Change nonstd::unique_ptr to take a custom deleter.

third_party/base/nonstd_unique_ptr_unittest.cpp

+// Copyright 2015 PDFium 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 <sstream>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "macros.h"
+#include "nonstd_unique_ptr.h"
+
+using nonstd::unique_ptr;
+
+namespace {
+
+// Used to test depth subtyping.
+class ConDecLoggerParent {
+ public:
+  virtual ~ConDecLoggerParent() {}
+
+  virtual void SetPtr(int* ptr) = 0;
+
+  virtual int SomeMeth(int x) const = 0;
+};
+
+class ConDecLogger : public ConDecLoggerParent {

[Tom Sepez, 2015/09/22 17:36:20]

Actually, I want to steal this file to test nonstd::move(), do you want to land
first or do you want to merge?

[Lei Zhang, 2015/09/23 00:38:56]

All yours.

+ public:
+  ConDecLogger() : ptr_(nullptr) {}
+  explicit ConDecLogger(int* ptr) { SetPtr(ptr); }
+  ~ConDecLogger() override { --*ptr_; }

[Jeffrey Yasskin, 2015/09/19 00:00:48]

Is "Dec" an abbreviation for "Destruction"?

[Lei Zhang, 2015/09/23 00:38:56]

Tom renamed this in his CL.

