content/browser/dom_storage/dom_storage_area_unittest.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/bind.h"
   6 #include "base/files/file_util.h"
   7 #include "base/files/scoped_temp_dir.h"
   8 #include "base/message_loop/message_loop.h"
   9 #include "base/message_loop/message_loop_proxy.h"
  10 #include "base/strings/utf_string_conversions.h"
  11 #include "base/threading/sequenced_worker_pool.h"
  12 #include "base/time/time.h"
  13 #include "content/browser/dom_storage/dom_storage_area.h"
  14 #include "content/browser/dom_storage/dom_storage_database.h"
  15 #include "content/browser/dom_storage/dom_storage_database_adapter.h"
  16 #include "content/browser/dom_storage/dom_storage_task_runner.h"
  17 #include "content/browser/dom_storage/local_storage_database_adapter.h"
  18 #include "content/common/dom_storage/dom_storage_types.h"
  19 #include "testing/gtest/include/gtest/gtest.h"
  20
  21 using base::ASCIIToUTF16;
  22
  23 namespace content {
  24
  25 class DOMStorageAreaTest : public testing::Test {
  26  public:
  27   DOMStorageAreaTest()
  28     : kOrigin(GURL("http://dom_storage/")),
  29       kKey(ASCIIToUTF16("key")),
  30       kValue(ASCIIToUTF16("value")),
  31       kKey2(ASCIIToUTF16("key2")),
  32       kValue2(ASCIIToUTF16("value2")) {
  33   }
  34
  35   const GURL kOrigin;
  36   const base::string16 kKey;
  37   const base::string16 kValue;
  38   const base::string16 kKey2;
  39   const base::string16 kValue2;
  40
  41   // Method used in the CommitTasks test case.
  42   void InjectedCommitSequencingTask(DOMStorageArea* area) {
  43     // At this point the OnCommitTimer has run.
  44     // Verify that it put a commit in flight.
  45     EXPECT_EQ(1, area->commit_batches_in_flight_);
  46     EXPECT_FALSE(area->commit_batch_.get());
  47     EXPECT_TRUE(area->HasUncommittedChanges());
  48     // Make additional change and verify that a new commit batch
  49     // is created for that change.
  50     base::NullableString16 old_value;
  51     EXPECT_TRUE(area->SetItem(kKey2, kValue2, &old_value));
  52     EXPECT_TRUE(area->commit_batch_.get());
  53     EXPECT_EQ(1, area->commit_batches_in_flight_);
  54     EXPECT_TRUE(area->HasUncommittedChanges());
  55   }
  56
  57   // Class used in the CommitChangesAtShutdown test case.
  58   class VerifyChangesCommittedDatabase : public DOMStorageDatabase {
  59    public:
  60     VerifyChangesCommittedDatabase() {}
  61     ~VerifyChangesCommittedDatabase() override {
  62       const base::string16 kKey(ASCIIToUTF16("key"));
  63       const base::string16 kValue(ASCIIToUTF16("value"));
  64       DOMStorageValuesMap values;
  65       ReadAllValues(&values);
  66       EXPECT_EQ(1u, values.size());
  67       EXPECT_EQ(kValue, values[kKey].string());
  68     }
  69   };
  70
  71  private:
  72   base::MessageLoop message_loop_;
  73 };
  74
  75 TEST_F(DOMStorageAreaTest, DOMStorageAreaBasics) {
  76   scoped_refptr<DOMStorageArea> area(
  77       new DOMStorageArea(1, std::string(), kOrigin, NULL, NULL));
  78   base::string16 old_value;
  79   base::NullableString16 old_nullable_value;
  80   scoped_refptr<DOMStorageArea> copy;
  81
  82   // We don't focus on the underlying DOMStorageMap functionality
  83   // since that's covered by seperate unit tests.
