Try to fix flaky GC test

assert_not_nil could allocate objects which may trigger the major GC, so
don't run the assertions until the major GC has been ran.

1 files changed, 5 insertions, 2 deletions

diff --git a/test/ruby/test_gc.rb b/test/ruby/test_gc.rb
index 0f4a13211e..7650c68eca 100644
--- a/test/ruby/test_gc.rb
+++ b/test/ruby/test_gc.rb
@@ -262,9 +262,12 @@ class TestGc < Test::Unit::TestCase
       objects.append(100.times.map { '*' })
     end
 
-    assert_not_nil GC.latest_gc_info(:need_major_by)
+    need_major_by = GC.latest_gc_info(:need_major_by)
     GC.start(full_mark: false) # should be upgraded to major
-    assert_not_nil GC.latest_gc_info(:major_by)
+    major_by = GC.latest_gc_info(:major_by)
+
+    assert_not_nil(need_major_by)
+    assert_not_nil(major_by)
   end
 
   def test_stress_compile_send