+
+  void SetPtr(int* ptr) override {
+    ptr_ = ptr;
+    ++*ptr_;
+  }
+
+  int SomeMeth(int x) const override { return x; }
+
+ private:
+  int* ptr_;
+
+  // Disallow evil constructors.
+  ConDecLogger(const ConDecLogger&) = delete;
+  void operator=(const ConDecLogger&) = delete;
+};
+
+struct CountingDeleter {
+  explicit CountingDeleter(int* count) : count_(count) {}
+  inline void operator()(double* ptr) const { (*count_)++; }
+  int* count_;
+};
+
+// Do not delete this function!  It's existence is to test that you can
+// return a temporarily constructed version of the scoper.
+unique_ptr<ConDecLogger> TestReturnOfType(int* constructed) {
+  return unique_ptr<ConDecLogger>(new ConDecLogger(constructed));
+}
+
+}  // namespace
+
+TEST(UniquePtrTest, UniquePtr) {
+  int constructed = 0;
+
+  // Ensure size of unique_ptr<> doesn't increase unexpectedly.
+  static_assert(sizeof(int*) >= sizeof(unique_ptr<int>),
+                "unique_ptr_larger_than_raw_ptr");
+
+  {
+    unique_ptr<ConDecLogger> scoper(new ConDecLogger(&constructed));
+    EXPECT_EQ(1, constructed);
+    EXPECT_TRUE(scoper.get());
+
+    EXPECT_EQ(10, scoper->SomeMeth(10));
+    EXPECT_EQ(10, scoper.get()->SomeMeth(10));
+    EXPECT_EQ(10, (*scoper).SomeMeth(10));
+  }
+  EXPECT_EQ(0, constructed);
+
+  // Test reset() and release()
+  {
+    unique_ptr<ConDecLogger> scoper(new ConDecLogger(&constructed));
+    EXPECT_EQ(1, constructed);
+    EXPECT_TRUE(scoper.get());
+
+    scoper.reset(new ConDecLogger(&constructed));
+    EXPECT_EQ(1, constructed);
+    EXPECT_TRUE(scoper.get());
+
+    scoper.reset();
+    EXPECT_EQ(0, constructed);
+    EXPECT_FALSE(scoper.get());
+
+    scoper.reset(new ConDecLogger(&constructed));
+    EXPECT_EQ(1, constructed);
+    EXPECT_TRUE(scoper.get());
+
+    ConDecLogger* take = scoper.release();
+    EXPECT_EQ(1, constructed);
+    EXPECT_FALSE(scoper.get());
+    delete take;
+    EXPECT_EQ(0, constructed);
+
+    scoper.reset(new ConDecLogger(&constructed));
+    EXPECT_EQ(1, constructed);
+    EXPECT_TRUE(scoper.get());
+  }
+  EXPECT_EQ(0, constructed);
+
+  // Test swap(), == and !=
+  {
+    unique_ptr<ConDecLogger> scoper1;
+    unique_ptr<ConDecLogger> scoper2;
+    EXPECT_TRUE(scoper1 == scoper2.get());
+    EXPECT_FALSE(scoper1 != scoper2.get());
+
+    ConDecLogger* logger = new ConDecLogger(&constructed);
+    scoper1.reset(logger);
+    EXPECT_EQ(logger, scoper1.get());
+    EXPECT_FALSE(scoper2.get());
+    EXPECT_FALSE(scoper1 == scoper2.get());
+    EXPECT_TRUE(scoper1 != scoper2.get());
+
+    scoper2.swap(scoper1);
+    EXPECT_EQ(logger, scoper2.get());
+    EXPECT_FALSE(scoper1.get());
+    EXPECT_FALSE(scoper1 == scoper2.get());
+    EXPECT_TRUE(scoper1 != scoper2.get());
+  }
+  EXPECT_EQ(0, constructed);
+}
+
+TEST(UniquePtrTest, UniquePtrWithArray) {
+  static const int kNumLoggers = 12;
+
+  int constructed = 0;
+
+  {
+    unique_ptr<ConDecLogger[]> scoper(new ConDecLogger[kNumLoggers]);
+    EXPECT_TRUE(scoper);
+    EXPECT_EQ(&scoper[0], scoper.get());
+    for (int i = 0; i < kNumLoggers; ++i) {
+      scoper[i].SetPtr(&constructed);
+    }
+    EXPECT_EQ(12, constructed);
+
+    EXPECT_EQ(10, scoper.get()->SomeMeth(10));
+    EXPECT_EQ(10, scoper[2].SomeMeth(10));
+  }
+  EXPECT_EQ(0, constructed);
+
+  // Test reset() and release()
+  {
+    unique_ptr<ConDecLogger[]> scoper;
+    EXPECT_FALSE(scoper.get());
+    EXPECT_FALSE(scoper.release());
+    EXPECT_FALSE(scoper.get());
+    scoper.reset();
+    EXPECT_FALSE(scoper.get());
+
+    scoper.reset(new ConDecLogger[kNumLoggers]);
+    for (int i = 0; i < kNumLoggers; ++i) {
+      scoper[i].SetPtr(&constructed);
+    }
+    EXPECT_EQ(12, constructed);
+    scoper.reset();
+    EXPECT_EQ(0, constructed);
+
+    scoper.reset(new ConDecLogger[kNumLoggers]);
+    for (int i = 0; i < kNumLoggers; ++i) {
+      scoper[i].SetPtr(&constructed);
+    }
+    EXPECT_EQ(12, constructed);
+    ConDecLogger* ptr = scoper.release();
+    EXPECT_EQ(12, constructed);
+    delete[] ptr;
+    EXPECT_EQ(0, constructed);
+  }
+  EXPECT_EQ(0, constructed);
+
+  // Test swap(), ==, !=, and type-safe Boolean.
+  {
+    unique_ptr<ConDecLogger[]> scoper1;
+    unique_ptr<ConDecLogger[]> scoper2;
+    EXPECT_TRUE(scoper1 == scoper2.get());
+    EXPECT_FALSE(scoper1 != scoper2.get());
+
+    ConDecLogger* loggers = new ConDecLogger[kNumLoggers];
+    for (int i = 0; i < kNumLoggers; ++i) {
+      loggers[i].SetPtr(&constructed);
+    }
+    scoper1.reset(loggers);
+    EXPECT_TRUE(scoper1);
+    EXPECT_EQ(loggers, scoper1.get());
+    EXPECT_FALSE(scoper2);
+    EXPECT_FALSE(scoper2.get());
+    EXPECT_FALSE(scoper1 == scoper2.get());
+    EXPECT_TRUE(scoper1 != scoper2.get());
+
+    scoper2.swap(scoper1);
