blob: 07b0144f987cc5b94c2123cd2b00e360b5818696 [file] [log] [blame]
// Copyright (c) 2011 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 "base/containers/mru_cache.h"
#include <cstddef>
#include <memory>
#include "base/memory/ptr_util.h"
#include "base/trace_event/memory_usage_estimator.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace base {
namespace {
int cached_item_live_count = 0;
struct CachedItem {
CachedItem() : value(0) {
cached_item_live_count++;
}
explicit CachedItem(int new_value) : value(new_value) {
cached_item_live_count++;
}
explicit CachedItem(const CachedItem& other) : value(other.value) {
cached_item_live_count++;
}
~CachedItem() {
cached_item_live_count--;
}
int value;
};
} // namespace
TEST(MRUCacheTest, Basic) {
typedef base::MRUCache<int, CachedItem> Cache;
Cache cache(Cache::NO_AUTO_EVICT);
// Check failure conditions
{
CachedItem test_item;
EXPECT_TRUE(cache.Get(0) == cache.end());
EXPECT_TRUE(cache.Peek(0) == cache.end());
}
static const int kItem1Key = 5;
CachedItem item1(10);
auto inserted_item = cache.Put(kItem1Key, item1);
EXPECT_EQ(1U, cache.size());
// Check that item1 was properly inserted.
{
auto found = cache.Get(kItem1Key);
EXPECT_TRUE(inserted_item == cache.begin());
EXPECT_TRUE(found != cache.end());
found = cache.Peek(kItem1Key);
EXPECT_TRUE(found != cache.end());
EXPECT_EQ(kItem1Key, found->first);
EXPECT_EQ(item1.value, found->second.value);
}
static const int kItem2Key = 7;
CachedItem item2(12);
cache.Put(kItem2Key, item2);
EXPECT_EQ(2U, cache.size());
// Check that item1 is the oldest since item2 was added afterwards.
{
auto oldest = cache.rbegin();
ASSERT_TRUE(oldest != cache.rend());
EXPECT_EQ(kItem1Key, oldest->first);
EXPECT_EQ(item1.value, oldest->second.value);
}
// Check that item1 is still accessible by key.
{
auto test_item = cache.Get(kItem1Key);
ASSERT_TRUE(test_item != cache.end());
EXPECT_EQ(kItem1Key, test_item->first);
EXPECT_EQ(item1.value, test_item->second.value);
}
// Check that retrieving item1 pushed item2 to oldest.
{
auto oldest = cache.rbegin();
ASSERT_TRUE(oldest != cache.rend());
EXPECT_EQ(kItem2Key, oldest->first);
EXPECT_EQ(item2.value, oldest->second.value);
}
// Remove the oldest item and check that item1 is now the only member.
{
auto next = cache.Erase(cache.rbegin());
EXPECT_EQ(1U, cache.size());
EXPECT_TRUE(next == cache.rbegin());
EXPECT_EQ(kItem1Key, next->first);
EXPECT_EQ(item1.value, next->second.value);
cache.Erase(cache.begin());
EXPECT_EQ(0U, cache.size());
}
// Check that Clear() works properly.
cache.Put(kItem1Key, item1);
cache.Put(kItem2Key, item2);
EXPECT_EQ(2U, cache.size());
cache.Clear();
EXPECT_EQ(0U, cache.size());
}
TEST(MRUCacheTest, GetVsPeek) {
typedef base::MRUCache<int, CachedItem> Cache;
Cache cache(Cache::NO_AUTO_EVICT);
static const int kItem1Key = 1;
CachedItem item1(10);
cache.Put(kItem1Key, item1);
static const int kItem2Key = 2;
CachedItem item2(20);
cache.Put(kItem2Key, item2);
// This should do nothing since the size is bigger than the number of items.
