Enable boolean testing of scoped_refptr<T>.

base/memory/ref_counted_unittest.cc

Index: base/memory/ref_counted_unittest.cc
diff --git a/base/memory/ref_counted_unittest.cc b/base/memory/ref_counted_unittest.cc
index 7e73bde1155db44e11eb2bdf071091782a648ce6..f75cd38f19c86d530237200e37792a2cde9480eb 100644
--- a/base/memory/ref_counted_unittest.cc
+++ b/base/memory/ref_counted_unittest.cc
@@ -10,9 +10,19 @@
 namespace {
 
 class SelfAssign : public base::RefCounted<SelfAssign> {
+ protected:
+  virtual ~SelfAssign() {}
+
+ private:
   friend class base::RefCounted<SelfAssign>;
+};
+
+class Derived : public SelfAssign {
+ protected:
+  ~Derived() override {}
 
-  ~SelfAssign() {}
+ private:
+  friend class base::RefCounted<Derived>;
 };
 
 class CheckDerivedMemberAccess : public scoped_refptr<SelfAssign> {
@@ -72,3 +82,34 @@ TEST(RefCountedUnitTest, ScopedRefPtrToOpaque) {
   base::TestOpaqueRefCounted(p);
   base::TestOpaqueRefCounted(q);
 }
+
+TEST(RefCountedUnitTest, BooleanTesting) {
+  scoped_refptr<SelfAssign> p;
+  EXPECT_FALSE(p);
+  p = new SelfAssign;
+  EXPECT_TRUE(p);
+}
+
+TEST(RefCountedUnitTest, Equality) {
+  scoped_refptr<SelfAssign> p1(new SelfAssign);
+  scoped_refptr<SelfAssign> p2(new SelfAssign);
+
+  EXPECT_EQ(p1, p1);
+  EXPECT_EQ(p2, p2);
+
+  EXPECT_NE(p1, p2);

[dcheng, 2014/11/25 08:44:36]

This is primarily to ensure that we're not inadvertently converting both sides
to a Testable before doing the comparison.

+  EXPECT_NE(p2, p1);
+}
+
+TEST(RefCountedUnitTest, ConvertibleEquality) {

[dcheng, 2014/11/25 08:44:36]

shared_ptr allows comparisons between convertible types
(http://en.cppreference.com/w/cpp/memory/shared_ptr/operator_cmp), so I opted to
test that behavior explicitly here.

+  scoped_refptr<Derived> p1(new Derived);
+  scoped_refptr<SelfAssign> p2;
+
+  EXPECT_NE(p1, p2);
+  EXPECT_NE(p2, p1);
+
+  p2 = p1;
+
+  EXPECT_EQ(p1, p2);
+  EXPECT_EQ(p2, p1);
+}