why do source rpms have "prep" dependencies?

[Andy Green]

Somebody in the thread at some point said:
> On Sun, 9 Sep 2007, Frank Cox wrote:
> 
>> On Sun, 09 Sep 2007 03:47:33 -0400 (EDT)
>> "Robert P. J. Day" <rpjday at mindspring.com> wrote:
>>
>>> if someone wants to simply RTFS, it's a bit disconcerting to learn
>>> that you need to download another five source rpms to do it.
>> I don't know if this is useful in your situation, but I'm pretty
>> sure File Roller can "look inside" of srpm files and extract the
>> contents for you as desired.
> 
> that might come in handy, but it still doesn't solve the fundamental
> problem of why a source rpm's "BuildRequires" value should affect the
> simple tarball extraction and patch application operation.
> 
> just for fun, i edited mkinitrd's spec file and deleted all the
> "BuildRequires" lines, and the build prep worked just fine, so i'm
> convinced that a simple prep should be possible without taking the
> BuildRequires dependencies into account.  now i just want an option
> that implements that.
> 
> well ... what are you just sitting there for?  get to work.  :-)

Not sure I got the point across that the %prep section in the spec can
contain arbitrary commands, not just %setup and %patch.  Those arbitrary
commands might be executing things that are provided by the BuildRequires.

You can then say, well, it should look at %prep and decide whether to
pull the BuildRequires in or not, but that sounds like a bad idea in
terms of complexity for a crummy "feature".  You're presumably planning
to rebuild the thing at some point anyway.

BTW there is yum localinstall that takes care of requires, maybe it or a
relative can also do the same on SRPM BuildRequires?  Never tried it.

-Andy