Add more specs for singleton_method_added

Author: eregon

spec/ruby/core/basicobject/singleton_method_added_spec.rb

@@ -83,4 +83,63 @@ class << self
     end
     ScratchPad.recorded.should == [:singleton_method_added, :new_method_with_define_method]
   end
+
+  describe "when singleton_method_added is undefined" do
+    it "raises NoMethodError for a metaclass" do
+      class BasicObjectSpecs::NoSingletonMethodAdded
+        class << self
+          undef_method :singleton_method_added
+        end
+
+        -> {
+          def self.foo
+          end
+        }.should raise_error(NoMethodError, /undefined method `singleton_method_added' for/)
+      end
+    end
+
+    it "raises NoMethodError for a singleton instance" do
+      object = Object.new
+      class << object
+        undef_method :singleton_method_added
+
+        -> {
+          def foo
+          end
+        }.should raise_error(NoMethodError, /undefined method `singleton_method_added' for #<Object:/)
+
+        -> {
+          define_method(:bar) {}
+        }.should raise_error(NoMethodError, /undefined method `singleton_method_added' for #<Object:/)
+      end
+
+      -> {
+        object.define_singleton_method(:baz) {}
+      }.should raise_error(NoMethodError, /undefined method `singleton_method_added' for #<Object:/)
+    end
+
+    it "calls #method_missing" do
+      ScratchPad.record []
+      object = Object.new
+      class << object
+        def method_missing(*args)
+          ScratchPad << args
+        end
+
+        undef_method :singleton_method_added
+
+        def foo
+        end
+
+        define_method(:bar) {}
+      end
+      object.define_singleton_method(:baz) {}
+
+      ScratchPad.recorded.should == [
+        [:singleton_method_added, :foo],
+        [:singleton_method_added, :bar],
+        [:singleton_method_added, :baz],
+      ]
+    end
+  end
 end