chromium/base/containers/checked_iterators_unittest.cc

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/containers/checked_iterators.h"

#include <algorithm>
#include <iterator>

#include "base/check_op.h"
#include "base/debug/alias.h"
#include "base/ranges/algorithm.h"
#include "base/test/gtest_util.h"
#include "build/build_config.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace base {

TEST(CheckedContiguousIterator, SatisfiesContiguousIteratorConcept) { … }

template <class T, size_t N>
constexpr CheckedContiguousConstIterator<T> MakeConstIter(T (&arr)[N],
                                                          size_t cur) { … }

template <class T, size_t N>
constexpr CheckedContiguousIterator<T> MakeIter(T (&arr)[N], size_t cur) { … }

// Checks that constexpr CheckedContiguousConstIterators can be compared at
// compile time.
TEST(CheckedContiguousIterator, StaticComparisonOperators) { … }

// Checks that comparison between iterators and const iterators works in both
// directions.
TEST(CheckedContiguousIterator, ConvertingComparisonOperators) { … }

TEST(CheckedContiguousIteratorDeathTest, OutOfBounds) { … }

}  // namespace base

namespace {

// Helper template that wraps an iterator and disables its dereference and
// increment operations.
template <typename Iterator>
struct DisableDerefAndIncr : Iterator { … };

}  // namespace

// Inherit `pointer_traits` specialization from the base class.
pointer_traits<DisableDerefAndIncr<Iter>>;

namespace base {

// Tests that using std::copy with CheckedContiguousIterator<int> results in an
// optimized code-path that does not invoke the iterator's dereference and
// increment operations, as expected in libc++. This fails to compile if
// std::copy is not optimized.
// NOTE: This test relies on implementation details of the STL and thus might
// break in the future during a libc++ roll. If this does happen, please reach
// out to [email protected] to reevaluate whether this test will
// still be needed.
#if defined(_LIBCPP_VERSION)
TEST(CheckedContiguousIterator, OptimizedCopy) { … }
#endif  // defined(_LIBCPP_VERSION)

}  // namespace base