In guix master, emacs-magit-svn has a build failure:

magit-svn-2.2.0/
magit-svn-2.2.0/README.md
magit-svn-2.2.0/magit-svn.el
Backtrace:
           3 (primitive-load "/gnu/store/ckrmzdnzpbgh3c0nc4q7swl1x2z?")
In ice-9/eval.scm:
   191:35  2 (_ #f)
    619:8  1 (_ #(#(#(#(#(#(#(#(#<directory ?> ?) ?) ?) ?) ?) ?) ?) ?))
In unknown file:
           0 (copy-file "emacs-magit-svn-2.2.0/magit-svn.el" "/gnu/s?")

ERROR: In procedure copy-file:
In procedure copy-file: No such file or directory