tracing method calls

tracing.rb

level = 0

call_trace = TracePoint.new(:call) do |event|
  indent = ' ' * level
  Rails.logger.info("#{indent}#{level} : #{event.event} " +
                    "#{event.defined_class}\##{event.method_id}   " +
                    "@ #{event.path}:#{event.lineno}")
  level += 1
end

return_trace = TracePoint.new(:return) do |event|
  level -= 1
  indent = ' ' * level
  Rails.logger.info("#{indent}#{level} : #{event.event} " +
                    "#{event.defined_class}\##{event.method_id} " +
                    "@ #{event.path}:#{event.lineno}")
end

call_trace.enable
return_trace.enable

set_trace_func proc { |event, file, line, method_id, binding, classname|
  case event
  when 'call'
    indent = ' ' * level
    Rails.logger.info("#{indent}#{level}: #{event} " +
                      "#{classname}\##{method_id}   " +
                      "\n#{indent}    #{file}:#{line}")
    level += 1

    set_trace_func nil if level > 60
  when 'return'
    level -= 1
    indent = ' ' * level
    Rails.logger.info("#{indent}#{level}: #{event} " +
                      "#{classname}\##{method_id}   " +
                      "\n#{indent}    #{file}:#{line}")
  end
}