master 615f06ea534: fix for bibtex.el in prior commit

[Roland Winkler]

branch: master
commit 615f06ea534cd565f439b08d563a31ca2b0eea92
Author: Roland Winkler <winkler@gnu.org>
Commit: Roland Winkler <winkler@gnu.org>

    fix for bibtex.el in prior commit
    
    * lisp/textmodes/bibtex.el (bibtex-string-file-path)
    (bibtex-file-path): Check for undefined environment variable
    BIBINPUTS.
---
 lisp/textmodes/bibtex.el | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lisp/textmodes/bibtex.el b/lisp/textmodes/bibtex.el
index 83d8f2e6e70..a337c7167ca 100644
--- a/lisp/textmodes/bibtex.el
+++ b/lisp/textmodes/bibtex.el
@@ -1095,7 +1095,9 @@ to the directories specified in 
`bibtex-string-file-path'."
   :group 'bibtex
   :type '(repeat file))
 
-(defcustom bibtex-string-file-path (split-string (getenv "BIBINPUTS") ":+" t)
+(defcustom bibtex-string-file-path
+  (let ((bibinputs (getenv "BIBINPUTS")))
+    (if bibinputs (split-string bibinputs ":+" t)))
   "List of directories to search for `bibtex-string-files'.
 By default, initialized from the BIBINPUTS environment variable.
 For backward compatibility, considered obsolete, it may also be
@@ -1117,7 +1119,9 @@ See also `bibtex-search-entry-globally'."
   :type '(repeat (choice (const :tag "bibtex-file-path" bibtex-file-path)
                          directory file)))
 
-(defcustom bibtex-file-path (split-string (getenv "BIBINPUTS") ":+" t)
+(defcustom bibtex-file-path
+  (let ((bibinputs (getenv "BIBINPUTS")))
+    (if bibinputs (split-string bibinputs ":+" t)))
   "List of directories to search for `bibtex-files'.
 By default, initialized from the BIBINPUTS environment variable.
 For backward compatibility, considered obsolete, it may also be