1 files changed, 7 insertions, 0 deletions
diff --git a/spec/ruby/core/string/include_spec.rb b/spec/ruby/core/string/include_spec.rb
index 8da12a9862..d7780de602 100644
--- a/spec/ruby/core/string/include_spec.rb
+++ b/spec/ruby/core/string/include_spec.rb
@@ -25,4 +25,11 @@ describe "String#include? with String" do
     lambda { "hello".include?('h'.ord)  }.should raise_error(TypeError)
     lambda { "hello".include?(mock('x')) }.should raise_error(TypeError)
   end
+
+  it "raises an Encoding::CompatibilityError if the encodings are incompatible" do
+    pat = "ア".encode Encoding::EUC_JP
+    lambda do
+      "あれ".include?(pat)
+    end.should raise_error(Encoding::CompatibilityError)
+  end
 end