  84   EXPECT_EQ(kOrigin, area->origin());
  85   EXPECT_EQ(1, area->namespace_id());
  86   EXPECT_EQ(0u, area->Length());
  87   EXPECT_TRUE(area->SetItem(kKey, kValue, &old_nullable_value));
  88   EXPECT_TRUE(area->SetItem(kKey2, kValue2, &old_nullable_value));
  89   EXPECT_FALSE(area->HasUncommittedChanges());
  90
  91   // Verify that a copy shares the same map.
  92   copy = area->ShallowCopy(2, std::string());
  93   EXPECT_EQ(kOrigin, copy->origin());
  94   EXPECT_EQ(2, copy->namespace_id());
  95   EXPECT_EQ(area->Length(), copy->Length());
  96   EXPECT_EQ(area->GetItem(kKey).string(), copy->GetItem(kKey).string());
  97   EXPECT_EQ(area->Key(0).string(), copy->Key(0).string());
  98   EXPECT_EQ(copy->map_.get(), area->map_.get());
  99
 100   // But will deep copy-on-write as needed.
 101   EXPECT_TRUE(area->RemoveItem(kKey, &old_value));
 102   EXPECT_NE(copy->map_.get(), area->map_.get());
 103   copy = area->ShallowCopy(2, std::string());
 104   EXPECT_EQ(copy->map_.get(), area->map_.get());
 105   EXPECT_TRUE(area->SetItem(kKey, kValue, &old_nullable_value));
 106   EXPECT_NE(copy->map_.get(), area->map_.get());
 107   copy = area->ShallowCopy(2, std::string());
 108   EXPECT_EQ(copy->map_.get(), area->map_.get());
 109   EXPECT_NE(0u, area->Length());
 110   EXPECT_TRUE(area->Clear());
 111   EXPECT_EQ(0u, area->Length());
 112   EXPECT_NE(copy->map_.get(), area->map_.get());
 113
 114   // Verify that once Shutdown(), behaves that way.
 115   area->Shutdown();
 116   EXPECT_TRUE(area->is_shutdown_);
 117   EXPECT_FALSE(area->map_.get());
 118   EXPECT_EQ(0u, area->Length());
 119   EXPECT_TRUE(area->Key(0).is_null());
 120   EXPECT_TRUE(area->GetItem(kKey).is_null());
 121   EXPECT_FALSE(area->SetItem(kKey, kValue, &old_nullable_value));
 122   EXPECT_FALSE(area->RemoveItem(kKey, &old_value));
 123   EXPECT_FALSE(area->Clear());
 124 }
 125
 126 TEST_F(DOMStorageAreaTest, BackingDatabaseOpened) {
 127   const int64 kSessionStorageNamespaceId = kLocalStorageNamespaceId + 1;
 128   base::ScopedTempDir temp_dir;
 129   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 130   const base::FilePath kExpectedOriginFilePath = temp_dir.path().Append(
 131       DOMStorageArea::DatabaseFileNameFromOrigin(kOrigin));
 132
 133   // No directory, backing should be null.
 134   {
 135     scoped_refptr<DOMStorageArea> area(
 136         new DOMStorageArea(kOrigin, base::FilePath(), NULL));
 137     EXPECT_EQ(NULL, area->backing_.get());
 138     EXPECT_TRUE(area->is_initial_import_done_);
 139     EXPECT_FALSE(base::PathExists(kExpectedOriginFilePath));
 140   }
 141
 142   // Valid directory and origin but no session storage backing. Backing should
 143   // be null.
 144   {
 145     scoped_refptr<DOMStorageArea> area(
 146         new DOMStorageArea(kSessionStorageNamespaceId, std::string(), kOrigin,
 147                            NULL, NULL));
 148     EXPECT_EQ(NULL, area->backing_.get());
 149     EXPECT_TRUE(area->is_initial_import_done_);
 150
 151     base::NullableString16 old_value;
 152     EXPECT_TRUE(area->SetItem(kKey, kValue, &old_value));
 153     ASSERT_TRUE(old_value.is_null());
 154
 155     // Check that saving a value has still left us without a backing database.
