M-x gnus C-x C-f TAB results in stacktrace when ffap is active

[Benjamin Rutt]

This bug report will be sent to the Free Software Foundation,
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Please write in English, because the Emacs maintainers do not have
translators to read other languages for them.

In GNU Emacs 20.7.1 (i386-redhat-linux-gnu, X toolkit)
 of Tue Jun 13 2000 on porky.devel.redhat.com
configured using `configure  --mandir=/usr/man --infodir=/usr/info 
--prefix=/usr --libexecdir=/usr/lib --sharedstatedir=/var --with-gcc --with-pop 
--with-x-toolkit i386-redhat-linux-gnu'

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

I get a stacktrace after firing up emacs, typing M-x gnus C-x C-f TAB.

Note that I have ffap-bindings in effect with the following in my
.emacs:

(require 'ffap)
(ffap-bindings)

After typing M-x gnus C-x C-f, only '~' appeared by default in the
minibuffer, at which point I hit TAB and produced the stacktrace.

If I just fire up emacs and type C-x C-f, '~/' appears in the
minibuffer.  If I C-b C-d to delete the '/', leaving just '~', and
then hit TAB to try to dupe the bug, it doesn't dupe.  So maybe the
bug is somehow connected to my having executed M-x gnus?  Of course,
this is probably only a coincidence.

I also noticed that if I comment out the ffap lines above in my
.emacs, I cannot dupe the bug.

Here is the stacktrace:
Signaling: (wrong-type-argument stringp nil)
  read-file-name-internal("~" nil nil)
  ffap-read-file-or-url-internal("~" nil nil)
  minibuffer-complete()
* call-interactively(minibuffer-complete)
  completing-read("Find file or URL: " ffap-read-file-or-url-internal nil nil 
"~" (file-name-history))
  ffap-read-file-or-url("Find file or URL: " "")
  byte-code("ƒ        
  ffap-prompter()
  find-file-at-point()
* call-interactively(find-file-at-point)

Is the problem the fact that ffap-read-file-or-url-internal is passing
nil and nil for the DIR and ACTION arguments to
read-file-name-internal?




Recent input:
M-x t o g g l e - d e b u g - o n - e r r o r return 
M-x g n u s return C-x C-f tab M-x r e p o tab r t 
- e m tab return

Recent messages:
Loading gnus-topic...done
Loading debug...
Loading debug...done
Entering debugger...
 [2 times]
Making completion list...
Loading view...
Loading view...done
Loading emacsbug...
Loading emacsbug...done

-- 
Benjamin