class Gem::UnsatisfiableDependencyError

def initialize(dep, platform_mismatch=nil)
  if platform_mismatch && !platform_mismatch.empty?
    plats = platform_mismatch.map {|x| x.platform.to_s }.sort.uniq
    super "Unable to resolve dependency: No match for '#{dep}' on this platform. Found: #{plats.join(", ")}"
  else
    if dep.explicit?
      super "Unable to resolve dependency: user requested '#{dep}'"
    else
      super "Unable to resolve dependency: '#{dep.request_context}' requires '#{dep}'"
    end
  end
  @dependency = dep
  @errors     = []
end