Add ScopedGeneric.

base/scoped_generic_unittest.cc

+// Copyright 2014 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.
+
+#include <vector>
+
+#include "base/scoped_generic.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+
+namespace {
+
+struct IntTraits {
+  IntTraits(std::vector<int>* freed) : freed_ints(freed) {}
+
+  static int InvalidValue() {
+    return -1;
+  }
+  void Free(int value) {
+    freed_ints->push_back(value);
+  }
+
+  std::vector<int>* freed_ints;
+};
+
+typedef ScopedGeneric<int, IntTraits> ScopedInt;
+
+}  // namespace
+
+TEST(ScopedGenericTest, ScopedGeneric) {
+  std::vector<int> values_freed;
+  IntTraits traits(&values_freed);
+
+  // Invalid case, delete should not be called.
+  {
+    ScopedInt a(IntTraits::InvalidValue(), traits);
+  }
+  EXPECT_TRUE(values_freed.empty());
+
+  // Simple deleting case.
+  static const int kFirst = 0;
+  {
+    ScopedInt a(kFirst, traits);
+  }
+  ASSERT_EQ(1u, values_freed.size());
+  ASSERT_EQ(kFirst, values_freed[0]);
+  values_freed.clear();
+
+  // Release should return the right value and leave the object empty.
+  {
+    ScopedInt a(kFirst, traits);
+    EXPECT_EQ(kFirst, a.release());
+
+    ScopedInt b(IntTraits::InvalidValue(), traits);
+    EXPECT_EQ(IntTraits::InvalidValue(), b.release());
+  }
+  ASSERT_TRUE(values_freed.empty());
+
+  // Reset should free the old value, then the new one should go away when
+  // it goes out of scope.
+  static const int kSecond = 1;
+  {
+    ScopedInt b(kFirst, traits);
+    b.reset(kSecond);
+    ASSERT_EQ(1u, values_freed.size());
+    ASSERT_EQ(kFirst, values_freed[0]);
+  }
+  ASSERT_EQ(2u, values_freed.size());
+  ASSERT_EQ(kSecond, values_freed[1]);
+  values_freed.clear();
+
+  // Swap.
+  {
+    ScopedInt a(kFirst, traits);
+    ScopedInt b(kSecond, traits);
+    a.swap(b);
+    EXPECT_TRUE(values_freed.empty());  // Nothing should be freed.
+    EXPECT_EQ(kSecond, a.get());
+    EXPECT_EQ(kFirst, b.get());
+  }
+  // Values should be deleted in the opposite order.
+  ASSERT_EQ(2u, values_freed.size());
+  EXPECT_EQ(kFirst, values_freed[0]);
+  EXPECT_EQ(kSecond, values_freed[1]);
+  values_freed.clear();
+
+  // Pass.
+  {
+    ScopedInt a(kFirst, traits);
+    ScopedInt b(a.Pass());
+    EXPECT_TRUE(values_freed.empty());  // Nothing should be freed.
+    ASSERT_EQ(IntTraits::InvalidValue(), a.get());
+    ASSERT_EQ(kFirst, b.get());
+  }
+  ASSERT_EQ(1u, values_freed.size());
+  ASSERT_EQ(kFirst, values_freed[0]);
+}
+
+TEST(ScopedGenericTest, Operators) {
+  std::vector<int> values_freed;
+  IntTraits traits(&values_freed);
+
+  static const int kFirst = 0;
+  static const int kSecond = 1;
+  {
+    ScopedInt a(kFirst, traits);
+    EXPECT_TRUE(a == kFirst);
+    EXPECT_FALSE(a != kFirst);
+    EXPECT_FALSE(a == kSecond);
+    EXPECT_TRUE(a != kSecond);
+
+    EXPECT_TRUE(kFirst == a);
+    EXPECT_FALSE(kFirst != a);
+    EXPECT_FALSE(kSecond == a);
+    EXPECT_TRUE(kSecond != a);
+  }
+
+  // is_valid().
+  {
+    ScopedInt a(kFirst, traits);
+    EXPECT_TRUE(a.is_valid());
+    a.reset();
+    EXPECT_FALSE(a.is_valid());
+  }
+}
+
+// Cheesy manual "no compile" test for manually validating changes.
+#if 0
+TEST(ScopedGenericTest, NoCompile) {
+  // Assignment shouldn't work.
+  /*{
+    ScopedInt a(kFirst, traits);
+    ScopedInt b(a);
+  }*/
+
+  // Comparison shouldn't work.
+  /*{
+    ScopedInt a(kFirst, traits);
+    ScopedInt b(kFirst, traits);
+    if (a == b) {
+    }
+  }*/
+
+  // Implicit conversion to bool shouldn't work.
+  /*{
+    ScopedInt a(kFirst, traits);
+    bool result = a;
+  }*/
+}
+#endif
+
+}  // namespace base