class Bundler::Index

def search_by_dependency(dependency, base = nil)
  @cache[base || false] ||= {}
  @cache[base || false][dependency] ||= begin
    specs = specs_by_name(dependency.name)
    specs += base if base
    found = specs.select do |spec|
      next true if spec.source.is_a?(Source::Gemspec)
      if base # allow all platforms when searching from a lockfile
        dependency.matches_spec?(spec)
      else
        dependency.matches_spec?(spec) && Gem::Platform.match(spec.platform)
      end
    end
    found
  end
end