receive: denyCurrentBranch=updateinstead should not blindly update

The handling of receive.denyCurrentBranch=updateInstead was added to
a switch statement that handles other values of the variable, but
all the other case arms only checked a condition to reject the
attempted push, or let later logic in the same function to still
intervene, so that a push that does not fast-forward (which is
checked after the switch statement in question) is still rejected.

But the handling of updateInstead incorrectly took immediate effect,
without giving other checks a chance to intervene.

Instead of calling update_worktree() that causes the side effect
immediately, just note the fact that we will need to call the
function later, and first give other checks a chance to reject the
request.  After the update-hook gets a chance to reject the push
(which happens as the last step in a series of checks), call
update_worktree() when we earlier detected the need to.

Reported-by: Rajesh Madamanchi
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 68d36e0a56c3c72ad76c07af293d20e8254377d1..d28a35c9920b84a3c527f333fd5aa3998f1a3630 100644 (file)
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -1037,6 +1037,7 @@ static const char *update(struct command *cmd, struct shallow_info *si)
        const char *ret;
        struct object_id *old_oid = &cmd->old_oid;
        struct object_id *new_oid = &cmd->new_oid;
+       int do_update_worktree = 0;
 
        /* only refs/... are allowed */
        if (!starts_with(name, "refs/") || check_refname_format(name + 5, 0)) {
@@ -1062,9 +1063,8 @@ static const char *update(struct command *cmd, struct shallow_info *si)
                                refuse_unconfigured_deny();
                        return "branch is currently checked out";
                case DENY_UPDATE_INSTEAD:
-                       ret = update_worktree(new_oid->hash);
-                       if (ret)
-                               return ret;
+                       /* pass -- let other checks intervene first */
+                       do_update_worktree = 1;
                        break;
                }
        }
@@ -1129,6 +1129,12 @@ static const char *update(struct command *cmd, struct shallow_info *si)
                return "hook declined";
        }
 
+       if (do_update_worktree) {
+               ret = update_worktree(new_oid->hash);
+               if (ret)
+                       return ret;
+       }
+
        if (is_null_oid(new_oid)) {
                struct strbuf err = STRBUF_INIT;
                if (!parse_object(old_oid)) {

diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index a5077d8b7c596523a3b0e0e5e45385e5d7871b9e..1a67f479769d71db2b9c90f5345f3a0202bdcfa3 100755 (executable)
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -1527,7 +1527,13 @@ test_expect_success 'receive.denyCurrentBranch = updateInstead' '
                test $(git -C .. rev-parse master) = $(git rev-parse HEAD) &&
                git diff --quiet &&
                git diff --cached --quiet
-       )
+       ) &&
+
+       # (6) updateInstead intervened by fast-forward check
+       test_must_fail git push void master^:master &&
+       test $(git -C void rev-parse HEAD) = $(git rev-parse master) &&
+       git -C void diff --quiet &&
+       git -C void diff --cached --quiet
 '
 
 test_expect_success 'updateInstead with push-to-checkout hook' '