gfe-relnote: n/a(new class type not in use) Add SimpleLinkedHashMap which is
forked from chromium linked_hash_map.h.
This class is not used in google3, but used by other platform, i.e.
chromium, envoy, etc.
PiperOrigin-RevId: 245234098
Change-Id: Id453c101c9d191ae509ceb4f92c85a7486802e60
diff --git a/common/platform/api/quiche_ptr_util.h b/common/platform/api/quiche_ptr_util.h
new file mode 100644
index 0000000..26b152b
--- /dev/null
+++ b/common/platform/api/quiche_ptr_util.h
@@ -0,0 +1,21 @@
+// Copyright (c) 2019 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 QUICHE_COMMON_PLATFORM_API_QUICHE_PTR_UTIL_H_
+#define QUICHE_COMMON_PLATFORM_API_QUICHE_PTR_UTIL_H_
+
+#include <memory>
+
+#include "net/quiche/common/platform/impl/quiche_ptr_util_impl.h"
+
+namespace quiche {
+
+template <typename T, typename... Args>
+std::unique_ptr<T> QuicheMakeUnique(Args&&... args) {
+ return QuicheMakeUniqueImpl<T>(std::forward<Args>(args)...);
+}
+
+} // namespace quiche
+
+#endif // QUICHE_COMMON_PLATFORM_API_QUICHE_PTR_UTIL_H_
diff --git a/common/platform/api/quiche_test.h b/common/platform/api/quiche_test.h
new file mode 100644
index 0000000..f51c85e
--- /dev/null
+++ b/common/platform/api/quiche_test.h
@@ -0,0 +1,10 @@
+// Copyright (c) 2019 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 QUICHE_COMMON_PLATFORM_API_QUICHE_TEST_H_
+#define QUICHE_COMMON_PLATFORM_API_QUICHE_TEST_H_
+
+#include "net/quiche/common/platform/impl/quiche_test_impl.h"
+
+#endif // QUICHE_COMMON_PLATFORM_API_QUICHE_TEST_H_
diff --git a/common/platform/api/quiche_unordered_containers.h b/common/platform/api/quiche_unordered_containers.h
new file mode 100644
index 0000000..583f97e
--- /dev/null
+++ b/common/platform/api/quiche_unordered_containers.h
@@ -0,0 +1,24 @@
+// Copyright (c) 2019 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 QUICHE_COMMON_PLATFORM_API_QUICHE_UNORDERED_CONTAINERS_H_
+#define QUICHE_COMMON_PLATFORM_API_QUICHE_UNORDERED_CONTAINERS_H_
+
+#include "net/quiche/common/platform/impl/quiche_unordered_containers_impl.h"
+
+namespace quiche {
+
+// The default hasher used by hash tables.
+template <typename Key>
+using QuicheDefaultHasher = QuicheDefaultHasherImpl<Key>;
+
+// A general-purpose unordered map.
+template <typename Key,
+ typename Value,
+ typename Hash = QuicheDefaultHasher<Key>>
+using QuicheUnorderedMap = QuicheUnorderedMapImpl<Key, Value, Hash>;
+
+} // namespace quiche
+
+#endif // QUICHE_COMMON_PLATFORM_API_QUICHE_UNORDERED_CONTAINERS_H_
diff --git a/common/simple_linked_hash_map.h b/common/simple_linked_hash_map.h
new file mode 100644
index 0000000..8ff1a2b
--- /dev/null
+++ b/common/simple_linked_hash_map.h
@@ -0,0 +1,245 @@
+// Copyright (c) 2019 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.
+
+// This is a simplistic insertion-ordered map. It behaves similarly to an STL
+// map, but only implements a small subset of the map's methods. Internally, we
+// just keep a map and a list going in parallel.
+//
+// This class provides no thread safety guarantees, beyond what you would
+// normally see with std::list.
+//
+// Iterators point into the list and should be stable in the face of
+// mutations, except for an iterator pointing to an element that was just
+// deleted.
