[Rubyinstaller-devel] Gem compatibility and platform specific dependencies
luislavena at gmail.com
Fri Apr 25 00:21:02 EDT 2008
On Fri, Apr 25, 2008 at 1:01 AM, Gordon Thiesfeld <gthiesfeld at gmail.com> wrote:
> This may be better asked on the RubyGems list, but I thought I'd try
> here first. I'm working on a patch for the github gem. The
> github command requires open3, which doesn't work on Windows because
> of fork, so I have it check for platform, and require WIn32-Open3 if
> on Windows. So, I have two questions about how to go about this.
> First, is Gem.win_platform? the proper way to go about this. I think
> it's safe to say this package will always be distributed as a gem, so
> Gem will always exist when I need it.
I think is safe to assume Gem.win_platform? is available since you're
implementing that into a project that get's distributed/installed as
The only problem is that win_platform? will be 'true' even for cygwin
implementation, which will render win32/open3 useless and I can smell
that will crash :-P
> Second, is there a way to have Gem depedencies that are platform
> specific? Open3 is part of the stdlib, so no dependency there, but on
> Windows we need the Win32 gem. I've borrowed a pattern from RSpec for
To our bad, there isn't a way to do that, you can create a
"windows-specific" version and in that gem include the dependencies,
but without a real need to do that, I think workaround in the code
should be used.
> require 'win32 package'
> rescue LoadError
> warn "You must 'gem install the win32 package to do this on Windows"
> exit 1
> But in the case of RSpec, it's only used for colored console output.
> If you don't use that feature, you'll never know you need to have the
> gem installed. In this case, the whole thing just won't work.
> That's what dependencies are all about, I'd think. If there isn't
> such a thing as platform specific dependencies, then what I'm fine
> doing it this way. I'm just wondering if there's a better way.
A good workaround will be poke the ruby-core developers to merge
win32/open3 package in and reduce our code cluttery, but I don't see
that will happen anytime soon :-P
Thanks to you Gordon!
BTW: just pushed installer3 into the repository:
Human beings, who are almost unique in having the ability to learn from
the experience of others, are also remarkable for their apparent
disinclination to do so.
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