cache.ShrinkToSize(100);
// Check that item1 starts out as oldest
{
auto iter = cache.rbegin();
ASSERT_TRUE(iter != cache.rend());
EXPECT_EQ(kItem1Key, iter->first);
EXPECT_EQ(item1.value, iter->second.value);
}
// Check that Peek doesn't change ordering
{
auto peekiter = cache.Peek(kItem1Key);
ASSERT_TRUE(peekiter != cache.end());
auto iter = cache.rbegin();
ASSERT_TRUE(iter != cache.rend());
EXPECT_EQ(kItem1Key, iter->first);
EXPECT_EQ(item1.value, iter->second.value);
}
}
TEST(MRUCacheTest, KeyReplacement) {
typedef base::MRUCache<int, CachedItem> Cache;
Cache cache(Cache::NO_AUTO_EVICT);
static const int kItem1Key = 1;
CachedItem item1(10);
cache.Put(kItem1Key, item1);
static const int kItem2Key = 2;
CachedItem item2(20);
cache.Put(kItem2Key, item2);
static const int kItem3Key = 3;
CachedItem item3(30);
cache.Put(kItem3Key, item3);
static const int kItem4Key = 4;
CachedItem item4(40);
cache.Put(kItem4Key, item4);
CachedItem item5(50);
cache.Put(kItem3Key, item5);
EXPECT_EQ(4U, cache.size());
for (int i = 0; i < 3; ++i) {
auto iter = cache.rbegin();
ASSERT_TRUE(iter != cache.rend());
}
// Make it so only the most important element is there.
cache.ShrinkToSize(1);
auto iter = cache.begin();
EXPECT_EQ(kItem3Key, iter->first);
EXPECT_EQ(item5.value, iter->second.value);
}
// Make sure that the owning version release its pointers properly.
TEST(MRUCacheTest, Owning) {
using Cache = base::MRUCache<int, std::unique_ptr<CachedItem>>;
Cache cache(Cache::NO_AUTO_EVICT);
int initial_count = cached_item_live_count;
// First insert and item and then overwrite it.
static const int kItem1Key = 1;
cache.Put(kItem1Key, WrapUnique(new CachedItem(20)));
cache.Put(kItem1Key, WrapUnique(new CachedItem(22)));
// There should still be one item, and one extra live item.
auto iter = cache.Get(kItem1Key);
EXPECT_EQ(1U, cache.size());
EXPECT_TRUE(iter != cache.end());
EXPECT_EQ(initial_count + 1, cached_item_live_count);
// Now remove it.
cache.Erase(cache.begin());
EXPECT_EQ(initial_count, cached_item_live_count);
// Now try another cache that goes out of scope to make sure its pointers
// go away.
{
Cache cache2(Cache::NO_AUTO_EVICT);
cache2.Put(1, WrapUnique(new CachedItem(20)));
cache2.Put(2, WrapUnique(new CachedItem(20)));
}
// There should be no objects leaked.
EXPECT_EQ(initial_count, cached_item_live_count);
// Check that Clear() also frees things correctly.
{
Cache cache2(Cache::NO_AUTO_EVICT);
cache2.Put(1, WrapUnique(new CachedItem(20)));
cache2.Put(2, WrapUnique(new CachedItem(20)));
EXPECT_EQ(initial_count + 2, cached_item_live_count);
cache2.Clear();
EXPECT_EQ(initial_count, cached_item_live_count);
}
}
TEST(MRUCacheTest, AutoEvict) {
using Cache = base::MRUCache<int, std::unique_ptr<CachedItem>>;
static const Cache::size_type kMaxSize = 3;
int initial_count = cached_item_live_count;
{
Cache cache(kMaxSize);
static const int kItem1Key = 1, kItem2Key = 2, kItem3Key = 3, kItem4Key = 4;
cache.Put(kItem1Key, std::make_unique<CachedItem>(20));
cache.Put(kItem2Key, std::make_unique<CachedItem>(21));
cache.Put(kItem3Key, std::make_unique<CachedItem>(22));
cache.Put(kItem4Key, std::make_unique<CachedItem>(23));
// The cache should only have kMaxSize items in it even though we inserted
// more.
EXPECT_EQ(kMaxSize, cache.size());
}
// There should be no objects leaked.
