Merge branch 'jc/mention-tracking-for-pull-default'

[git.git] / sequencer.c

diff --git a/sequencer.c b/sequencer.c
index 22604902aa4c4dd146f562c4841c344a773a9bda..aef5e8a0170c5b337f1aa3ac7a35be3b54957729 100644 (file)
--- a/sequencer.c
+++ b/sequencer.c
@@ -186,14 +186,15 @@ static int error_dirty_index(struct replay_opts *opts)
        return -1;
 }
 
-static int fast_forward_to(const unsigned char *to, const unsigned char *from)
+static int fast_forward_to(const unsigned char *to, const unsigned char *from,
+                          int unborn)
 {
        struct ref_lock *ref_lock;
 
        read_cache();
        if (checkout_fast_forward(from, to, 1))
                exit(1); /* the callee should have complained already */
-       ref_lock = lock_any_ref_for_update("HEAD", from, 0);
+       ref_lock = lock_any_ref_for_update("HEAD", unborn ? null_sha1 : from, 0);
        return write_ref_sha1(ref_lock, to, "cherry-pick");
 }
 
@@ -390,7 +391,7 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
        struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
        char *defmsg = NULL;
        struct strbuf msgbuf = STRBUF_INIT;
-       int res;
+       int res, unborn = 0;
 
        if (opts->no_commit) {
                /*
@@ -402,9 +403,10 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
                if (write_cache_as_tree(head, 0, NULL))
                        die (_("Your index file is unmerged."));
        } else {
-               if (get_sha1("HEAD", head))
-                       return error(_("You do not have a valid HEAD"));
-               if (index_differs_from("HEAD", 0))
+               unborn = get_sha1("HEAD", head);
+               if (unborn)
+                       hashcpy(head, EMPTY_TREE_SHA1_BIN);
+               if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD", 0))
                        return error_dirty_index(opts);
        }
        discard_cache();
@@ -435,8 +437,10 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
        else
                parent = commit->parents->item;
 
-       if (opts->allow_ff && parent && !hashcmp(parent->object.sha1, head))
-               return fast_forward_to(commit->object.sha1, head);
+       if (opts->allow_ff &&
+           ((parent && !hashcmp(parent->object.sha1, head)) ||
+            (!parent && unborn)))
+            return fast_forward_to(commit->object.sha1, head, unborn);
 
        if (parent && parse_commit(parent) < 0)
                /* TRANSLATORS: The first %s will be "revert" or