Check for public dtors on base::RefCounted types

tools/clang/plugins/tests/base_refcounted.h

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_REFCOUNTED_H_
+#define BASE_REFCOUNTED_H_
+
+namespace base {
+
+template <typename T>
+class RefCounted {
+ public:
+  RefCounted() {}
+  ~RefCounted() {}
+};
+
+template <typename T>
+class RefCountedThreadSafe {
+ public:
+  RefCountedThreadSafe() {}
+  ~RefCountedThreadSafe() {}
+};
+
+}  // namespace base
+
+// Ignore classes whose inheritance tree ends in WebKit's RefCounted base
+// class. Though prone to error, this pattern is very prevalent in WebKit
+// code, so do not issue any warnings.
+namespace WebKit {
+
+template <typename T>
+class RefCounted {
+ public:
+  RefCounted() {}
+  ~RefCounted() {}
+};
+
+}  // namespace WebKit
+
+// Unsafe; should error.
+class PublicRefCountedDtorInHeader
+    : public base::RefCounted<PublicRefCountedDtorInHeader> {
+ public:
+  PublicRefCountedDtorInHeader() {}
+  ~PublicRefCountedDtorInHeader() {}
+
+ private:
+  friend class base::RefCounted<PublicRefCountedDtorInHeader>;
+};
+
+// Unsafe; should error.
+class PublicRefCountedThreadSafeDtorInHeader
+    : public base::RefCountedThreadSafe<
+          PublicRefCountedThreadSafeDtorInHeader> {
+ public:
+  PublicRefCountedThreadSafeDtorInHeader() {}
+  ~PublicRefCountedThreadSafeDtorInHeader() {}
+
+ private:
+  friend class base::RefCountedThreadSafe<
+      PublicRefCountedThreadSafeDtorInHeader>;
+};
+
+// Safe; should not have errors.
+class ProtectedRefCountedDtorInHeader
+    : public base::RefCounted<ProtectedRefCountedDtorInHeader> {
+ public:
+  ProtectedRefCountedDtorInHeader() {}
+
+ protected:
+  ~ProtectedRefCountedDtorInHeader() {}
+
+ private:
+  friend class base::RefCounted<ProtectedRefCountedDtorInHeader>;
+};
+
+// Safe; should not have errors.
+class PrivateRefCountedDtorInHeader
+    : public base::RefCounted<PrivateRefCountedDtorInHeader> {
+ public:
+  PrivateRefCountedDtorInHeader() {}
+
+ private:
+  ~PrivateRefCountedDtorInHeader() {}
+  friend class base::RefCounted<PrivateRefCountedDtorInHeader>;
+};
+
+// Unsafe; A grandchild class ends up exposing their parent and grandparent's
+// destructors.
+class DerivedProtectedToPublicInHeader
+    : public ProtectedRefCountedDtorInHeader {
+ public:
+  DerivedProtectedToPublicInHeader() {}
+  ~DerivedProtectedToPublicInHeader() {}
+};
+
+// Unsafe; A grandchild ends up implicitly exposing their parent and
+// grantparent's destructors.
+class ImplicitDerivedProtectedToPublicInHeader
+    : public ProtectedRefCountedDtorInHeader {
+ public:
+  ImplicitDerivedProtectedToPublicInHeader() {}
+};
+
+// Unsafe-but-ignored; should not have errors.
+class WebKitPublicDtorInHeader
+    : public WebKit::RefCounted<WebKitPublicDtorInHeader> {
+ public:
+  WebKitPublicDtorInHeader() {}
+  ~WebKitPublicDtorInHeader() {}
+};
+
+// Unsafe-but-ignored; should not have errors.
+class WebKitDerivedPublicDtorInHeader
+    : public WebKitPublicDtorInHeader {
+ public:
+  WebKitDerivedPublicDtorInHeader() {}
+  ~WebKitDerivedPublicDtorInHeader() {}
+};
+
+#endif  // BASE_REFCOUNTED_H_