Remove multiple inheritance from "unintesting call" mock classes.refs/pull/1557/head

Internal CL 156157936, which was published in commit
fe402c27790ff1cc9a7e17c5d0aea4ebe7fd8a71, introduced undefined behavior
by casting a base class (internal::{Naggy,Nice,Strict}Base<MockClass>,
using the curiously recurring template pattern) pointer to a derived
class ({Naggy,Nice,Strict}Mock<MockClass>), in the base class'
constructor. At that point, the object isn't guaranteed to have taken on
the shape of the derived class, and casting is undefined behavior.

The undefined behavior was caught by Chrome's CFI build bot [1], and
prevents rolling googletest past that commit / CL.

This commit simplifies the {Naggy,Nice,Strict}Mock class hierarchy in
a way that removes the undefined behavior.

[1] https://www.chromium.org/developers/testing/control-flow-integrity

1 files changed, 174 insertions, 158 deletions

diff --git a/googlemock/include/gmock/gmock-generated-nice-strict.h b/googlemock/include/gmock/gmock-generated-nice-strict.h
index af71fbd..5e1386b 100644
--- a/googlemock/include/gmock/gmock-generated-nice-strict.h
+++ b/googlemock/include/gmock/gmock-generated-nice-strict.h
@@ -71,329 +71,345 @@
 
 namespace testing {
 
-namespace internal {
-
-// NiceMockBase serves as a mix-in to establish the "uninteresting call"
-// behavior for NiceMock on construction. It accomplishes this via CRTP to get
-// access to the derived MockClass.
-template <class MockClass>
-class NiceMockBase {
- protected:
-  NiceMockBase();
-
-  ~NiceMockBase();
-};
-
-}  // namespace internal
-
 template <class MockClass>
-class NiceMock : public MockClass, public internal::NiceMockBase<MockClass> {
+class NiceMock : public MockClass {
  public:
-  NiceMock() : MockClass() {}
+  NiceMock() : MockClass() {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
 #if GTEST_LANG_CXX11
-  // Ideally, we would inherit base class's constructors through a using
-  // declaration, which would preserve their visibility. However, many existing
-  // tests rely on the fact that current implementation reexports protected
-  // constructors as public. These tests would need to be cleaned up first.
-
   // Single argument constructor is special-cased so that it can be
   // made explicit.
   template <typename A>
-  explicit NiceMock(A&& arg) : MockClass(std::forward<A>(arg)) {}
+  explicit NiceMock(A&& arg) : MockClass(std::forward<A>(arg)) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename... An>
   NiceMock(A1&& arg1, A2&& arg2, An&&... args)
       : MockClass(std::forward<A1>(arg1), std::forward<A2>(arg2),
-                  std::forward<An>(args)...) {}
+                  std::forward<An>(args)...) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 #else
   // C++98 doesn't have variadic templates, so we have to define one
   // for each arity.
   template <typename A1>
-  explicit NiceMock(const A1& a1) : MockClass(a1) {}
+  explicit NiceMock(const A1& a1) : MockClass(a1) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
   template <typename A1, typename A2>
-  NiceMock(const A1& a1, const A2& a2) : MockClass(a1, a2) {}
+  NiceMock(const A1& a1, const A2& a2) : MockClass(a1, a2) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3>
-  NiceMock(const A1& a1, const A2& a2, const A3& a3) : MockClass(a1, a2, a3) {}
+  NiceMock(const A1& a1, const A2& a2, const A3& a3) : MockClass(a1, a2, a3) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4>
   NiceMock(const A1& a1, const A2& a2, const A3& a3,
-      const A4& a4) : MockClass(a1, a2, a3, a4) {}
+      const A4& a4) : MockClass(a1, a2, a3, a4) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5>
   NiceMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
-      const A5& a5) : MockClass(a1, a2, a3, a4, a5) {}
+      const A5& a5) : MockClass(a1, a2, a3, a4, a5) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6>
   NiceMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
-      const A5& a5, const A6& a6) : MockClass(a1, a2, a3, a4, a5, a6) {}
+      const A5& a5, const A6& a6) : MockClass(a1, a2, a3, a4, a5, a6) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7>
   NiceMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7) : MockClass(a1, a2, a3, a4, a5,
-      a6, a7) {}
+      a6, a7) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8>
   NiceMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8) : MockClass(a1,
-      a2, a3, a4, a5, a6, a7, a8) {}
+      a2, a3, a4, a5, a6, a7, a8) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8, typename A9>
   NiceMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8,
-      const A9& a9) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9) {}
+      const A9& a9) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8, typename A9, typename A10>
   NiceMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8, const A9& a9,
-      const A10& a10) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {}
+      const A10& a10) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {
+    ::testing::Mock::AllowUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
 #endif  // GTEST_LANG_CXX11
 
