From h@w|ckh@m @end|ng |rom gm@||@com  Sat Sep 12 01:06:19 2020
From: h@w|ckh@m @end|ng |rom gm@||@com (Hadley Wickham)
Date: Fri, 11 Sep 2020 18:06:19 -0500
Subject: [Rd] Including full text of open source licenses in a package
Message-ID: <CABdHhvF+daTK6T1f7W3T+6qXpZt1H140ekSh2F5t+f=20=x1gA@mail.gmail.com>

Hi all,

R-exts currently requests that package authors don't include copies of
standard licenses:

> Whereas you should feel free to include a license file in your source distribution, please do
> not arrange to install yet another copy of the GNU COPYING or COPYING.LIB files but
> refer to the copies on https://www.R-project.org/Licenses/ and included in the R distribution
> (in directory share/licenses). Since files named LICENSE or LICENCE will be installed,
> do not use these names for standard license files.

I'd like to request that this condition be removed because it makes it
overly difficult to ensure that every version of your package (source,
tar.gz, binary, and installed) includes the full text of the license.
This is important because most open source licenses explicitly require
that you include the full text of the license. For example, the GPL
faq (http://www.gnu.org/licenses/gpl-faq.html#WhyMustIInclude) states:

> Why does the GPL require including a copy of the GPL with every copy of the program?
> (#WhyMustIInclude)
>
> Including a copy of the license with the work is vital so that everyone who gets a copy of
> the program can know what their rights are.
>
> It might be tempting to include a URL that refers to the license, instead of the license
> itself. But you cannot be sure that the URL will still be valid, five years or ten years from
> now. Twenty years from now, URLs as we know them today may no longer exist.
>
> The only way to make sure that people who have copies of the program will continue
> to be able to see the license, despite all the changes that will happen in the network,
> is to include a copy of the license in the program.

This analysis by an open source lawyer,
https://writing.kemitchell.com/2016/09/21/MIT-License-Line-by-Line.html#notice-condition,
reinforces the same message for the MIT license.

Currently we've been working around this limitation by putting a
markdown version of the license in LICENSE.md and then adding that to
.Rbuildignore (this ensures that the source version on GitHub includes
the license even if the CRAN version does not). Ideally, as well as
allowing us to include full text of licenses in LICENSE or
LICENSE.txt, a LICENSE.md at the top-level of the package would also
be explicitly permitted.

Hadley

-- 
http://hadley.nz



[Rd] Including full text of open source licenses in a package
Hadley Wickham