From: cfis@... Date: 2019-06-11T08:00:36+00:00 Subject: [ruby-core:93039] [Ruby trunk Bug#15911] Missing TracePoint return event for ||= Issue #15911 has been reported by cfis (Charlie Savage). ---------------------------------------- Bug #15911: Missing TracePoint return event for ||= https://bugs.ruby-lang.org/issues/15911 * Author: cfis (Charlie Savage) * Status: Open * Priority: Normal * Assignee: * Target version: * ruby -v: * Backport: 2.4: UNKNOWN, 2.5: UNKNOWN, 2.6: UNKNOWN ---------------------------------------- While updating ruby-prof, I ran into an issue while profiling rails that caused ruby-prof to show an incorrect method invocation tree. This caused by the use of the ||= operator in minitest. Here is a small test case:

class Operators
  def self.should_be_called_by_test
  end

  def self.test
    self.a
    should_be_called_by_test
  end

  def self.b=(value)
  end

  def self.b
  end

  def self.a
    self.b ||= :random
  end
end

tp = TracePoint.new(:call, :c_call, :return, :c_return) do |event|
  p [event.event, event.method_id]
end

tp.enable do
  Operators.test
end

This is the result:

[:call, :test]
[:call, :a]
[:call, :b]
[:return, :b]
[:call, :b=]
[:return, :b=]
                                    <---------- Missing [:return, :a]
[:call, :should_be_called_by_test]
[:return, :should_be_called_by_test]
[:return, :test]

Notice there is a missing :return event for the :a method. ruby -v ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-darwin18] -- https://bugs.ruby-lang.org/ Unsubscribe: