module Bundler::VersionRanges

def self.for(requirement)
  ranges = requirement.requirements.map do |op, v|
    case op
    when "=" then ReqR.new(ReqR::Endpoint.new(v, true), ReqR::Endpoint.new(v, true))
    when "!=" then NEq.new(v)
    when ">=" then ReqR.new(ReqR::Endpoint.new(v, true), ReqR::Endpoint.new(ReqR::INFINITY, false))
    when ">" then ReqR.new(ReqR::Endpoint.new(v, false), ReqR::Endpoint.new(ReqR::INFINITY, false))
    when "<" then ReqR.new(ReqR::Endpoint.new(ReqR::ZERO, true), ReqR::Endpoint.new(v, false))
    when "<=" then ReqR.new(ReqR::Endpoint.new(ReqR::ZERO, true), ReqR::Endpoint.new(v, true))
    when "~>" then ReqR.new(ReqR::Endpoint.new(v, true), ReqR::Endpoint.new(v.bump, false))
    else raise "unknown version op #{op} in requirement #{requirement}"
    end
  end.uniq
  ranges, neqs = ranges.partition {|r| !r.is_a?(NEq) }
  [ranges.sort, neqs.map(&:version)]
end