a.rb

TracePoint.trace { |tp| puts tp.inspect }        # 1

class Foo
  def to_ary
    proc { [1,2] }.call
  end
end


proc { |a,| }.call(Foo.new)

gistfile1.txt

system ~/work/jruby master * 1121% mri26 ../snippets/tracenpoint2.rb 
#<TracePoint:c_return `trace'@../snippets/tracenpoint2.rb:1>
#<TracePoint:line@../snippets/tracenpoint2.rb:3>
#<TracePoint:c_call `inherited'@../snippets/tracenpoint2.rb:3>
#<TracePoint:c_return `inherited'@../snippets/tracenpoint2.rb:3>
#<TracePoint:class@../snippets/tracenpoint2.rb:3>
#<TracePoint:line@../snippets/tracenpoint2.rb:4>
#<TracePoint:c_call `method_added'@../snippets/tracenpoint2.rb:4>
#<TracePoint:c_return `method_added'@../snippets/tracenpoint2.rb:4>
#<TracePoint:end@../snippets/tracenpoint2.rb:7>
#<TracePoint:line@../snippets/tracenpoint2.rb:10>
#<TracePoint:c_call `proc'@../snippets/tracenpoint2.rb:10>
#<TracePoint:c_return `proc'@../snippets/tracenpoint2.rb:10>
#<TracePoint:c_call `new'@../snippets/tracenpoint2.rb:10>
#<TracePoint:c_call `initialize'@../snippets/tracenpoint2.rb:10>
#<TracePoint:c_return `initialize'@../snippets/tracenpoint2.rb:10>
#<TracePoint:c_return `new'@../snippets/tracenpoint2.rb:10>
#<TracePoint:call `to_ary'@../snippets/tracenpoint2.rb:4>
#<TracePoint:line@../snippets/tracenpoint2.rb:5 in `to_ary'>
#<TracePoint:c_call `proc'@../snippets/tracenpoint2.rb:5>
#<TracePoint:c_return `proc'@../snippets/tracenpoint2.rb:5>
#<TracePoint:b_call@../snippets/tracenpoint2.rb:5>
#<TracePoint:line@../snippets/tracenpoint2.rb:5 in `to_ary'>
#<TracePoint:b_return@../snippets/tracenpoint2.rb:5>
#<TracePoint:return `to_ary'@../snippets/tracenpoint2.rb:6>
#<TracePoint:b_call@../snippets/tracenpoint2.rb:10>
#<TracePoint:b_return@../snippets/tracenpoint2.rb:10>