2 files changed, 37 insertions, 2 deletions
diff --git a/test/ruby/test_box.rb b/test/ruby/test_box.rb
index a39979109f..a425c5eb7d 100644
--- a/test/ruby/test_box.rb
+++ b/test/ruby/test_box.rb
@@ -1180,4 +1180,40 @@ class TestBox < Test::Unit::TestCase
       assert_equal :box2, box2.eval("Class.new { include Math }.new.box2_test")
     end;
   end
+
+  def test_method_invalidation_between_boxes_1
+    assert_separately([ENV_ENABLE_BOX], __FILE__, __LINE__, "#{<<~"begin;"}\n#{<<~'end;'}", ignore_stderr: true)
+    begin;
+      b = Ruby::Box.new
+      b.eval(<<~'RUBY')
+      Module.prepend(Module.new)
+        class C; end
+        class D < C; end
+        def C.===(x) = true
+      RUBY
+
+      assert String === "x"
+      assert b # to prevent GCing b
+    end;
+  end
+
+  def test_method_invalidation_between_boxes_2
+    assert_separately([ENV_ENABLE_BOX], __FILE__, __LINE__, "#{<<~"begin;"}\n#{<<~'end;'}", ignore_stderr: true)
+    begin;
+      PrepM = Module.new
+      Module.prepend(PrepM)
+      Module.new.include?(Module.new)
+
+      b = Ruby::Box.new
+      b.eval(<<~'RUBY')
+        Module.class_eval { def _test_method; end }
+
+        class C; end
+        class D < C; end
+        def C.include?(x) = true
+      RUBY
+
+      Module.new.include?(Module.new)
+    end;
+  end
 end
diff --git a/test/ruby/test_string.rb b/test/ruby/test_string.rb
index 67a19e1ae0..aedfc93e5d 100644
--- a/test/ruby/test_string.rb
+++ b/test/ruby/test_string.rb
@@ -851,7 +851,6 @@ CODE
     assert_equal(S("\u{AB}"), S('"\\u00AB"').undump)
     assert_equal(S("\u{ABC}"), S('"\\u0ABC"').undump)
     assert_equal(S("\uABCD"), S('"\\uABCD"').undump)
-    assert_equal(S("\uABCD"), S('"\\uABCD"').undump)
     assert_equal(S("\u{ABCDE}"), S('"\\u{ABCDE}"').undump)
     assert_equal(S("\u{10ABCD}"), S('"\\u{10ABCD}"').undump)
     assert_equal(S("\u{ABCDE 10ABCD}"), S('"\\u{ABCDE 10ABCD}"').undump)
@@ -2629,7 +2628,7 @@ CODE
   end
 
   def test_upcase
-    assert_equal(S("HELLO"), S("hello").upcase)
+    assert_equal(S("HELLO"), S("helLO").upcase)
     assert_equal(S("HELLO"), S("hello").upcase)
     assert_equal(S("HELLO"), S("HELLO").upcase)
     assert_equal(S("ABC HELLO 123"), S("abc HELLO 123").upcase)