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 #{escape exclude_pattern}" if exclude_pattern
end

def file_inclusion_specification
  if ENV['SPEC']
    FileList[ ENV['SPEC']].sort
  elsif String === pattern && !File.exist?(pattern)
    "--pattern #{escape pattern}"
  else
    # 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, as well as other
    # `FileList` objects.
    #
    # 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 { |file| escape file }
  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/
    ).uniq
    "-I#{core_and_support.map { |file| escape file }.join(File::PATH_SEPARATOR)}"
  end
end

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

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