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