module Padrino

  # List of callers in a Padrino application that should be ignored as part of a stack trace.
  PADRINO_IGNORE_CALLERS = [
    %r{lib/padrino-.*$},                             # all padrino code
    %r{/padrino-.*/(lib|bin)},                       # all padrino code
    %r{/bin/padrino$},                               # all padrino code
    %r{/sinatra(/(base|main|showexceptions))?\.rb$}, # all sinatra code
    %r{lib/tilt.*\.rb$},                             # all tilt code
    %r{lib/rack.*\.rb$},                             # all rack code
    %r{lib/mongrel.*\.rb$},                          # all mongrel code
    %r{lib/shotgun.*\.rb$},                          # all shotgun lib
    %r{bin/shotgun$},                                # shotgun binary
    %r{\(.*\)},                                      # generated code
    %r{shoulda/context\.rb$},                        # shoulda hacks
    %r{mocha/integration},                           # mocha hacks
    %r{test/unit},                                   # test unit hacks
    %r{rake_test_loader\.rb},                        # rake hacks
    %r{custom_require\.rb$},                         # rubygems require hacks
    %r{active_support},                              # active_support require hacks
    %r{/thor}                                        # thor require hacks
  ] unless defined?(PADRINO_IGNORE_CALLERS)

  ##
  # Add rubinius (and hopefully other VM implementations) ignore patterns ...
  #
  PADRINO_IGNORE_CALLERS.concat(RUBY_IGNORE_CALLERS) if defined?(RUBY_IGNORE_CALLERS)

  private
    ##
    # The filename for the file that is the direct caller (first caller).
    #
    # @return [String]
    #   The file the caller method exists in.
    #
    def self.first_caller
      caller_files.first
    end

    #
    # Like +Kernel#caller+ but excluding certain magic entries and without
    # line / method information; the resulting array contains filenames only.
    #
    # @return [Array<String>]
    #   The files of the calling methods.
    #
    def self.caller_files
      caller(1).
        map    { |line| line.split(/:(?=\d|in )/)[0,2] }.
        reject { |file,line| PADRINO_IGNORE_CALLERS.any? { |pattern| file =~ pattern } }.
        map    { |file,line| file }
    end
end # Padrino