Add tracepoint.rb to 2.0.0

[trans]

Hi, last night I finally reworked my the original TracePoint library to be compatible with Ruby 2.0's new rendition (as I mention in issue #65).

It's not quite finished. Unfortunately I don't have the time to put the final polish on, but it is very close, and it is functional. I left a few TODOs in the code about what's left to work out. There isn't much, the primary thing is the proper definitions of raised_exception and return_value. Those are new, and I am not sure how they are (or if they even can be) defined. HTH.

[trans]

Oh, I should mention one thing. In the Ruby library you can select which event you want to monitor. I don't think that's possible in this pure Ruby version. So it just pretends to do so, but is actually monitoring all events.

[marcandre]

I haven't had the time to check the API for tracepoint. Can you raise NotImplementedError for the cases that are not handled?

[trans]

There you go.

[marcandre]

I've introduced actual automated tests for backports. Could you fix https://travis-ci.org/marcandre/backports/jobs/5226693 ?

Also, could you copy MRI's tests and adapt them? There might be some {new_syntax: 1} to change to {old_syntax => 2}, and some tests might be ok to fail...

Finally, please squash the commits, unless they are independent.

BTW, I'm almost done with a huge refactoring making each backport mostly independent (in the split branch currently), so the last two backports will be simple requires.

[trans]

I looked at the test failure and I think something is wrong with the "guard" --I don't see anything wrong with the code. Maybe it is confused b/c it is an if within a case? But maybe I missed something. Have a look and see what you think.

I removed the docs, squashed all the commits and forced pushed, so that's done. But it does not include any test from MRI b/c I could not find it. Do you know where it is?

[marcandre]

Cool.

The test will fail if including your file issues warnings in verbose mode. The indentation is screwed up because you have tabs in your file...

MRI tests are in test/ruby/test_settracefunc.rb

[trans]

Ah okay. I will do the rest in the morning then. Thanks.

[trans]

So I ported over the tests, and as you expected there were some discrepancies due to new 2.0 features like keyword arguments. I adjusted for those with the exception of caller_locations. I thought that might get implemented for backports so I left it.

There are a few other issues remaining:

1. raised_exception and return_value raise NotImplementedError (as mentioned previously).
2. set_trace_func should raise a SecurityError if $SAFE=4. That's outside the scope of TracePoint itself, maybe you want to patch set_trace_func itself for that?
3. I do not think Ruby<2.0 supports b_call and b_return events. Is that right?
4. I do not think Ruby<2.0 supports thread_begin and thread_end events. Is that right?
5. Lastly, there is a minor discrepancy in inspect, where it does not return #<TracePoint:enabled> b/c it has a current line event.

I will rebase the new changes into a single commit after we address these.

[trans]

It's too bad this never made it in. There is no way for it to be 100% compatible with Ruby's implementation b/c some things simply aren't possible in pure Ruby. But it is something like 98% the same.

[marcandre]

Mmm, looks like I completely forgot about this.
So as far as you're concerned, this is as complete as can be, then?

[marcandre]

BTW, I've done caller_locations, just have not pushed it yet.

[trans]

I believe so, yes.

[marcandre]

Ok, I'll have to review the code, squash the commits, and figure out why the build does not pass...