Bug#843117: lintian does not warn on Essential dependencies

[Nicolas Braud-Santoni <nicolas@braud-santoni.eu>]

Package: lintian
Version: 2.5.49
Severity: normal

Dear Maintainer,

According to the Debian Policy, packages should not declare dependencies
on packages tagged Essential:

  https://www.debian.org/doc/debian-policy/ch-binary.html#s-dependencies

However, I noticed that lintian does not warn if, for instance,
one declares a dependency upon dash.


Best,

  nicoo


-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (900, 'testing'), (500, 'unstable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.6.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages lintian depends on:
ii  binutils                          2.27-9+b1
ii  bzip2                             1.0.6-8
ii  diffstat                          1.61-1
ii  file                              1:5.28-4
ii  gettext                           0.19.8.1-1
ii  intltool-debian                   0.35.0+20060710.4
ii  libapt-pkg-perl                   0.1.30
ii  libarchive-zip-perl               1.59-1
ii  libclass-accessor-perl            0.34-1
ii  libclone-perl                     0.38-2+b1
ii  libdpkg-perl                      1.18.10
ii  libemail-valid-perl               1.202-1
ii  libfile-basedir-perl              0.07-1
ii  libipc-run-perl                   0.94-1
ii  liblist-moreutils-perl            0.416-1+b1
ii  libparse-debianchangelog-perl     1.2.0-11
ii  libperl5.24 [libdigest-sha-perl]  5.24.1~rc3-3
ii  libtext-levenshtein-perl          0.13-1
ii  libtimedate-perl                  2.3000-2
ii  liburi-perl                       1.71-1
ii  libyaml-libyaml-perl              0.63-1+b1
ii  man-db                            2.7.5-1
ii  patchutils                        0.3.4-1
ii  perl                              5.24.1~rc3-3
ii  t1utils                           1.39-2
ii  xz-utils                          5.2.2-1.2

Versions of packages lintian recommends:
ii  dpkg                                 1.18.10
pn  libperlio-gzip-perl                  <none>
ii  perl                                 5.24.1~rc3-3
ii  perl-modules-5.24 [libautodie-perl]  5.24.1~rc3-3

Versions of packages lintian suggests:
pn  binutils-multiarch     <none>
ii  dpkg-dev               1.18.10
ii  libhtml-parser-perl    3.72-2+b1
ii  libtext-template-perl  1.46-1

-- no debconf information