class RSpec::Core::RakeTask

def blank
  lambda { |s| s.nil? || s == "" }
end

def define(args, &task_block)
  desc "Run RSpec code examples" unless ::Rake.application.last_comment
  task name, *args do |_, task_args|
    RakeFileUtils.__send__(:verbose, verbose) do
      task_block.call(*[self, task_args].slice(0, task_block.arity)) if task_block
      run_task verbose
    end
  end
end

def file_exclusion_specification
  " --exclude-pattern #{exclude_pattern.shellescape}" if exclude_pattern
end

def file_inclusion_specification
  if ENV['SPEC']
    FileList[ ENV['SPEC']].sort
  elsif Array === pattern || File.exist?(pattern)
    # Before RSpec 3.1, we used `FileList` to get the list of matched files, and
    # then pass that along to the `rspec` command. Starting with 3.1, we prefer to
    # pass along the pattern as-is to the `rspec` command, for 3 reasons:
    #
    #   * It's *much* less verbose to pass one `--pattern` option than a long list of files.
    #   * It ensures `task.pattern` and `--pattern` have the same behavior.
    #   * It fixes a bug, where `task.pattern = pattern_that_matches_no_files` would run
    #     *all* files because it would cause no pattern or file args to get passed to `rspec`,
    #     which causes all files to get run.
    #
    # However, `FileList` is *far* more flexible than the `--pattern` option. Specifically, it
    # supports individual files and directories, as well as arrays of files, directories and globs.
    #
    # For backwards compatibility, we have to fall back to using FileList if the user has passed
    # a `pattern` option that will not work with `--pattern`.
    #
    # TODO: consider deprecating support for this and removing it in RSpec 4.
    FileList[pattern].sort.map(&:shellescape)
  else
    "--pattern #{pattern.shellescape}"
  end
end

def initialize(*args, &task_block)
  @name          = args.shift || :spec
  @ruby_opts     = nil
  @rspec_opts    = nil
  @verbose       = true
  @fail_on_error = true
  @rspec_path    = DEFAULT_RSPEC_PATH
  @pattern       = DEFAULT_PATTERN
  define(args, &task_block)
end

def rspec_load_path
  @rspec_load_path ||= begin
    core_and_support = $LOAD_PATH.grep(
      /#{File::SEPARATOR}rspec-(core|support)[^#{File::SEPARATOR}]*#{File::SEPARATOR}lib/
    )
    "-I#{core_and_support.map(&:shellescape).join(File::PATH_SEPARATOR)}"
  end
end

def run_task(verbose)
  command = spec_command
  begin
    puts command if verbose
    success = system(command)
  rescue
    puts failure_message if failure_message
  end
  return unless fail_on_error && !success
  $stderr.puts "#{command} failed"
  exit $?.exitstatus
end

def spec_command
  cmd_parts = []
  cmd_parts << RUBY
  cmd_parts << ruby_opts
  cmd_parts << rspec_load_path
  cmd_parts << rspec_path
  cmd_parts << file_inclusion_specification
  cmd_parts << file_exclusion_specification
  cmd_parts << rspec_opts
  cmd_parts.flatten.reject(&blank).join(" ")
end