotes)
@@ -619,11 +636,11 @@ int try_merge_command(const char *strategy, size_t xopts_nr,
                args[i++] = s;
        }
        for (j = common; j; j = j->next)
-               args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
+               args[i++] = xstrdup(merge_argument(j->item));
        args[i++] = "--";
        args[i++] = head_arg;
        for (j = remotes; j; j = j->next)
-               args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
+               args[i++] = xstrdup(merge_argument(j->item));
        args[i] = NULL;
        ret = run_command_v_opt(args, RUN_GIT_CMD);
        strbuf_release(&buf);