path: allow to copy a path while adjusting the url
This will be used by `scheme` in the next changesets.
Set up $ hg init repo $ cd repoTry to import an empty patch $ hg import --no-commit - <<EOF > EOF applying patch from stdin abort: stdin: no diffs found [10]No dirstate backups are left behind $ ls .hg/dirstate* | sort .hg/dirstate