[ruby-core:102859] [Ruby master Bug#11335] `ruby -r debug` catchpoint problem

Issue #11335 has been updated by ko1 (Koichi Sasada).

Status changed from Open to Closed

I'm rewriting lib/debug.rb with TracePoint.
And I close this ticket because it is too old.
Ruby 3.1 will have better debugger by default :)


----------------------------------------
Bug #11335: `ruby -r debug` catchpoint problem
https://bugs.ruby-lang.org/issues/11335#change-90917

* Author: sigsys (Math Ieu)
* Status: Closed
* Priority: Normal
* ruby -v: ruby 2.1.6p336 (2015-04-13 revision 50298) [i386-freebsd10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
With a `test-debug.rb` like this:

~~~
raise 'test'
~~~

And starting the debugger like this:

~~~
ruby -r debug test-debug.rb
~~~

By default, the catchpoint is `StandardError`, but it doesn't work:

~~~
test-debug.rb:1:raise 'test'
(rdb:1) catch
Catchpoint StandardError.
(rdb:1) c
test-debug.rb:1:in `<main>': test (RuntimeError)
~~~

And the debugger exits without catching the exception.

But, by setting the catchpoint to `NilClass` (or one of its ancestors), then it works:

~~~
test-debug.rb:1:raise "test"
(rdb:1) catch NilClass
Set catchpoint NilClass.
(rdb:1) c
test-debug.rb:1: `' (NilClass)
        from test-debug.rb:1:in `<main>'
test-debug.rb:1:raise "test"
~~~

And the debugger does not exit and allows further debugging.

By looking at `lib/debug.rb`, it looks like that the `set_trace_func` callback it sets assumes that `$!` will be set to the exception to be raised when a `'raise'` event occurs.  But it is not the case, `$!` seems to always be `nil`.




-- 
https://bugs.ruby-lang.org/

Unsubscribe: <mailto:[e-mail]?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>