1 files changed, 131 insertions, 0 deletions
diff --git a/mfbt/tests/TestRefPtr.cpp b/mfbt/tests/TestRefPtr.cpp
new file mode 100644
index 0000000000..972e284c44
--- /dev/null
+++ b/mfbt/tests/TestRefPtr.cpp
@@ -0,0 +1,131 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/RefPtr.h"
+#include "mozilla/RefCounted.h"
+
+#include <type_traits>
+
+using mozilla::RefCounted;
+
+class Foo : public RefCounted<Foo> {
+ public:
+  MOZ_DECLARE_REFCOUNTED_TYPENAME(Foo)
+
+  Foo() : mDead(false) {}
+
+  static int sNumDestroyed;
+
+  ~Foo() {
+    MOZ_ASSERT(!mDead);
+    mDead = true;
+    sNumDestroyed++;
+  }
+
+ private:
+  bool mDead;
+};
+int Foo::sNumDestroyed;
+
+struct Bar : public Foo {};
+
+already_AddRefed<Foo> NewFoo() {
+  RefPtr<Foo> f(new Foo());
+  return f.forget();
+}
+
+already_AddRefed<Foo> NewBar() {
+  RefPtr<Bar> bar = new Bar();
+  return bar.forget();
+}
+
+void GetNewFoo(Foo** aFoo) {
+  *aFoo = new Bar();
+  // Kids, don't try this at home
+  (*aFoo)->AddRef();
+}
+
+void GetNewFoo(RefPtr<Foo>* aFoo) { *aFoo = new Bar(); }
+
+already_AddRefed<Foo> GetNullFoo() { return 0; }
+
+int main() {
+  MOZ_RELEASE_ASSERT(0 == Foo::sNumDestroyed);
+  {
+    RefPtr<Foo> f = new Foo();
+    MOZ_RELEASE_ASSERT(f->refCount() == 1);
+  }
+  MOZ_RELEASE_ASSERT(1 == Foo::sNumDestroyed);
+
+  {
+    RefPtr f1 = NewFoo();
+    static_assert(std::is_same_v<decltype(f1), RefPtr<Foo>>);
+    RefPtr f2(NewFoo());
+    static_assert(std::is_same_v<decltype(f2), RefPtr<Foo>>);
+    MOZ_RELEASE_ASSERT(1 == Foo::sNumDestroyed);
+  }
+  MOZ_RELEASE_ASSERT(3 == Foo::sNumDestroyed);
+
+  {
+    RefPtr<Foo> b = NewBar();
+    MOZ_RELEASE_ASSERT(3 == Foo::sNumDestroyed);
+  }
+  MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed);
+
+  {
+    RefPtr<Foo> f1;
+    {
+      f1 = new Foo();
+      RefPtr<Foo> f2(f1);
+      RefPtr<Foo> f3 = f2;
+      MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed);
+    }
+    MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed);
+  }
+  MOZ_RELEASE_ASSERT(5 == Foo::sNumDestroyed);
+
+  {
+    {
+      RefPtr<Foo> f = new Foo();
+      RefPtr<Foo> g = f.forget();
+    }
+    MOZ_RELEASE_ASSERT(6 == Foo::sNumDestroyed);
+  }
+
+  {
+    RefPtr<Foo> f = new Foo();
+    GetNewFoo(getter_AddRefs(f));
+    MOZ_RELEASE_ASSERT(7 == Foo::sNumDestroyed);
+  }
+  MOZ_RELEASE_ASSERT(8 == Foo::sNumDestroyed);
+
+  {
+    RefPtr<Foo> f = new Foo();
+    GetNewFoo(&f);
+    MOZ_RELEASE_ASSERT(9 == Foo::sNumDestroyed);
+  }
+  MOZ_RELEASE_ASSERT(10 == Foo::sNumDestroyed);
+
+  { RefPtr<Foo> f1 = new Bar(); }
+  MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed);
+
+  {
+    RefPtr f = GetNullFoo();
+    static_assert(std::is_same_v<decltype(f), RefPtr<Foo>>);
+    MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed);
+  }
+  MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed);
+
+  {
+    bool condition = true;
+    const auto f =
+        condition ? mozilla::MakeRefPtr<Bar>() : mozilla::MakeRefPtr<Foo>();
+
+    MOZ_RELEASE_ASSERT(f);
+  }
+
+  return 0;
+}