Issue #21272 has been updated by Eregon (Benoit Daloze). cfis (Charlie Savage) wrote in #note-2:
This is a difference in Ruby 4.0. Previous versions of Ruby sent out a Class.new event.
No they did not as far as I can see. Even Ruby 2.0.0 does not emit a `:class` tracepoint for `Class.new`: ``` $ ruby -ve 'TracePoint.trace(:class) { puts "class tp" }; p 1; class Foo; end; p 2; Class.new {}' ruby 2.0.0p648 (2015-12-16 revision 53162) [x86_64-linux] 1 class tp 2 $ ruby -ve 'TracePoint.trace(:class) { puts "class tp" }; p 1; class Foo; end; p 2; Class.new {}' ruby 4.0.1 (2026-01-13 revision e04267a14b) +PRISM [x86_64-linux] 1 class tp 2 ``` ---------------------------------------- Bug #21272: Class.new doesn't trigger :class TracePoint https://bugs.ruby-lang.org/issues/21272#change-116311 * Author: st0012 (Stan Lo) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- According to the official [documentation](https://docs.ruby-lang.org/en/master/TracePoint.html#class-TracePoint-label-...):
To filter what is traced, you can pass any of the following as events:
:class Start a class or module definition.
I'd expect `:class` events to be triggered when new classes are defined via `Class.new` as well, but currently that's not the case. Should we either support `Class.new`, or clarify the behaviour in documentation? ### Reproduction ```rb TracePoint.trace(:class) do |tp| puts "Class created at line: #{tp.lineno}" end class Foo; end # Triggers the tracepoint Baz = Class.new # Doesn't trigger the tracepoint # ruby test.rb # Class created at line: 5 ``` -- https://bugs.ruby-lang.org/