+
+#ifndef QUICHE_COMMON_SIMPLE_LINKED_HASH_MAP_H_
+#define QUICHE_COMMON_SIMPLE_LINKED_HASH_MAP_H_
+
+#include <list>
+#include <tuple>
+#include <type_traits>
+#include <utility>
+
+#include "net/third_party/quiche/src/common/platform/api/quiche_unordered_containers.h"
+
+namespace quiche {
+
+// This holds a list of pair<Key, Value> items. This list is what gets
+// traversed, and it's iterators from this list that we return from
+// begin/end/find.
+//
+// We also keep a set<list::iterator> for find. Since std::list is a
+// doubly-linked list, the iterators should remain stable.
+
+template <class Key, class Value, class Hash = std::hash<Key>>
+class SimpleLinkedHashMap {
+ private:
+ typedef std::list<std::pair<Key, Value>> ListType;
+ typedef QuicheUnorderedMap<Key, typename ListType::iterator, Hash> MapType;
+
+ public:
+ typedef typename ListType::iterator iterator;
+ typedef typename ListType::reverse_iterator reverse_iterator;
+ typedef typename ListType::const_iterator const_iterator;
+ typedef typename ListType::const_reverse_iterator const_reverse_iterator;
+ typedef typename MapType::key_type key_type;
+ typedef typename ListType::value_type value_type;
+ typedef typename ListType::size_type size_type;
+
+ SimpleLinkedHashMap() = default;
+ explicit SimpleLinkedHashMap(size_type bucket_count) : map_(bucket_count) {}
+
+ SimpleLinkedHashMap(const SimpleLinkedHashMap& other) = delete;
+ SimpleLinkedHashMap& operator=(const SimpleLinkedHashMap& other) = delete;
+ SimpleLinkedHashMap(SimpleLinkedHashMap&& other) = default;
+ SimpleLinkedHashMap& operator=(SimpleLinkedHashMap&& other) = default;
+
+ // Returns an iterator to the first (insertion-ordered) element. Like a map,
+ // this can be dereferenced to a pair<Key, Value>.
+ iterator begin() { return list_.begin(); }
+ const_iterator begin() const { return list_.begin(); }
+
+ // Returns an iterator beyond the last element.
+ iterator end() { return list_.end(); }
+ const_iterator end() const { return list_.end(); }
+
+ // Returns an iterator to the last (insertion-ordered) element. Like a map,
+ // this can be dereferenced to a pair<Key, Value>.
+ reverse_iterator rbegin() { return list_.rbegin(); }
+ const_reverse_iterator rbegin() const { return list_.rbegin(); }
+
+ // Returns an iterator beyond the first element.
+ reverse_iterator rend() { return list_.rend(); }
+ const_reverse_iterator rend() const { return list_.rend(); }
+
+ // Front and back accessors common to many stl containers.
+
+ // Returns the earliest-inserted element
+ const value_type& front() const { return list_.front(); }
+
+ // Returns the earliest-inserted element.
+ value_type& front() { return list_.front(); }
+
+ // Returns the most-recently-inserted element.
+ const value_type& back() const { return list_.back(); }
+
+ // Returns the most-recently-inserted element.
+ value_type& back() { return list_.back(); }
+
+ // Clears the map of all values.
+ void clear() {
+ map_.clear();
+ list_.clear();
+ }
+
+ // Returns true iff the map is empty.
+ bool empty() const { return list_.empty(); }
+
+ // Removes the first element from the list.
+ void pop_front() { erase(begin()); }
+
+ // Erases values with the provided key. Returns the number of elements
+ // erased. In this implementation, this will be 0 or 1.
+ size_type erase(const Key& key) {
+ typename MapType::iterator found = map_.find(key);
+ if (found == map_.end()) {
+ return 0;
+ }
+
+ list_.erase(found->second);
+ map_.erase(found);
+
+ return 1;
+ }
+
+ // Erases the item that 'position' points to. Returns an iterator that points
+ // to the item that comes immediately after the deleted item in the list, or
+ // end().
+ // If the provided iterator is invalid or there is inconsistency between the
+ // map and list, a CHECK() error will occur.
+ iterator erase(iterator position) {
+ typename MapType::iterator found = map_.find(position->first);
+ CHECK(found->second == position)
+ << "Inconsisent iterator for map and list, or the iterator is invalid.";
+
+ map_.erase(found);
+ return list_.erase(position);
+ }
+
+ // Erases all the items in the range [first, last). Returns an iterator that
+ // points to the item that comes immediately after the last deleted item in
+ // the list, or end().
+ iterator erase(iterator first, iterator last) {
+ while (first != last && first != end()) {
+ first = erase(first);
+ }
+ return first;
+ }
+
+ // Finds the element with the given key. Returns an iterator to the
+ // value found, or to end() if the value was not found. Like a map, this
+ // iterator points to a pair<Key, Value>.
+ iterator find(const Key& key) {
+ typename MapType::iterator found = map_.find(key);
+ if (found == map_.end()) {
+ return end();
+ }
+ return found->second;
+ }
+
+ const_iterator find(const Key& key) const {
+ typename MapType::const_iterator found = map_.find(key);
+ if (found == map_.end()) {
+ return end();
+ }
+ return found->second;
+ }
+
+ bool contains(const Key& key) const { return find(key) != end(); }
+
+ // Returns the value mapped to key, or an inserted iterator to that position
+ // in the map.
+ Value& operator[](const key_type& key) {
+ return (*((this->insert(std::make_pair(key, Value()))).first)).second;
+ }
+
+ // Inserts an element into the map
+ std::pair<iterator, bool> insert(const std::pair<Key, Value>& pair) {
+ // First make sure the map doesn't have a key with this value. If it does,
+ // return a pair with an iterator to it, and false indicating that we
+ // didn't insert anything.
+ typename MapType::iterator found = map_.find(pair.first);
+ if (found != map_.end()) {
+ return std::make_pair(found->second, false);
+ }
+
+ // Otherwise, insert into the list first.
+ list_.push_back(pair);
+
+ // Obtain an iterator to the newly added element. We do -- instead of -
+ // since list::iterator doesn't implement operator-().
+ typename ListType::iterator last = list_.end();
+ --last;
+
+ CHECK(map_.insert(std::make_pair(pair.first, last)).second)
+ << "Map and list are inconsistent";
+
+ return std::make_pair(last, true);
+ }
+
+ // Inserts an element into the map
+ std::pair<iterator, bool> insert(std::pair<Key, Value>&& pair) {
+ // First make sure the map doesn't have a key with this value. If it does,
+ // return a pair with an iterator to it, and false indicating that we
+ // didn't insert anything.
+ typename MapType::iterator found = map_.find(pair.first);
+ if (found != map_.end()) {
+ return std::make_pair(found->second, false);
+ }
+
+ // Otherwise, insert into the list first.
+ list_.push_back(std::move(pair));
+
+ // Obtain an iterator to the newly added element. We do -- instead of -
+ // since list::iterator doesn't implement operator-().
+ typename ListType::iterator last = list_.end();
+ --last;
+
+ CHECK(map_.insert(std::make_pair(pair.first, last)).second)
+ << "Map and list are inconsistent";
+ return std::make_pair(last, true);
+ }
+
+ size_type size() const { return list_.size(); }
+
+ template <typename... Args>
+ std::pair<iterator, bool> emplace(Args&&... args) {
+ ListType node_donor;
+ auto node_pos =
+ node_donor.emplace(node_donor.end(), std::forward<Args>(args)...);
+ const auto& k = node_pos->first;
+ auto ins = map_.insert({k, node_pos});
+ if (!ins.second) {
+ return {ins.first->second, false};
+ }
+ list_.splice(list_.end(), node_donor, node_pos);
+ return {ins.first->second, true};
+ }
+
+ void swap(SimpleLinkedHashMap& other) {
+ map_.swap(other.map_);
+ list_.swap(other.list_);
+ }
+
+ private:
+ // The map component, used for speedy lookups
+ MapType map_;
+
+ // The list component, used for maintaining insertion order
+ ListType list_;
+};
+
+} // namespace quiche
+
+#endif // QUICHE_COMMON_SIMPLE_LINKED_HASH_MAP_H_
diff --git a/common/simple_linked_hash_map_test.cc b/common/simple_linked_hash_map_test.cc
new file mode 100644
index 0000000..00179b3
--- /dev/null
+++ b/common/simple_linked_hash_map_test.cc
@@ -0,0 +1,396 @@
+// Copyright (c) 2019 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.
+
+// Tests SimpleLinkedHashMap.
+
+#include "net/third_party/quiche/src/common/simple_linked_hash_map.h"
+
+#include <memory>
+#include <utility>
+
+#include "net/third_party/quiche/src/common/platform/api/quiche_ptr_util.h"
+#include "net/third_party/quiche/src/common/platform/api/quiche_test.h"
+
+using testing::Pair;
+using testing::Pointee;
+using testing::UnorderedElementsAre;
+
+namespace quiche {
+namespace test {
+
+// Tests that move constructor works.
+TEST(LinkedHashMapTest, Move) {
+ // Use unique_ptr as an example of a non-copyable type.
+ SimpleLinkedHashMap<int, std::unique_ptr<int>> m;
+ m[2] = QuicheMakeUnique<int>(12);
+ m[3] = QuicheMakeUnique<int>(13);
+ SimpleLinkedHashMap<int, std::unique_ptr<int>> n = std::move(m);
+ EXPECT_THAT(n,
+ UnorderedElementsAre(Pair(2, Pointee(12)), Pair(3, Pointee(13))));
+}
+
+TEST(LinkedHashMapTest, CanEmplaceMoveOnly) {
+ SimpleLinkedHashMap<int, std::unique_ptr<int>> m;
+ struct Data {
+ int k, v;
+ };
+ const Data data[] = {{1, 123}, {3, 345}, {2, 234}, {4, 456}};
+ for (const auto& kv : data) {
+ m.emplace(std::piecewise_construct, std::make_tuple(kv.k),
+ std::make_tuple(new int{kv.v}));
+ }
+ EXPECT_TRUE(m.contains(2));
+ auto found = m.find(2);
+ ASSERT_TRUE(found != m.end());
+ EXPECT_EQ(234, *found->second);
+}
+
+struct NoCopy {
+ explicit NoCopy(int x) : x(x) {}
+ NoCopy(const NoCopy&) = delete;
+ NoCopy& operator=(const NoCopy&) = delete;
+ NoCopy(NoCopy&&) = delete;
+ NoCopy& operator=(NoCopy&&) = delete;
+ int x;
+};
+
+TEST(LinkedHashMapTest, CanEmplaceNoMoveNoCopy) {
+ SimpleLinkedHashMap<int, NoCopy> m;
+ struct Data {
+ int k, v;
+ };
+ const Data data[] = {{1, 123}, {3, 345}, {2, 234}, {4, 456}};
+ for (const auto& kv : data) {
+ m.emplace(std::piecewise_construct, std::make_tuple(kv.k),
+ std::make_tuple(kv.v));
+ }
+ EXPECT_TRUE(m.contains(2));
+ auto found = m.find(2);
+ ASSERT_TRUE(found != m.end());
+ EXPECT_EQ(234, found->second.x);
+}
+
+TEST(LinkedHashMapTest, ConstKeys) {
+ SimpleLinkedHashMap<int, int> m;
+ m.insert(std::make_pair(1, 2));
+ // Test that keys are const in iteration.
+ std::pair<int, int>& p = *m.begin();
+ EXPECT_EQ(1, p.first);
+}
+
+// Tests that iteration from begin() to end() works
+TEST(LinkedHashMapTest, Iteration) {
+ SimpleLinkedHashMap<int, int> m;
+ EXPECT_TRUE(m.begin() == m.end());
+
+ m.insert(std::make_pair(2, 12));
+ m.insert(std::make_pair(1, 11));
+ m.insert(std::make_pair(3, 13));
+
+ SimpleLinkedHashMap<int, int>::iterator i = m.begin();
+ ASSERT_TRUE(m.begin() == i);
+ ASSERT_TRUE(m.end() != i);
+ EXPECT_EQ(2, i->first);
+ EXPECT_EQ(12, i->second);
+
+ ++i;
+ ASSERT_TRUE(m.end() != i);
+ EXPECT_EQ(1, i->first);
+ EXPECT_EQ(11, i->second);
+
+ ++i;
+ ASSERT_TRUE(m.end() != i);
+ EXPECT_EQ(3, i->first);
+ EXPECT_EQ(13, i->second);
+
+ ++i; // Should be the end of the line.
+ ASSERT_TRUE(m.end() == i);
+}
+
+// Tests that reverse iteration from rbegin() to rend() works
+TEST(LinkedHashMapTest, ReverseIteration) {
+ SimpleLinkedHashMap<int, int> m;
+ EXPECT_TRUE(m.rbegin() == m.rend());
+
+ m.insert(std::make_pair(2, 12));
+ m.insert(std::make_pair(1, 11));
+ m.insert(std::make_pair(3, 13));
+
+ SimpleLinkedHashMap<int, int>::reverse_iterator i = m.rbegin();
+ ASSERT_TRUE(m.rbegin() == i);
+ ASSERT_TRUE(m.rend() != i);
+ EXPECT_EQ(3, i->first);
+ EXPECT_EQ(13, i->second);
+
+ ++i;
+ ASSERT_TRUE(m.rend() != i);
+ EXPECT_EQ(1, i->first);
+ EXPECT_EQ(11, i->second);
+
+ ++i;
+ ASSERT_TRUE(m.rend() != i);
+ EXPECT_EQ(2, i->first);
+ EXPECT_EQ(12, i->second);
+
+ ++i; // Should be the end of the line.
+ ASSERT_TRUE(m.rend() == i);
+}
+
+// Tests that clear() works
+TEST(LinkedHashMapTest, Clear) {
+ SimpleLinkedHashMap<int, int> m;
+ m.insert(std::make_pair(2, 12));
+ m.insert(std::make_pair(1, 11));
+ m.insert(std::make_pair(3, 13));
+
+ ASSERT_EQ(3u, m.size());
+
+ m.clear();
+
+ EXPECT_EQ(0u, m.size());
+
+ m.clear(); // Make sure we can call it on an empty map.
+
+ EXPECT_EQ(0u, m.size());
+}
+
+// Tests that size() works.
+TEST(LinkedHashMapTest, Size) {
+ SimpleLinkedHashMap<int, int> m;
+ EXPECT_EQ(0u, m.size());
+ m.insert(std::make_pair(2, 12));
+ EXPECT_EQ(1u, m.size());
+ m.insert(std::make_pair(1, 11));
+ EXPECT_EQ(2u, m.size());
+ m.insert(std::make_pair(3, 13));
+ EXPECT_EQ(3u, m.size());
+ m.clear();
+ EXPECT_EQ(0u, m.size());
+}
+
+// Tests empty()
+TEST(LinkedHashMapTest, Empty) {
+ SimpleLinkedHashMap<int, int> m;
+ ASSERT_TRUE(m.empty());
+ m.insert(std::make_pair(2, 12));
+ ASSERT_FALSE(m.empty());
+ m.clear();
+ ASSERT_TRUE(m.empty());
+}
+
+TEST(LinkedHashMapTest, Erase) {
+ SimpleLinkedHashMap<int, int> m;
+ ASSERT_EQ(0u, m.size());
+ EXPECT_EQ(0, m.erase(2)); // Nothing to erase yet
+
+ m.insert(std::make_pair(2, 12));
+ ASSERT_EQ(1u, m.size());
+ EXPECT_EQ(1, m.erase(2));
+ EXPECT_EQ(0u, m.size());
+
+ EXPECT_EQ(0, m.erase(2)); // Make sure nothing bad happens if we repeat.
