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To:Ryan Schmidt From:Chris Perl Subject:Re: Vim - Tarball with Patches vs Mercurial Date:Thu, 05 Apr 2012 16:52:25 -0400

On Thu, Apr 05, 2012 at 02:00:57PM -0500, Ryan Schmidt wrote:

> In MacPorts we would prefer to go to almost extraordinary lengths to
> use tarballs and patchfiles rather than fetching from a version
> control system. This is because we can mirror distfiles and
> patchfiles* so that in case the upstream files go away our users can
> still install the ports.

Interesting point. I hadn't thought about this.

> We also list checksums for each distfile and patchfile* so our users
> are ensured the software they're installing is the same software the
> maintainer tested.

In the case of Mercurial (or Git) you still get the same cryptographic
integrity. If you set hg.tag (or git.branch) to a specific hash
identifier, you will always be assured you're getting the same set of
files and that those files contain the same data. I am fairly sure both
tools verify hashes during normal operations, but if you want to be
extra sure, you could include a run of 'hg verify' (or 'git fsck').

I don't know the complete set of vcs's that you support, but I do know
that this does NOT apply to subversion. In that case this is perfectly
valid reason to prefer tarballs and patchfiles with listed checksums.

> If no distfiles are available and fetching from a version control
> system seems like the only solution, it would still be preferable for
> the maintainer to package up a distfile of it and upload it and make
> the port use that. But we're often lazy and resort to fetching
> directly from the vcs in those cases. Some day we might write a script
> to automate the creation of such distfiles, at which point we'll have
> fewer valid excuses.

Ok, so I guess its up to Rainer if he feels like the benefit is worth
the added effort of creating/uploading a distfile. I personally think
it is worth the effort, but then again I'm not the one that is going to
have to do it!

For everyone's benefit, here is a concrete example of how this affects
MacPorts vim. I am running vim @7.3.462_0 (the newest and most
up-to-date in MacPorts as of today). The version of netrw included with
this vim installation is 140

$ grep '^" Version' /opt/local/share/vim/vim73/autoload/netrw.vim
" Version: 140

Vim patch 462 is recorded in the vim Mercurial repo with a date of Wed
Feb 29 19:20:02 2012 +0100 (changeset 70eff6af1158). The inclusion of
netrw.vim version 140 is recorded with a date of Wed Jul 28 18:17:41
2010 +0200 (changeset e52d87a2bb3e). Since that time (but before the
date of patch 462) there have been these updates that we have missed:

141: Fri Apr 01 18:03:16 2011 +0200 (changeset b0d34143ebfc)
142: Sun Jun 19 05:09:16 2011 +0200 (changeset fd09a9c8468e)
143: Thu Oct 20 22:22:38 2011 +0200 (changeset 37ecb8ff4560)

Personally, I rarely use netrw and I have no idea if any of these
upgrades fix any critical bugs or provide any killer features. This is
just an example.

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