Merge branch 'jc/push-reject-reasons'

Improve error and advice messages given locally when "git push"
refuses when it cannot compute fast-forwardness by separating these
cases from the normal "not a fast-forward; merge first and push
again" case.

* jc/push-reject-reasons:
  push: finishing touches to explain REJECT_ALREADY_EXISTS better
  push: introduce REJECT_FETCH_FIRST and REJECT_NEEDS_FORCE
  push: further simplify the logic to assign rejection reason
  push: further clean up fields of "struct ref"

1 files changed, 19 insertions, 23 deletions

diff --git a/remote.c b/remote.c
index 9e21b1d78..e53a6eb77 100644
--- a/remote.c
+++ b/remote.c
@@ -1317,28 +1317,23 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
 		 *     passing the --force argument
 		 */
 
-		ref->update =
-			!ref->deletion &&
-			!is_null_sha1(ref->old_sha1);
-
-		if (ref->update) {
-			ref->nonfastforward =
-				!has_sha1_file(ref->old_sha1)
-				  || !ref_newer(ref->new_sha1, ref->old_sha1);
-
-			if (!prefixcmp(ref->name, "refs/tags/")) {
-				ref->requires_force = 1;
-				if (!force_ref_update) {
-					ref->status = REF_STATUS_REJECT_ALREADY_EXISTS;
-					continue;
-				}
-			} else if (ref->nonfastforward) {
-				ref->requires_force = 1;
-				if (!force_ref_update) {
-					ref->status = REF_STATUS_REJECT_NONFASTFORWARD;
-					continue;
-				}
-			}
+		if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
+			int why = 0; /* why would this push require --force? */
+
+			if (!prefixcmp(ref->name, "refs/tags/"))
+				why = REF_STATUS_REJECT_ALREADY_EXISTS;
+			else if (!has_sha1_file(ref->old_sha1))
+				why = REF_STATUS_REJECT_FETCH_FIRST;
+			else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
+				 !lookup_commit_reference_gently(ref->new_sha1, 1))
+				why = REF_STATUS_REJECT_NEEDS_FORCE;
+			else if (!ref_newer(ref->new_sha1, ref->old_sha1))
+				why = REF_STATUS_REJECT_NONFASTFORWARD;
+
+			if (!force_ref_update)
+				ref->status = why;
+			else if (why)
+				ref->forced_update = 1;
 		}
 	}
 }
@@ -1532,7 +1527,8 @@ int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
 	struct commit_list *list, *used;
 	int found = 0;
 
-	/* Both new and old must be commit-ish and new is descendant of
+	/*
+	 * Both new and old must be commit-ish and new is descendant of
 	 * old.  Otherwise we require --force.
 	 */
 	o = deref_tag(parse_object(old_sha1), NULL, 0);