test: Follow-up fix for #8916

`test_thread_trace` is also flaky due to the same reason as #8916.

https://rubyci.s3.amazonaws.com/centos7/ruby-master/log/20231114T213002Z.fail.html.gz
https://rubyci.s3.amazonaws.com/wsl2/ruby-master/log/20231114T090003Z.fail.html.gz

1 files changed, 3 insertions, 3 deletions

diff --git a/test/ruby/test_settracefunc.rb b/test/ruby/test_settracefunc.rb
index 03ff522efb..8647723ed3 100644
--- a/test/ruby/test_settracefunc.rb
+++ b/test/ruby/test_settracefunc.rb
@@ -358,18 +358,18 @@ class TestSetTraceFunc < Test::Unit::TestCase
 
   def test_thread_trace
     events = {:set => [], :add => []}
+    name = "#{self.class}\##{__method__}"
     prc = Proc.new { |event, file, lineno, mid, binding, klass|
-      events[:set] << [event, lineno, mid, klass, :set]
+      events[:set] << [event, lineno, mid, klass, :set] if file == name
     }
     prc = prc # suppress warning
     prc2 = Proc.new { |event, file, lineno, mid, binding, klass|
-      events[:add] << [event, lineno, mid, klass, :add]
+      events[:add] << [event, lineno, mid, klass, :add] if file == name
     }
     prc2 = prc2 # suppress warning
 
     th = Thread.new do
       th = Thread.current
-      name = "#{self.class}\##{__method__}"
       eval <<-EOF.gsub(/^.*?: /, ""), nil, name
        1: th.set_trace_func(prc)
        2: th.add_trace_func(prc2)