+    EXPECT_EQ(loggers, scoper2.get());
+    EXPECT_FALSE(scoper1.get());
+    EXPECT_FALSE(scoper1 == scoper2.get());
+    EXPECT_TRUE(scoper1 != scoper2.get());
+  }
+  EXPECT_EQ(0, constructed);
+}
+
+TEST(UniquePtrTest, ReturnTypeBehavior) {
+  int constructed = 0;
+
+  // Test that we can return a unique_ptr.
+  {
+    ConDecLogger* logger = new ConDecLogger(&constructed);
+    unique_ptr<ConDecLogger> scoper(logger);
+    EXPECT_EQ(1, constructed);
+  }
+  EXPECT_EQ(0, constructed);
+
+  // Test uncaught return type not leak.
+  {
+    ConDecLogger* logger = new ConDecLogger(&constructed);
+    unique_ptr<ConDecLogger> scoper(logger);
+    EXPECT_EQ(1, constructed);
+  }
+  EXPECT_EQ(0, constructed);
+
+  // Call TestReturnOfType() so the compiler doesn't warn for an unused
+  // function.
+  { TestReturnOfType(&constructed); }
+  EXPECT_EQ(0, constructed);
+}
+
+TEST(UniquePtrTest, CustomDeleter) {
+  double dummy_value;  // Custom deleter never touches this value.
+  int deletes = 0;
+  int alternate_deletes = 0;
+
+  // Normal delete support.
+  {
+    deletes = 0;
+    unique_ptr<double, CountingDeleter> scoper(&dummy_value,
+                                               CountingDeleter(&deletes));
+    EXPECT_EQ(0, deletes);
+    EXPECT_TRUE(scoper.get());
+  }
+  EXPECT_EQ(1, deletes);
+
+  // Test reset() and release().
+  deletes = 0;
+  {
+    unique_ptr<double, CountingDeleter> scoper(nullptr,
+                                               CountingDeleter(&deletes));
+    EXPECT_FALSE(scoper.get());
+    EXPECT_FALSE(scoper.release());
+    EXPECT_FALSE(scoper.get());
+    scoper.reset();
+    EXPECT_FALSE(scoper.get());
+    EXPECT_EQ(0, deletes);
+
+    scoper.reset(&dummy_value);
+    scoper.reset();
+    EXPECT_EQ(1, deletes);
+
+    scoper.reset(&dummy_value);
+    EXPECT_EQ(&dummy_value, scoper.release());
+  }
+  EXPECT_EQ(1, deletes);
+
+  // Test get_deleter().
+  deletes = 0;
+  alternate_deletes = 0;
+  {
+    unique_ptr<double, CountingDeleter> scoper(&dummy_value,
+                                               CountingDeleter(&deletes));
+    // Call deleter manually.
+    EXPECT_EQ(0, deletes);
+    scoper.get_deleter()(&dummy_value);
+    EXPECT_EQ(1, deletes);
+
+    // Deleter is still there after reset.
+    scoper.reset();
+    EXPECT_EQ(2, deletes);
+    scoper.get_deleter()(&dummy_value);
+    EXPECT_EQ(3, deletes);
+
+    // Deleter can be assigned into (matches C++11 unique_ptr<> spec).
+    scoper.get_deleter() = CountingDeleter(&alternate_deletes);
+    scoper.reset(&dummy_value);
+    EXPECT_EQ(0, alternate_deletes);
+  }
+  EXPECT_EQ(3, deletes);
+  EXPECT_EQ(1, alternate_deletes);
+
+  // Test swap(), ==, !=, and type-safe Boolean.
+  {
+    unique_ptr<double, CountingDeleter> scoper1(nullptr,
+                                                CountingDeleter(&deletes));
+    unique_ptr<double, CountingDeleter> scoper2(nullptr,
+                                                CountingDeleter(&deletes));
+    EXPECT_TRUE(scoper1 == scoper2.get());
+    EXPECT_FALSE(scoper1 != scoper2.get());
+
+    scoper1.reset(&dummy_value);
+    EXPECT_TRUE(scoper1);
+    EXPECT_EQ(&dummy_value, scoper1.get());
+    EXPECT_FALSE(scoper2);
+    EXPECT_FALSE(scoper2.get());
+    EXPECT_FALSE(scoper1 == scoper2.get());
+    EXPECT_TRUE(scoper1 != scoper2.get());
+
+    scoper2.swap(scoper1);
+    EXPECT_EQ(&dummy_value, scoper2.get());
+    EXPECT_FALSE(scoper1.get());
+    EXPECT_FALSE(scoper1 == scoper2.get());
+    EXPECT_TRUE(scoper1 != scoper2.get());
+  }
+}
+
+unique_ptr<int> NullIntReturn() {
+  return nullptr;
+}
+
+TEST(UniquePtrTest, Nullptr) {
+  unique_ptr<int> scoper1(nullptr);
+  unique_ptr<int> scoper2(new int);
+  scoper2 = nullptr;
+  unique_ptr<int> scoper3(NullIntReturn());
+  unique_ptr<int> scoper4 = NullIntReturn();
+  EXPECT_EQ(nullptr, scoper1.get());
+  EXPECT_EQ(nullptr, scoper2.get());
+  EXPECT_EQ(nullptr, scoper3.get());
+  EXPECT_EQ(nullptr, scoper4.get());
+}
+
+unique_ptr<int[]> NullIntArrayReturn() {
+  return nullptr;
+}
+
+TEST(UniquePtrTest, NullptrArray) {
+  unique_ptr<int[]> scoper1(nullptr);
+  unique_ptr<int[]> scoper2(new int[3]);
+  scoper2 = nullptr;
+  unique_ptr<int[]> scoper3(NullIntArrayReturn());
+  unique_ptr<int[]> scoper4 = NullIntArrayReturn();
+  EXPECT_EQ(nullptr, scoper1.get());
+  EXPECT_EQ(nullptr, scoper2.get());
+  EXPECT_EQ(nullptr, scoper3.get());
+  EXPECT_EQ(nullptr, scoper4.get());
+}
+
+// Logging a unique_ptr<T> to an ostream shouldn't convert it to a boolean
+// value first.
+TEST(ScopedPtrTest, LoggingDoesntConvertToBoolean) {
+  unique_ptr<int> x(new int);
+  std::stringstream s1;
+  s1 << x;
+
+  std::stringstream s2;
+  s2 << x.get();
+
+  EXPECT_EQ(s2.str(), s1.str());
+}