bug#21851: ediff-patch-file fails if patch-buf is a buffer nameif patch-buf is a buffer name

[Tino Calancha]

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ediff-patch-file fails if patch-buf is a buffer name

* lisp/vc/ediff.el (ediff-patch-file)

emacs -Q:
(in *scratch* buffer)

(with-temp-file "/tmp/buff"
  (insert "foo bar"))

(with-current-buffer (generate-new-buffer "buff2")
  (insert "foo baz"))

;; call ediff-buffers on "buff" and "buff2" and save the
;; differences in a buffer "patch"

(epatch nil (get-buffer "patch")) ; ok
(epatch nil "patch") ; BAD
epatch: Wrong type argument: bufferp, "patch"


Emacs  : GNU Emacs 25.0.50.1 (x86_64-pc-linux-gnu, GTK+ Version 2.24.28)
 of 2015-11-07
Package: Ediff 2.81.5 of July 4, 2013

ediff_1.patch
Description: Text document