continue;
}
- /* This part determines what can overwrite what.
- * The rules are:
+ /*
+ * The below logic determines whether an individual
+ * refspec A:B can be pushed. The push will succeed
+ * if any of the following are true:
*
- * (0) you can always use --force or +A:B notation to
- * selectively force individual ref pairs.
+ * (1) the remote reference B does not exist
*
- * (1) if the old thing does not exist, it is OK.
+ * (2) the remote reference B is being removed (i.e.,
+ * pushing :B where no source is specified)
*
- * (2) if the destination is under refs/tags/ you are
- * not allowed to overwrite it; tags are expected
- * to be static once created
+ * (3) the update meets all fast-forwarding criteria:
*
- * (3) if you do not have the old thing, you are not allowed
- * to overwrite it; you would not know what you are losing
- * otherwise.
+ * (a) the destination is not under refs/tags/
+ * (b) the old is a commit
+ * (c) the new is a descendant of the old
*
- * (4) if old is a commit and new is a descendant of old
- * (implying new is commit-ish), it is OK.
+ * NOTE: We must actually have the old object in
+ * order to overwrite it in the remote reference,
+ * and the new object must be commit-ish. These are
+ * implied by (b) and (c) respectively.
*
- * (5) regardless of all of the above, removing :B is
- * always allowed.
+ * (4) it is forced using the +A:B notation, or by
+ * passing the --force argument
*/
ref->not_forwardable = !is_forwardable(ref);