rename: add support for --at-rev, which marks as copy and removes the source I had previously only added support for `--at-rev` to `hg cp`, but not to `hg mv`. This patch adds that support. Just like for `hg cp`, it marks the destination as copied from the source, and doesn't care if the source file still exists (because it only supports the `-A` mode, aka "don't touch files" mode). It works whether or not the source file still exists. This matches the behavior of `hg mv -A` in the working copy. Differential Revision: https://phab.mercurial-scm.org/D8840

--- a/relnotes/next	Fri Jul 24 15:03:14 2020 -0700
+++ b/relnotes/next	Tue Jul 28 09:58:28 2020 -0700
@@ -1,5 +1,9 @@
 == New Features ==
 
+ * `hg mv -A` can now be used with `--at-rev`. It behaves just like
+   `hg cp -A --at-rev`, i.e. it marks the destination as a copy of the
+   source whether or not the source still exists (but the source must
+   exist in the parent revision).
 
 
 == New Experimental Features ==