1 files changed, 11 insertions, 0 deletions
diff --git a/test/ruby/test_case.rb b/test/ruby/test_case.rb
index 41a22038a0..0123e7422f 100644
--- a/test/ruby/test_case.rb
+++ b/test/ruby/test_case.rb
@@ -1,4 +1,5 @@
 require 'test/unit'
+require 'envutil.rb'
 
 class TestCase < Test::Unit::TestCase
   def test_case
@@ -46,4 +47,14 @@ class TestCase < Test::Unit::TestCase
       assert(false)
     end
   end
+
+  def test_deoptimization
+    assert_in_out_err(['-e', <<-EOS], '', %w[42], [])
+      class Symbol; def ===(o); p 42; true; end; end; case :foo; when :foo; end
+    EOS
+
+    assert_in_out_err(['-e', <<-EOS], '', %w[42], [])
+      class Fixnum; def ===(o); p 42; true; end; end; case 1; when 1; end
+    EOS
+  end
 end