3 files changed, 37 insertions, 11 deletions
diff --git a/tool/lib/gc_checker.rb b/tool/lib/gc_checker.rb
new file mode 100644
index 0000000000..719da8cac0
--- /dev/null
+++ b/tool/lib/gc_checker.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module GCDisabledChecker
+  def before_setup
+    if @__gc_disabled__ = GC.enable # return true if GC is disabled
+      GC.disable
+    end
+
+    super
+  end
+
+  def after_teardown
+    super
+
+    disabled = GC.enable
+    GC.disable if @__gc_disabled__
+
+    if @__gc_disabled__ != disabled
+      label = {
+        true => 'disabled',
+        false => 'enabled',
+      }
+      raise "GC was #{label[@__gc_disabled__]}, but is #{label[disabled]} after the test."
+    end
+  end
+end
+
+module GCCompactChecker
+  def after_teardown
+    super
+    GC.compact
+  end
+end
+
+Test::Unit::TestCase.include GCDisabledChecker
+Test::Unit::TestCase.include GCCompactChecker if ENV['RUBY_TEST_GC_COMPACT']
diff --git a/tool/lib/gc_compact_checker.rb b/tool/lib/gc_compact_checker.rb
deleted file mode 100644
index a6ef3d3ce8..0000000000
--- a/tool/lib/gc_compact_checker.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-# frozen_string_literal: true
-
-module GCCompactChecker
-  def after_teardown
-    super
-    GC.compact
-  end
-end
-
-Test::Unit::TestCase.include GCCompactChecker if ENV['RUBY_TEST_GC_COMPACT']
diff --git a/tool/lib/test/unit/parallel.rb b/tool/lib/test/unit/parallel.rb
index ccaf1a913a..0807b3916b 100644
--- a/tool/lib/test/unit/parallel.rb
+++ b/tool/lib/test/unit/parallel.rb
@@ -6,7 +6,7 @@ require "profile_test_all" if ENV.key?('RUBY_TEST_ALL_PROFILE')
 require "tracepointchecker"
 require "zombie_hunter"
 require "iseq_loader_checker"
-require "gc_compact_checker"
+require "gc_checker"
 
 module Test
   module Unit