1 files changed, 45 insertions, 1 deletions
diff --git a/spec/ruby/core/basicobject/equal_value_spec.rb b/spec/ruby/core/basicobject/equal_value_spec.rb
index 6c825513c1..15755a44a2 100644
--- a/spec/ruby/core/basicobject/equal_value_spec.rb
+++ b/spec/ruby/core/basicobject/equal_value_spec.rb
@@ -3,8 +3,52 @@ require_relative '../../shared/kernel/equal'
 
 describe "BasicObject#==" do
   it "is a public instance method" do
-    BasicObject.should have_public_instance_method(:==)
+    BasicObject.public_instance_methods(false).should.include?(:==)
   end
 
   it_behaves_like :object_equal, :==
+
+  it "is unaffected by overriding __id__" do
+    o1 = mock("object")
+    o2 = mock("object")
+    suppress_warning {
+      def o1.__id__; 10; end
+      def o2.__id__; 10; end
+    }
+    (o1 == o2).should == false
+  end
+
+  it "is unaffected by overriding object_id" do
+    o1 = mock("object")
+    o1.stub!(:object_id).and_return(10)
+    o2 = mock("object")
+    o2.stub!(:object_id).and_return(10)
+    (o1 == o2).should == false
+  end
+
+  it "is unaffected by overriding equal?" do
+    # different objects, overriding equal? to return true
+    o1 = mock("object")
+    o1.stub!(:equal?).and_return(true)
+    o2 = mock("object")
+    (o1 == o2).should == false
+
+    # same objects, overriding equal? to return false
+    o3 = mock("object")
+    o3.stub!(:equal?).and_return(false)
+    (o3 == o3).should == true
+  end
+
+  it "is unaffected by overriding eql?" do
+    # different objects, overriding eql? to return true
+    o1 = mock("object")
+    o1.stub!(:eql?).and_return(true)
+    o2 = mock("object")
+    (o1 == o2).should == false
+
+    # same objects, overriding eql? to return false
+    o3 = mock("object")
+    o3.stub!(:eql?).and_return(false)
+    (o3 == o3).should == true
+  end
 end