Add nullptr support to scoped_ptr.

base/memory/scoped_ptr_unittest.cc

Index: base/memory/scoped_ptr_unittest.cc
diff --git a/base/memory/scoped_ptr_unittest.cc b/base/memory/scoped_ptr_unittest.cc
index e0c15484e0811c5c1e6aaf14c0a4d936be90521a..7a1e41ed1d8668b151c498dd511ba73c5c385ea4 100644
--- a/base/memory/scoped_ptr_unittest.cc
+++ b/base/memory/scoped_ptr_unittest.cc
@@ -406,6 +406,8 @@ TEST(ScopedPtrTest, PassBehavior) {
 
     // Should auto-destruct logger by end of scope.
     scoper.Pass();
+    // This differs from unique_ptr, as Pass() has side effects but std::move()
+    // does not.
     EXPECT_FALSE(scoper.get());
   }
   EXPECT_EQ(0, constructed);
@@ -602,3 +604,55 @@ TEST(ScopedPtrTest, OverloadedNewAndDelete) {
   EXPECT_EQ(1, OverloadedNewAndDelete::delete_count());
   EXPECT_EQ(1, OverloadedNewAndDelete::new_count());
 }
+
+scoped_ptr<int> NullIntReturn() {
+  return nullptr;
+}
+
+TEST(ScopedPtrTest, Nullptr) {
+  scoped_ptr<int> scoper1(nullptr);
+  scoped_ptr<int> scoper2(new int);
+  scoper2 = nullptr;
+  scoped_ptr<int> scoper3(NullIntReturn());
+  scoped_ptr<int> scoper4 = NullIntReturn();
+  EXPECT_EQ(nullptr, scoper1.get());
+  EXPECT_EQ(nullptr, scoper2.get());
+  EXPECT_EQ(nullptr, scoper3.get());
+  EXPECT_EQ(nullptr, scoper4.get());
+}
+
+scoped_ptr<int[]> NullIntArrayReturn() {
+  return nullptr;
+}
+
+TEST(ScopedPtrTest, NullptrArray) {
+  scoped_ptr<int[]> scoper1(nullptr);
+  scoped_ptr<int[]> scoper2(new int[3]);

[jamesr, 2014/09/27 20:30:36]

oh, that would explain it!  we do seem to have pretty good coverage above for
preserving deleters, but we might want to add more tests using rvalue semantics
when we get there.

+  scoper2 = nullptr;
+  scoped_ptr<int[]> scoper3(NullIntArrayReturn());
+  scoped_ptr<int[]> scoper4 = NullIntArrayReturn();
+  EXPECT_EQ(nullptr, scoper1.get());
+  EXPECT_EQ(nullptr, scoper2.get());
+  EXPECT_EQ(nullptr, scoper3.get());
+  EXPECT_EQ(nullptr, scoper4.get());
+}
+
+class Super {};
+class Sub : public Super {};
+
+scoped_ptr<Sub> SubClassReturn() {
+  return make_scoped_ptr(new Sub);
+}
+
+TEST(ScopedPtrTest, Conversion) {
+  scoped_ptr<Sub> sub1(new Sub);
+  scoped_ptr<Sub> sub2(new Sub);
+
+  // Upcast with Pass() works.
+  scoped_ptr<Super> super1 = sub1.Pass();
+  super1 = sub2.Pass();
+
+  // Upcast with an rvalue works.
+  scoped_ptr<Super> super2 = SubClassReturn();
+  super2 = SubClassReturn();
+}