+ EXPECT_EQ(0u, m.size());
+}
+
+TEST(LinkedHashMapTest, Erase2) {
+ SimpleLinkedHashMap<int, int> m;
+ ASSERT_EQ(0u, m.size());
+ EXPECT_EQ(0, m.erase(2)); // Nothing to erase yet
+
+ m.insert(std::make_pair(2, 12));
+ m.insert(std::make_pair(1, 11));
+ m.insert(std::make_pair(3, 13));
+ m.insert(std::make_pair(4, 14));
+ ASSERT_EQ(4u, m.size());
+
+ // Erase middle two
+ EXPECT_EQ(1, m.erase(1));
+ EXPECT_EQ(1, m.erase(3));
+
+ EXPECT_EQ(2u, m.size());
+
+ // Make sure we can still iterate over everything that's left.
+ SimpleLinkedHashMap<int, int>::iterator it = m.begin();
+ ASSERT_TRUE(it != m.end());
+ EXPECT_EQ(12, it->second);
+ ++it;
+ ASSERT_TRUE(it != m.end());
+ EXPECT_EQ(14, it->second);
+ ++it;
+ ASSERT_TRUE(it == m.end());
+
+ EXPECT_EQ(0, m.erase(1)); // Make sure nothing bad happens if we repeat.
+ ASSERT_EQ(2u, m.size());
+
+ EXPECT_EQ(1, m.erase(2));
+ EXPECT_EQ(1, m.erase(4));
+ ASSERT_EQ(0u, m.size());
+
+ EXPECT_EQ(0, m.erase(1)); // Make sure nothing bad happens if we repeat.
+ ASSERT_EQ(0u, m.size());
+}
+
+// Test that erase(iter,iter) and erase(iter) compile and work.
+TEST(LinkedHashMapTest, Erase3) {
+ SimpleLinkedHashMap<int, int> m;
+
+ m.insert(std::make_pair(1, 11));
+ m.insert(std::make_pair(2, 12));
+ m.insert(std::make_pair(3, 13));
+ m.insert(std::make_pair(4, 14));
+
+ // Erase middle two
+ SimpleLinkedHashMap<int, int>::iterator it2 = m.find(2);
+ SimpleLinkedHashMap<int, int>::iterator it4 = m.find(4);
+ EXPECT_EQ(m.erase(it2, it4), m.find(4));
+ EXPECT_EQ(2, m.size());
+
+ // Make sure we can still iterate over everything that's left.
+ SimpleLinkedHashMap<int, int>::iterator it = m.begin();
+ ASSERT_TRUE(it != m.end());
+ EXPECT_EQ(11, it->second);
+ ++it;
+ ASSERT_TRUE(it != m.end());
+ EXPECT_EQ(14, it->second);
+ ++it;
+ ASSERT_TRUE(it == m.end());
+
+ // Erase first one using an iterator.
+ EXPECT_EQ(m.erase(m.begin()), m.find(4));
+
+ // Only the last element should be left.
+ it = m.begin();
+ ASSERT_TRUE(it != m.end());
+ EXPECT_EQ(14, it->second);
+ ++it;
+ ASSERT_TRUE(it == m.end());
+}
+
+TEST(LinkedHashMapTest, Insertion) {
+ SimpleLinkedHashMap<int, int> m;
+ ASSERT_EQ(0u, m.size());
+ std::pair<SimpleLinkedHashMap<int, int>::iterator, bool> result;
+
+ result = m.insert(std::make_pair(2, 12));
+ ASSERT_EQ(1u, m.size());
+ EXPECT_TRUE(result.second);
+ EXPECT_EQ(2, result.first->first);
+ EXPECT_EQ(12, result.first->second);
+
+ result = m.insert(std::make_pair(1, 11));
+ ASSERT_EQ(2u, m.size());
+ EXPECT_TRUE(result.second);
+ EXPECT_EQ(1, result.first->first);
+ EXPECT_EQ(11, result.first->second);
+
+ result = m.insert(std::make_pair(3, 13));
+ SimpleLinkedHashMap<int, int>::iterator result_iterator = result.first;
+ ASSERT_EQ(3u, m.size());
+ EXPECT_TRUE(result.second);
+ EXPECT_EQ(3, result.first->first);
+ EXPECT_EQ(13, result.first->second);
+
+ result = m.insert(std::make_pair(3, 13));
+ EXPECT_EQ(3u, m.size());
+ EXPECT_FALSE(result.second) << "No insertion should have occurred.";
+ EXPECT_TRUE(result_iterator == result.first)
+ << "Duplicate insertion should have given us the original iterator.";
+}
+
+static std::pair<int, int> Pair(int i, int j) {
+ return {i, j};
+}
+
+// Test front accessors.
