Bug#795383: please add a License field parser to the copyright module

[Stefano Zacchiroli]

Package: python-debian
Version: 0.1.27
Severity: wishlist

The debian.copyright module returns the content of the License field as a
string, matching the literal value written down in the debian/copyright file.

It would be nice (and will avoid duplicate work) if the module would offer a
way to traverse the content of the License field as an AST, conformant to the
semantics of machine-readable debian/copyright files.

The AST should include at the very minimum boolean and/or combination of
licenses (implementing the semantics of "," properly). Additionally, the AST
could distinguish between trailing "+" for "or later" license variants, and
support "with" for license exceptions.

FWIW, Debsources would use this feature for rendering machine-readable
copyright fiels if it were available.

Cheers.

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

Kernel: Linux 4.0.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=it_IT.utf8, LC_CTYPE=it_IT.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages python-debian depends on:
ii  python-chardet  2.3.0-1
ii  python-six      1.9.0-3
pn  python:any      <none>

Versions of packages python-debian recommends:
ii  python-apt  1.0.0~beta3

Versions of packages python-debian suggests:
ii  gpgv  1.4.19-3

-- no debconf information