Bug#848947: bibtool: [Regression] Empty separators cause errors

[GI <gi1242+debianbugs@gmail.com>]

Package: bibtool
Version: 2.66+ds-1
Severity: normal

Dear Maintainer,

With version 2.66 empty separators cause an error. For instance, using

    fmt.name.name = {}

returns an error of "Invalid separator specification" and doesn't change
the default value of fmt.name.name. This was not a problem with the
previous version of bibtool.

I suspect (but am not completely sure) that this is a regression in
upstream caused by the commit 8221dced10ebb5427f98a6d602dbcfd43409eff2.

Thanks,

GI

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.8.0-2-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US, LC_CTYPE=en_US (charmap=ISO-8859-1)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages bibtool depends on:
ii  libc6         2.24-8
ii  libkpathsea6  2016.20160513.41080-8
ii  tex-common    6.05

Versions of packages bibtool recommends:
ii  texlive-base  2016.20161130-1

bibtool suggests no packages.

-- no debconf information