copy: add experimental support for marking committed copies The simplest way I'm aware of to mark a file as copied/moved after committing is this: hg uncommit --keep <src> <dest> # <src> needed for move, but not copy hg mv --after <src> <dest> hg amend This patch teaches `hg copy` a `--at-rev` argument to simplify that into: hg copy --after --at-rev . <src> <dest> In addition to being simpler, it doesn't touch the working copy, so it can easily be used even if the destination file has been modified in the working copy. Differential Revision: https://phab.mercurial-scm.org/D8035

--- a/relnotes/next	Thu Dec 26 14:02:50 2019 -0800
+++ b/relnotes/next	Fri Dec 20 13:24:46 2019 -0800
@@ -14,8 +14,12 @@
 
  * `hg copy --forget` can be used to unmark a file as copied.
 
+== New Experimental Features ==
 
-== New Experimental Features ==
+ * `hg copy` now supports a `--at-rev` argument to mark files as
+   copied in the specified commit. It only works with `--after` for
+   now (i.e., it's only useful for marking files copied using non-hg
+   `cp` as copied).
 
  * Use `hg copy --forget --at-rev REV` to unmark already committed
    copies.