Mine

%define ruby_sitelib %(ruby -rrbconfig -e "puts Config::CONFIG['sitelibdir']")
%define gemdir %(ruby -rubygems -e 'puts Gem::dir' 2>/dev/null)
%define gemname rails
%define geminstdir %{gemdir}/gems/%{gemname}-%{version}

Summary: Web-application framework
Name: rubygem-%{gemname}
Version: 2.3.3
Release: 1
Group: Development/Languages
License: MIT
URL: http://www.rubyonrails.org
Source0: http://gems.rubyforge.org/gems/%{gemname}-%{version}.gem
BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
Requires: rubygems >= 1.1.1
Requires: rubygem-rake >= 0.8.3
Requires: rubygem-activesupport = %{version}
Requires: rubygem-activerecord = %{version}
Requires: rubygem-actionpack = %{version}
Requires: rubygem-actionmailer = %{version}
Requires: rubygem-activeresource = %{version}

BuildRequires: rubygems

BuildArch: noarch

%description
Rails is a framework for building web-application using CGI, FCGI, mod_ruby,
or WEBrick on top of either MySQL, PostgreSQL, SQLite, DB2, SQL Server, or
Oracle with eRuby- or Builder-based templates.


%prep

%install
rm -rf %{buildroot}
mkdir -p %{buildroot}%{gemdir}
gem install --local --install-dir %{buildroot}%{gemdir} \
            -V \
            --force %{SOURCE0}
mkdir -p %{buildroot}/%{_bindir}
mv %{buildroot}%{gemdir}/bin/* %{buildroot}/%{_bindir}
rmdir %{buildroot}%{gemdir}/bin
find %{buildroot}%{geminstdir}/bin -type f | xargs chmod a+x

sed -i '1i#!/usr/bin/ruby\n' %{buildroot}%{geminstdir}/bin/rails

for file in `find %{buildroot}/%{geminstdir}/ -type f -perm /a+x`; do
  sed -i -e '1s|%{_bindir}/env ruby|%{_bindir}/ruby|' $file
  chmod 755 $file
done

find %{buildroot}/%{geminstdir} -type f -name "*~" -delete

#find %{buildroot}/%{geminstdir} -type f -size 0c -exec rm -rvf {} \;

for file in `find %{buildroot}/%{geminstdir} -type f -perm /a+x`; do
    [ -z "`head -n 1 $file | grep \"^#!/\"`" ] && chmod -v 644 $file
done

# For sure...
find %{buildroot} -name \*.gem | xargs chmod 0644

# Find files with a shebang that do not have executable permissions
for file in `find %{buildroot}/%{geminstdir} -type f ! -perm /a+x -name "*.rb"`; do
    [ ! -z "`head -n 1 $file | grep \"^#!/\"`" ] && chmod -v 755 $file
done

# Find files that have non-standard-executable-perm
find %{buildroot}/%{geminstdir} -type f -perm /g+wx -exec chmod -v g-w {} \;

# Find files that are not readable
find %{buildroot}/%{geminstdir} -type f ! -perm /go+r -exec chmod -v go+r {} \;

%clean
rm -rf %{buildroot}

%files
%defattr(-, root, root, -)
%dir %{geminstdir}
%{geminstdir}/bin
%{geminstdir}/builtin
%doc %{geminstdir}/CHANGELOG
%{geminstdir}/configs
%{geminstdir}/dispatches
%{geminstdir}/doc
%{geminstdir}/environments
%{geminstdir}/fresh_rakefile
%{geminstdir}/guides
%{geminstdir}/helpers
%{geminstdir}/html
%{geminstdir}/lib
%doc %{geminstdir}/MIT-LICENSE
%{geminstdir}/Rakefile
%doc %{geminstdir}/README
%{_bindir}/rails
%{gemdir}/cache/%{gemname}-%{version}.gem
%{gemdir}/specifications/%{gemname}-%{version}.gemspec