+  ~NiceMock() {
+    ::testing::Mock::UnregisterCallReaction(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
+
  private:
   GTEST_DISALLOW_COPY_AND_ASSIGN_(NiceMock);
 };
 
-namespace internal {
-
-template <typename MockClass>
-NiceMockBase<MockClass>::NiceMockBase() {
-  ::testing::Mock::AllowUninterestingCalls(
-      internal::ImplicitCast_<MockClass*>(
-          static_cast<NiceMock<MockClass> *>(this)));
-}
-
-template <typename MockClass>
-NiceMockBase<MockClass>::~NiceMockBase() {
-  ::testing::Mock::UnregisterCallReaction(
-      internal::ImplicitCast_<MockClass*>(
-          static_cast<NiceMock<MockClass>*>(this)));
-}
-
-}  // namespace internal
-
-namespace internal {
-
-// NaggyMockBase serves as a mix-in to establish the "uninteresting call"
-// behavior for NaggyMock on construction. It accomplishes this via CRTP to get
-// access to the derived MockClass.
-template <class MockClass>
-class NaggyMockBase {
- protected:
-  NaggyMockBase();
-
-  ~NaggyMockBase();
-};
-
-}  // namespace internal
-
 template <class MockClass>
-class NaggyMock : public MockClass, public internal::NaggyMockBase<MockClass> {
+class NaggyMock : public MockClass {
  public:
-  NaggyMock() : MockClass() {}
+  NaggyMock() : MockClass() {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
 #if GTEST_LANG_CXX11
-  // Ideally, we would inherit base class's constructors through a using
-  // declaration, which would preserve their visibility. However, many existing
-  // tests rely on the fact that current implementation reexports protected
-  // constructors as public. These tests would need to be cleaned up first.
-
   // Single argument constructor is special-cased so that it can be
   // made explicit.
   template <typename A>
-  explicit NaggyMock(A&& arg) : MockClass(std::forward<A>(arg)) {}
+  explicit NaggyMock(A&& arg) : MockClass(std::forward<A>(arg)) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename... An>
   NaggyMock(A1&& arg1, A2&& arg2, An&&... args)
       : MockClass(std::forward<A1>(arg1), std::forward<A2>(arg2),
-                  std::forward<An>(args)...) {}
+                  std::forward<An>(args)...) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 #else
   // C++98 doesn't have variadic templates, so we have to define one
   // for each arity.
   template <typename A1>
-  explicit NaggyMock(const A1& a1) : MockClass(a1) {}
+  explicit NaggyMock(const A1& a1) : MockClass(a1) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
   template <typename A1, typename A2>
-  NaggyMock(const A1& a1, const A2& a2) : MockClass(a1, a2) {}
+  NaggyMock(const A1& a1, const A2& a2) : MockClass(a1, a2) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3>
-  NaggyMock(const A1& a1, const A2& a2, const A3& a3) : MockClass(a1, a2, a3) {}
+  NaggyMock(const A1& a1, const A2& a2, const A3& a3) : MockClass(a1, a2, a3) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3,
-      const A4& a4) : MockClass(a1, a2, a3, a4) {}
+      const A4& a4) : MockClass(a1, a2, a3, a4) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
-      const A5& a5) : MockClass(a1, a2, a3, a4, a5) {}
+      const A5& a5) : MockClass(a1, a2, a3, a4, a5) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
-      const A5& a5, const A6& a6) : MockClass(a1, a2, a3, a4, a5, a6) {}
+      const A5& a5, const A6& a6) : MockClass(a1, a2, a3, a4, a5, a6) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7) : MockClass(a1, a2, a3, a4, a5,
-      a6, a7) {}
+      a6, a7) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8) : MockClass(a1,
-      a2, a3, a4, a5, a6, a7, a8) {}
+      a2, a3, a4, a5, a6, a7, a8) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8, typename A9>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8,
-      const A9& a9) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9) {}
+      const A9& a9) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8, typename A9, typename A10>
   NaggyMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8, const A9& a9,
-      const A10& a10) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {}
+      const A10& a10) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {
+    ::testing::Mock::WarnUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
 #endif  // GTEST_LANG_CXX11
 
+  ~NaggyMock() {
+    ::testing::Mock::UnregisterCallReaction(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
+
  private:
   GTEST_DISALLOW_COPY_AND_ASSIGN_(NaggyMock);
 };
 
