bug#23646: 25.0.94; file-name-completion does not handle completion-ignored-extensions properly

[Michael Albinus]

Try the following:

(let ((completion-ignored-extensions ".ext"))
  (write-region "foo" nil (expand-file-name "foo" "/tmp"))
  (write-region "foo" nil (expand-file-name "foo.ext" "/tmp"))
  (file-name-all-completions "fo" "/tmp") ; ("foo" "foo.ext"), OK
  (file-name-completion "fo" "/tmp") ; "foo", OK
  (file-name-completion "foo" "/tmp") ; "foo", NOK, should be t
  (file-name-completion "foo." "/tmp") ; "foo.ext", OK
  (file-name-completion "foo.ext" "/tmp")) ; t, OK



In GNU Emacs 25.0.94.4 (x86_64-pc-linux-gnu, GTK+ Version 2.24.30)
 of 2016-05-29 built on detlef
Repository revision: bffda223c210832f535e753585235a791fb6e2f3
Windowing system distributor 'The X.Org Foundation', version 11.0.11803000
System Description:     Ubuntu 16.04 LTS

Configured features:
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LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB TOOLKIT_SCROLL_BARS GTK2 X11

Important settings:
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Major mode: Lisp Interaction

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Recent messages:
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