EXPECT_EQ(initial_count, cached_item_live_count);
}
TEST(MRUCacheTest, HashingMRUCache) {
// Very simple test to make sure that the hashing cache works correctly.
typedef base::HashingMRUCache<std::string, CachedItem> Cache;
Cache cache(Cache::NO_AUTO_EVICT);
CachedItem one(1);
cache.Put("First", one);
CachedItem two(2);
cache.Put("Second", two);
EXPECT_EQ(one.value, cache.Get("First")->second.value);
EXPECT_EQ(two.value, cache.Get("Second")->second.value);
cache.ShrinkToSize(1);
EXPECT_EQ(two.value, cache.Get("Second")->second.value);
EXPECT_TRUE(cache.Get("First") == cache.end());
}
TEST(MRUCacheTest, Swap) {
typedef base::MRUCache<int, CachedItem> Cache;
Cache cache1(Cache::NO_AUTO_EVICT);
// Insert two items into cache1.
static const int kItem1Key = 1;
CachedItem item1(2);
auto inserted_item = cache1.Put(kItem1Key, item1);
EXPECT_EQ(1U, cache1.size());
static const int kItem2Key = 3;
CachedItem item2(4);
cache1.Put(kItem2Key, item2);
EXPECT_EQ(2U, cache1.size());
// Verify cache1's elements.
{
auto iter = cache1.begin();
ASSERT_TRUE(iter != cache1.end());
EXPECT_EQ(kItem2Key, iter->first);
EXPECT_EQ(item2.value, iter->second.value);
++iter;
ASSERT_TRUE(iter != cache1.end());
EXPECT_EQ(kItem1Key, iter->first);
EXPECT_EQ(item1.value, iter->second.value);
}
// Create another cache2.
Cache cache2(Cache::NO_AUTO_EVICT);
// Insert three items into cache2.
static const int kItem3Key = 5;
CachedItem item3(6);
inserted_item = cache2.Put(kItem3Key, item3);
EXPECT_EQ(1U, cache2.size());
static const int kItem4Key = 7;
CachedItem item4(8);
cache2.Put(kItem4Key, item4);
EXPECT_EQ(2U, cache2.size());
static const int kItem5Key = 9;
CachedItem item5(10);
cache2.Put(kItem5Key, item5);
EXPECT_EQ(3U, cache2.size());
// Verify cache2's elements.
{
auto iter = cache2.begin();
ASSERT_TRUE(iter != cache2.end());
EXPECT_EQ(kItem5Key, iter->first);
EXPECT_EQ(item5.value, iter->second.value);
++iter;
ASSERT_TRUE(iter != cache2.end());
EXPECT_EQ(kItem4Key, iter->first);
EXPECT_EQ(item4.value, iter->second.value);
++iter;
ASSERT_TRUE(iter != cache2.end());
EXPECT_EQ(kItem3Key, iter->first);
EXPECT_EQ(item3.value, iter->second.value);
}
// Swap cache1 and cache2 and verify cache2 has cache1's elements and cache1
// has cache2's elements.
cache2.Swap(cache1);
EXPECT_EQ(3U, cache1.size());
EXPECT_EQ(2U, cache2.size());
// Verify cache1's elements.
{
auto iter = cache1.begin();
ASSERT_TRUE(iter != cache1.end());
EXPECT_EQ(kItem5Key, iter->first);
EXPECT_EQ(item5.value, iter->second.value);
++iter;
ASSERT_TRUE(iter != cache1.end());
EXPECT_EQ(kItem4Key, iter->first);
EXPECT_EQ(item4.value, iter->second.value);
++iter;
ASSERT_TRUE(iter != cache1.end());
EXPECT_EQ(kItem3Key, iter->first);
EXPECT_EQ(item3.value, iter->second.value);
}
// Verify cache2's elements.
{
auto iter = cache2.begin();
ASSERT_TRUE(iter != cache2.end());
EXPECT_EQ(kItem2Key, iter->first);
EXPECT_EQ(item2.value, iter->second.value);
++iter;
ASSERT_TRUE(iter != cache2.end());
EXPECT_EQ(kItem1Key, iter->first);
EXPECT_EQ(item1.value, iter->second.value);
}
}
TEST(MRUCacheTest, EstimateMemory) {
base::MRUCache<std::string, int> cache(10);
const std::string key(100u, 'a');
cache.Put(key, 1);
EXPECT_GT(trace_event::EstimateMemoryUsage(cache),
trace_event::EstimateMemoryUsage(key));
}
} // namespace base