-namespace internal {
-
-template <typename MockClass>
-NaggyMockBase<MockClass>::NaggyMockBase() {
-  ::testing::Mock::WarnUninterestingCalls(
-      internal::ImplicitCast_<MockClass*>(
-          static_cast<NaggyMock<MockClass> *>(this)));
-}
-
-template <typename MockClass>
-NaggyMockBase<MockClass>::~NaggyMockBase() {
-  ::testing::Mock::UnregisterCallReaction(
-      internal::ImplicitCast_<MockClass*>(
-          static_cast<NaggyMock<MockClass>*>(this)));
-}
-
-}  // namespace internal
-
-namespace internal {
-
-// StrictMockBase serves as a mix-in to establish the "uninteresting call"
-// behavior for StrictMock on construction. It accomplishes this via CRTP to get
-// access to the derived MockClass.
 template <class MockClass>
-class StrictMockBase {
- protected:
-  StrictMockBase();
-
-  ~StrictMockBase();
-};
-
-}  // namespace internal
-
-template <class MockClass>
-class StrictMock : public MockClass,
-    public internal::StrictMockBase<MockClass> {
+class StrictMock : public MockClass {
  public:
-  StrictMock() : MockClass() {}
+  StrictMock() : MockClass() {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
 #if GTEST_LANG_CXX11
-  // Ideally, we would inherit base class's constructors through a using
-  // declaration, which would preserve their visibility. However, many existing
-  // tests rely on the fact that current implementation reexports protected
-  // constructors as public. These tests would need to be cleaned up first.
-
   // Single argument constructor is special-cased so that it can be
   // made explicit.
   template <typename A>
-  explicit StrictMock(A&& arg) : MockClass(std::forward<A>(arg)) {}
+  explicit StrictMock(A&& arg) : MockClass(std::forward<A>(arg)) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename... An>
   StrictMock(A1&& arg1, A2&& arg2, An&&... args)
       : MockClass(std::forward<A1>(arg1), std::forward<A2>(arg2),
-                  std::forward<An>(args)...) {}
+                  std::forward<An>(args)...) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 #else
   // C++98 doesn't have variadic templates, so we have to define one
   // for each arity.
   template <typename A1>
-  explicit StrictMock(const A1& a1) : MockClass(a1) {}
+  explicit StrictMock(const A1& a1) : MockClass(a1) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
   template <typename A1, typename A2>
-  StrictMock(const A1& a1, const A2& a2) : MockClass(a1, a2) {}
+  StrictMock(const A1& a1, const A2& a2) : MockClass(a1, a2) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3>
-  StrictMock(const A1& a1, const A2& a2, const A3& a3) : MockClass(a1, a2,
-      a3) {}
+  StrictMock(const A1& a1, const A2& a2, const A3& a3) : MockClass(a1, a2, a3) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4>
   StrictMock(const A1& a1, const A2& a2, const A3& a3,
-      const A4& a4) : MockClass(a1, a2, a3, a4) {}
+      const A4& a4) : MockClass(a1, a2, a3, a4) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5>
   StrictMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
-      const A5& a5) : MockClass(a1, a2, a3, a4, a5) {}
+      const A5& a5) : MockClass(a1, a2, a3, a4, a5) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6>
   StrictMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
-      const A5& a5, const A6& a6) : MockClass(a1, a2, a3, a4, a5, a6) {}
+      const A5& a5, const A6& a6) : MockClass(a1, a2, a3, a4, a5, a6) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7>
   StrictMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7) : MockClass(a1, a2, a3, a4, a5,
-      a6, a7) {}
+      a6, a7) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8>
   StrictMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8) : MockClass(a1,
-      a2, a3, a4, a5, a6, a7, a8) {}
+      a2, a3, a4, a5, a6, a7, a8) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8, typename A9>
   StrictMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8,
-      const A9& a9) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9) {}
+      const A9& a9) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
   template <typename A1, typename A2, typename A3, typename A4, typename A5,
       typename A6, typename A7, typename A8, typename A9, typename A10>
   StrictMock(const A1& a1, const A2& a2, const A3& a3, const A4& a4,
       const A5& a5, const A6& a6, const A7& a7, const A8& a8, const A9& a9,
-      const A10& a10) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {}
+      const A10& a10) : MockClass(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {
+    ::testing::Mock::FailUninterestingCalls(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
 
 #endif  // GTEST_LANG_CXX11
 
+  ~StrictMock() {
+    ::testing::Mock::UnregisterCallReaction(
+        internal::ImplicitCast_<MockClass*>(this));
+  }
+
  private:
   GTEST_DISALLOW_COPY_AND_ASSIGN_(StrictMock);
 };
 
-namespace internal {
-
-template <typename MockClass>
-StrictMockBase<MockClass>::StrictMockBase() {
-  ::testing::Mock::FailUninterestingCalls(
-      internal::ImplicitCast_<MockClass*>(
-          static_cast<StrictMock<MockClass> *>(this)));
-}
-
-template <typename MockClass>
-StrictMockBase<MockClass>::~StrictMockBase() {
-  ::testing::Mock::UnregisterCallReaction(
-      internal::ImplicitCast_<MockClass*>(
-          static_cast<StrictMock<MockClass>*>(this)));
-}
-
-}  // namespace internal
-
 // The following specializations catch some (relatively more common)
 // user errors of nesting nice and strict mocks.  They do NOT catch
 // all possible errors.