irb-hack-no-tf.rb

# How to use.
# $ irb
# >> load 'irb-hack-no-tf.rb' # Substitute file path. NOTE: 'load', not 'require'
# >> # work, work, work... look at CLASSES, METHODS and MODULES
require 'irb'

$IRBHACK_DEBUG = true
# irb-hack.rb without threadframe and trace modules. However since
# there is still a bug in the way Ruby handles c-call events (it calls the
# hook before pushing the the frame), this doesn't catch "define-method"
# calls properly.
CLASSES = {}
METHODS = {}
MODULES = {}
CHECK_METHODS = %w(define_method method_added singleton_method_added CLASS)

def capture_hook(event, file, line, id, binding, classname)
  return unless CHECK_METHODS.member?(id.to_s)

  # Work around what is probably a bug in the way classname
  # is set inside the Ruby 1.9 callback hook.
  klass = eval('self.to_s', binding)  

  p [event, file, id, klass, classname] if $IRBHACK_DEBUG

  lines = $irb_stmts.split(/\n/)
  return unless lines.size + $irb_firstline >= line
  loc = line

  first_line = lines[loc - $irb_firstline]
  puts "checking #{first_line}..." if $IRBHACK_DEBUG
  if 'class' == event 
    if first_line =~ /^\s*class\s+(\S+)/
      puts "adding #{klass}" if $IRBHACK_DEBUG
      CLASSES[klass] = $irb_stmts 
      return
    end
  elsif first_line =~ /^\s*def\s+([^(; \t\n]+)(:?[ \t\n(;])?/
    puts "adding #{klass}::#{$1}" if $IRBHACK_DEBUG
    METHODS["#{klass}::#{$1}"] = $irb_stmts 
  end

  MODULES[$1] = $irb_stmts if $irb_stmts =~ /^\s*module\s+(\S+)\s+/
end

# Monkeypatch to save the current IRB statement to be run.
# Possibly not needed.
class IRB::Context
  alias original_evaluate evaluate
  def evaluate(line, line_no)
    $irb_stmts = line
    $irb_firstline = line_no
    original_evaluate(line, line_no)
  end
end

workspace = IRB::WorkSpace.new(binding)
irb = IRB::Irb.new(workspace)
set_trace_func(method(:capture_hook).to_proc)
irb.eval_input

irb-hack.rb

# How to use.
# $ irb
# >> load 'irb-hack.rb' # Substitute file path. NOTE: 'load', not 'require
# >> # work, work, work... look at CLASSES, METHODS and MODULES

require 'irb'
require 'trace'

include Trace
CLASSES = {}
METHODS = {}
MODULES = {}
CHECK_METHODS = %w(define_method method_added singleton_method_added CLASS)

def capture_hook(event, frame, arg=nil)
  return unless CHECK_METHODS.member?(frame.method)

  klass = eval('self.to_s', frame.binding)
  lines = $irb_stmts.split(/\n/)
  return unless frame.source_container[0] == 'string' && 
    lines.size + $irb_firstline >= frame.source_location[0]
  loc = frame.source_location[0]

  first_line = lines[loc - $irb_firstline]
  puts "checking #{first_line}..." if $IRBHACK_DEBUG
  if 'class' == event 
    if first_line =~ /^\s*class\s+(\S+)/
      puts "adding #{klass}" if $IRBHACK_DEBUG
      CLASSES[klass] = $irb_stmts 
      return
    end
  elsif first_line =~ /^\s*def\s+([^(; \t\n]+)(:?[ \t\n(;])?/
    puts "adding #{klass}::#{$1}" if $IRBHACK_DEBUG
    METHODS["#{klass}::#{$1}"] = $irb_stmts 
  end

  MODULES[$1] = $irb_stmts if $irb_stmts =~ /^\s*module\s+(\S+)\s+/
end

# Monkeypatch to save the current IRB statement to be run.
# Possibly not needed.
class IRB::Context
  alias original_evaluate evaluate
  def evaluate(line, line_no)
    $irb_stmts = line
    $irb_firstline = line_no
    original_evaluate(line, line_no)
  end
end

workspace = IRB::WorkSpace.new(binding)
irb = IRB::Irb.new(workspace)
trace_filter = Trace::Filter.new
trace_filter.add_trace_func(method(:capture_hook).to_proc,
                            C_CALL_EVENT_MASK | CLASS_EVENT_MASK)
irb.eval_input

Hey, Rocky. Ages ago (at some conf) you asked me to give a look at this Gist - and for whatever reason, I lost my note and found it again after years. ;)

Is this hack still relevant for the latest Rubies?

I think so for MRI YARV. rubinius doesn't implement trace hooks but JRuby does. So why not try it and get back to me in a year or so if it doesn't work?

Will do! This should take even less than a year.