The Debian packaging of magit-annex is maintained using dgit.  For the
sake of an efficient workflow, Debian modifications to the upstream
source are squashed into a single diff, rather than a series of quilt
patches.  To obtain a patch queue for package version 1.2.3-1:

    # apt-get install dgit
    % dgit clone magit-annex
    % cd magit-annex
    % git log --oneline 1.2.3..debian/1.2.3-1 -- . ':!debian'

See dgit(1), dgit(7) and dgit-maint-merge(7) for more information.
--- magit-annex-1.9.0.orig/magit-annex-tests.el
+++ magit-annex-1.9.0/magit-annex-tests.el
@@ -78,7 +78,7 @@
              (magit-call-git "init" ".")
              (magit-call-git "annex" "init" "repo1")
              (magit-annex-tests-modify-file "file")
-             (magit-stage-file "file")
+             (magit-stage-files (list "file"))
              (magit-call-git "commit" "-m" "normal commit")
              (magit-call-git "remote" "add" "repo2" repo2))
            (let ((default-directory repo2))
