From: SASADA Koichi <ko1@...>
Date: 2014-01-07T18:01:38+09:00
Subject: [ruby-core:59623] Re: [ruby-trunk - Bug #9321] rb_mod_const_missing does not generate a c-return event

(2014/01/03 3:19), drkaes (Stefan Kaes) wrote:
> @ko1: Why do you think the second patch creates a performance problem?
> 
> Module#const_missing is an exceptional case. Am I missing something?

Sorry for my misunderstanding.

Let me clarify the spec.

###
n = 0
TracePoint.new(){|tp|
  next if tp.event == :line
  case tp.event.to_s
  when /call/
    puts "#{' ' * 2 * n}#{tp.inspect}"
    n+=1
  when /return/
    n-=1 if n>0
    puts "#{' ' * 2 * n}#{tp.inspect}"
  else
    puts "#{' ' * 2 * n}#{tp.inspect}"
  end
}.enable

def f
  Object::XYZZY #=> const_missing
end

f
__END__
#=>

current behavior:

#<TracePoint:c_return `enable'@test.rb:15>
#<TracePoint:c_call `method_added'@test.rb:17>
#<TracePoint:c_return `method_added'@test.rb:17>
#<TracePoint:call `f'@test.rb:17>
  #<TracePoint:c_call `const_missing'@test.rb:18>
    #<TracePoint:c_call `initialize'@test.rb:18>
      #<TracePoint:c_call `initialize'@test.rb:18>
      #<TracePoint:c_return `initialize'@test.rb:18>
    #<TracePoint:c_return `initialize'@test.rb:18>
    #<TracePoint:c_call `exception'@test.rb:18>
    #<TracePoint:c_return `exception'@test.rb:18>
    #<TracePoint:c_call `backtrace'@test.rb:18>
    #<TracePoint:c_return `backtrace'@test.rb:18>
    #<TracePoint:raise@test.rb:18>
  #<TracePoint:return `f'@test.rb:18>

expected behavior:

#<TracePoint:c_return `enable'@test.rb:15>
#<TracePoint:c_call `method_added'@test.rb:17>
#<TracePoint:c_return `method_added'@test.rb:17>
#<TracePoint:call `f'@test.rb:17>
  #<TracePoint:c_call `const_missing'@test.rb:18>
  #<TracePoint:c_return `const_missing'@test.rb:18> <-- NEW!
  #<TracePoint:c_call `initialize'@test.rb:18>
    #<TracePoint:c_call `initialize'@test.rb:18>
    #<TracePoint:c_return `initialize'@test.rb:18>
  #<TracePoint:c_return `initialize'@test.rb:18>
  #<TracePoint:c_call `exception'@test.rb:18>
  #<TracePoint:c_return `exception'@test.rb:18>
  #<TracePoint:c_call `backtrace'@test.rb:18>
  #<TracePoint:c_return `backtrace'@test.rb:18>
  #<TracePoint:raise@test.rb:18>
#<TracePoint:return `f'@test.rb:18>


is it right?

This behavior is similar to "raise" behavior.

-- 
// SASADA Koichi at atdot dot net