show-caller.rb

# .pryrc
show_backtrace = Class.new(Pry::ClassCommand) do
  IGNORE_PATHS = %w[
    /pry
    /byebug
  ].freeze

  match 'show-backtrace'
  description 'Filter the caller locations'

  banner <<-'BANNER'
    Usage: show-backtrace [NUMBER]

    show-backtrace
    show-backtrace 0
  BANNER

  def process
    if input_index && filtered_backtrace[input_index]
      location = filtered_backtrace[input_index]
      edit_file(location)
    else
      show_backtrace
    end
  end

  private

  def show_backtrace
    out = filtered_backtrace.map { |location|
      path = Pathname.new(location.path)
      relative_path = relative_path_from_root(path)

      "#{relative_path}:#{location.lineno}:in `#{location.label}`"
    }.map { |line|
      "\e[31m#{line}\e[0m,"
    }.join("\n")

    _pry_.pager.page(out)
  end

  def relative_path_from_root(path)
    if defined?(Rails) && Rails.root
      path.relative_path_from(Rails.root)
    else
      path
    end
  rescue ArgumentError
    path
  end

  def edit_file(location)
    _pry_.run_command("edit #{location.path}:#{location.lineno}")
  end

  def filtered_backtrace
    # 3で、このファイルのbacktraceを無視する
    caller_locations(3).reject do |location|
      location.path =~ ignore_path_re
    end
  end

  def input_index
    arg_string.to_i unless arg_string.empty?
  end

  def ignore_path_re
    %r{(?:#{IGNORE_PATHS.join('|')})}
  end
end

Pry::Commands.add_command(show_backtrace)
Pry::Commands.alias_command '~', 'show-backtrace'