1 files changed, 54 insertions, 2 deletions
diff --git a/test/ruby/test_case.rb b/test/ruby/test_case.rb
index 0067b74e2b..4a0f1bf78d 100644
--- a/test/ruby/test_case.rb
+++ b/test/ruby/test_case.rb
@@ -1,5 +1,5 @@
+# frozen_string_literal: false
 require 'test/unit'
-require_relative 'envutil.rb'
 
 class TestCase < Test::Unit::TestCase
   def test_case
@@ -81,7 +81,7 @@ class TestCase < Test::Unit::TestCase
     EOS
 
     assert_in_out_err(['-e', <<-EOS], '', %w[42], [])
-      class Fixnum; undef ===; def ===(o); p 42; true; end; end; case 1; when 1; end
+      class Integer; undef ===; def ===(o); p 42; true; end; end; case 1; when 1; end
     EOS
   end
 
@@ -102,5 +102,57 @@ class TestCase < Test::Unit::TestCase
     else
       assert(false)
     end
+    case 0
+    when 0r
+      assert(true)
+    else
+      assert(false)
+    end
+    case 0
+    when 0i
+      assert(true)
+    else
+      assert(false)
+    end
+  end
+
+  def test_method_missing
+    flag = false
+
+    case 1
+    when Class.new(BasicObject) { def method_missing(*) true end }.new
+      flag = true
+    end
+
+    assert(flag)
+  end
+
+  def test_nomethoderror
+    assert_raise(NoMethodError) {
+      case 1
+      when Class.new(BasicObject) { }.new
+      end
+    }
+  end
+
+  module NilEqq
+    refine NilClass do
+      def === other
+        false
+      end
+    end
+  end
+
+  class NilEqqClass
+    using NilEqq
+
+    def eqq(a)
+      case a; when nil then nil; else :not_nil; end
+    end
+  end
+
+
+  def test_deoptimize_nil
+    assert_equal :not_nil, NilEqqClass.new.eqq(nil)
   end
 end