+TEST(LinkedHashMapTest, Front) {
+ SimpleLinkedHashMap<int, int> m;
+
+ m.insert(std::make_pair(2, 12));
+ m.insert(std::make_pair(1, 11));
+ m.insert(std::make_pair(3, 13));
+
+ EXPECT_EQ(3u, m.size());
+ EXPECT_EQ(Pair(2, 12), m.front());
+ m.pop_front();
+ EXPECT_EQ(2u, m.size());
+ EXPECT_EQ(Pair(1, 11), m.front());
+ m.pop_front();
+ EXPECT_EQ(1u, m.size());
+ EXPECT_EQ(Pair(3, 13), m.front());
+ m.pop_front();
+ EXPECT_TRUE(m.empty());
+}
+
+TEST(LinkedHashMapTest, Find) {
+ SimpleLinkedHashMap<int, int> m;
+
+ EXPECT_TRUE(m.end() == m.find(1))
+ << "We shouldn't find anything in an empty map.";
+
+ m.insert(std::make_pair(2, 12));
+ EXPECT_TRUE(m.end() == m.find(1))
+ << "We shouldn't find an element that doesn't exist in the map.";
+
+ std::pair<SimpleLinkedHashMap<int, int>::iterator, bool> result =
+ m.insert(std::make_pair(1, 11));
+ ASSERT_TRUE(result.second);
+ ASSERT_TRUE(m.end() != result.first);
+ EXPECT_TRUE(result.first == m.find(1))
+ << "We should have found an element we know exists in the map.";
+ EXPECT_EQ(11, result.first->second);
+
+ // Check that a follow-up insertion doesn't affect our original
+ m.insert(std::make_pair(3, 13));
+ SimpleLinkedHashMap<int, int>::iterator it = m.find(1);
+ ASSERT_TRUE(m.end() != it);
+ EXPECT_EQ(11, it->second);
+
+ m.clear();
+ EXPECT_TRUE(m.end() == m.find(1))
+ << "We shouldn't find anything in a map that we've cleared.";
+}
+
+TEST(LinkedHashMapTest, Contains) {
+ SimpleLinkedHashMap<int, int> m;
+
+ EXPECT_FALSE(m.contains(1)) << "An empty map shouldn't contain anything.";
+
+ m.insert(std::make_pair(2, 12));
+ EXPECT_FALSE(m.contains(1))
+ << "The map shouldn't contain an element that doesn't exist.";
+
+ m.insert(std::make_pair(1, 11));
+ EXPECT_TRUE(m.contains(1))
+ << "The map should contain an element that we know exists.";
+
+ m.clear();
+ EXPECT_FALSE(m.contains(1))
+ << "A map that we've cleared shouldn't contain anything.";
+}
+
+TEST(LinkedHashMapTest, Swap) {
+ SimpleLinkedHashMap<int, int> m1;
+ SimpleLinkedHashMap<int, int> m2;
+ m1.insert(std::make_pair(1, 1));
+ m1.insert(std::make_pair(2, 2));
+ m2.insert(std::make_pair(3, 3));
+ ASSERT_EQ(2u, m1.size());
+ ASSERT_EQ(1u, m2.size());
+ m1.swap(m2);
+ ASSERT_EQ(1u, m1.size());
+ ASSERT_EQ(2u, m2.size());
+}
+
+TEST(LinkedHashMapTest, CustomHashAndEquality) {
+ struct CustomIntHash {
+ size_t operator()(int x) const { return x; }
+ };
+ SimpleLinkedHashMap<int, int, CustomIntHash> m;
+ m.insert(std::make_pair(1, 1));
+ EXPECT_TRUE(m.contains(1));
+ EXPECT_EQ(1, m[1]);
+}
+
+} // namespace test
+} // namespace quiche
