module Kernel

def require path
  spec = Gem.find_unresolved_default_spec(path)
  if spec
    Gem.remove_unresolved_default_spec(spec)
    gem(spec.name)
  end
  # If there are no unresolved deps, then we can use just try
  # normal require handle loading a gem from the rescue below.
  if Gem::Specification.unresolved_deps.empty? then
    return gem_original_require(path)
  end
  # If +path+ is for a gem that has already been loaded, don't
  # bother trying to find it in an unresolved gem, just go straight
  # to normal require.
  #--
  # TODO request access to the C implementation of this to speed up RubyGems
  spec = Gem::Specification.find { |s|
    s.activated? and s.contains_requirable_file? path
  }
  return gem_original_require(path) if spec
  # Attempt to find +path+ in any unresolved gems...
  found_specs = Gem::Specification.find_in_unresolved path
  # If there are no directly unresolved gems, then try and find +path+
  # in any gems that are available via the currently unresolved gems.
  # For example, given:
  #
  #   a => b => c => d
  #
  # If a and b are currently active with c being unresolved and d.rb is
  # requested, then find_in_unresolved_tree will find d.rb in d because
  # it's a dependency of c.
  #
  if found_specs.empty? then
    found_specs = Gem::Specification.find_in_unresolved_tree path
    found_specs.each do |found_spec|
      found_spec.activate
    end
  # We found +path+ directly in an unresolved gem. Now we figure out, of
  # the possible found specs, which one we should activate.
  else
    # Check that all the found specs are just different
    # versions of the same gem
    names = found_specs.map(&:name).uniq
    if names.size > 1 then
      raise Gem::LoadError, "#{path} found in multiple gems: #{names.join ', '}"
    end
    # Ok, now find a gem that has no conflicts, starting
    # at the highest version.
    valid = found_specs.select { |s| s.conflicts.empty? }.last
    unless valid then
      le = Gem::LoadError.new "unable to find a version of '#{names.first}' to activate"
      le.name = names.first
      raise le
    end
    valid.activate
  end
  gem_original_require path
rescue LoadError => load_error
  if load_error.message.start_with?("Could not find") or
      (load_error.message.end_with?(path) and Gem.try_activate(path)) then
    return gem_original_require(path)
  end
  raise load_error
end