Bug#787248: should not yield dep5-copyright-license-name-not-unique for multiple public-domain sections

[Evgeni Golov <evgeni@debian.org>]

Package: lintian
Version: 2.5.31
Severity: minor

Hi,

"public-domain" has a special meaning in DEP5, [1] states: "When the License
field in a paragraph has the short name public-domain, the remaining lines of
the field must explain exactly what exemption the corresponding files for
that paragraph have from default copyright restrictions."

This, I think, it is toally legal to have multiple stanzas in d/copyright,
all saying "License: public-domain" and then stating why the work is PD.

However, lintian will currently tag such a d/copyright with
 dep5-copyright-license-name-not-unique
as "public-domain" is used multiple times with different long-texts.

We should special-case public-domain here probably.

Regards
Evgeni

[1] https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'stable'), (500, 'oldstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.19.0-trunk-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages lintian depends on:
ii  binutils                       2.25-8
ii  bzip2                          1.0.6-8
ii  diffstat                       1.58-1
ii  file                           1:5.22+15-2
ii  gettext                        0.19.4-1
ii  hardening-includes             2.7
ii  intltool-debian                0.35.0+20060710.2
ii  libapt-pkg-perl                0.1.29+b2
ii  libarchive-zip-perl            1.39-1
ii  libclass-accessor-perl         0.34-1
ii  libclone-perl                  0.38-1
ii  libdpkg-perl                   1.18.1
ii  libemail-valid-perl            1.195-1
ii  libfile-basedir-perl           0.03-1
ii  libipc-run-perl                0.94-1
ii  liblist-moreutils-perl         0.410-1
ii  libparse-debianchangelog-perl  1.2.0-3
ii  libtext-levenshtein-perl       0.12-1
ii  libtimedate-perl               2.3000-2
ii  liburi-perl                    1.64-1
ii  man-db                         2.7.0.2-5
ii  patchutils                     0.3.4-1
ii  perl [libdigest-sha-perl]      5.20.2-6
ii  t1utils                        1.38-4
ii  xz-utils                       5.1.1alpha+20120614-2+b3

Versions of packages lintian recommends:
ii  dpkg                            1.18.1
ii  libautodie-perl                 2.25-1
ii  libperlio-gzip-perl             0.18-3+b1
ii  perl                            5.20.2-6
ii  perl-modules [libautodie-perl]  5.20.2-6

Versions of packages lintian suggests:
pn  binutils-multiarch     <none>
ii  dpkg-dev               1.18.1
ii  libhtml-parser-perl    3.71-1+b3
ii  libtext-template-perl  1.46-1
ii  libyaml-perl           1.13-1

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