 156     EXPECT_EQ(NULL, area->backing_.get());
 157     EXPECT_FALSE(base::PathExists(kExpectedOriginFilePath));
 158   }
 159
 160   // This should set up a DOMStorageArea that is correctly backed to disk.
 161   {
 162     scoped_refptr<DOMStorageArea> area(new DOMStorageArea(
 163         kOrigin,
 164         temp_dir.path(),
 165         new MockDOMStorageTaskRunner(base::MessageLoopProxy::current().get())));
 166
 167     EXPECT_TRUE(area->backing_.get());
 168     DOMStorageDatabase* database = static_cast<LocalStorageDatabaseAdapter*>(
 169         area->backing_.get())->db_.get();
 170     EXPECT_FALSE(database->IsOpen());
 171     EXPECT_FALSE(area->is_initial_import_done_);
 172
 173     // Inject an in-memory db to speed up the test.
 174     // We will verify that something is written into the database but not
 175     // that a file is written to disk - DOMStorageDatabase unit tests cover
 176     // that.
 177     area->backing_.reset(new LocalStorageDatabaseAdapter());
 178
 179     // Need to write something to ensure that the database is created.
 180     base::NullableString16 old_value;
 181     EXPECT_TRUE(area->SetItem(kKey, kValue, &old_value));
 182     ASSERT_TRUE(old_value.is_null());
 183     EXPECT_TRUE(area->is_initial_import_done_);
 184     EXPECT_TRUE(area->commit_batch_.get());
 185     EXPECT_EQ(0, area->commit_batches_in_flight_);
 186
 187     base::MessageLoop::current()->RunUntilIdle();
 188
 189     EXPECT_FALSE(area->commit_batch_.get());
 190     EXPECT_EQ(0, area->commit_batches_in_flight_);
 191     database = static_cast<LocalStorageDatabaseAdapter*>(
 192         area->backing_.get())->db_.get();
 193     EXPECT_TRUE(database->IsOpen());
 194     EXPECT_EQ(1u, area->Length());
 195     EXPECT_EQ(kValue, area->GetItem(kKey).string());
 196
 197     // Verify the content made it to the in memory database.
 198     DOMStorageValuesMap values;
 199     area->backing_->ReadAllValues(&values);
 200     EXPECT_EQ(1u, values.size());
 201     EXPECT_EQ(kValue, values[kKey].string());
 202   }
 203 }
 204
 205 TEST_F(DOMStorageAreaTest, CommitTasks) {
 206   base::ScopedTempDir temp_dir;
 207   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 208
 209   scoped_refptr<DOMStorageArea> area(new DOMStorageArea(
 210       kOrigin,
 211       temp_dir.path(),
 212       new MockDOMStorageTaskRunner(base::MessageLoopProxy::current().get())));
 213   // Inject an in-memory db to speed up the test.
 214   area->backing_.reset(new LocalStorageDatabaseAdapter());
 215
 216   // Unrelated to commits, but while we're here, see that querying Length()
 217   // causes the backing database to be opened and presumably read from.
 218   EXPECT_FALSE(area->is_initial_import_done_);
 219   EXPECT_EQ(0u, area->Length());
 220   EXPECT_TRUE(area->is_initial_import_done_);
 221
 222   DOMStorageValuesMap values;
 223   base::NullableString16 old_value;
 224
 225   // See that changes are batched up.
 226   EXPECT_FALSE(area->commit_batch_.get());
 227   EXPECT_TRUE(area->SetItem(kKey, kValue, &old_value));
 228   EXPECT_TRUE(area->HasUncommittedChanges());
 229   EXPECT_TRUE(area->commit_batch_.get());
 230   EXPECT_FALSE(area->commit_batch_->clear_all_first);
 231   EXPECT_EQ(1u, area->commit_batch_->changed_values.size());
 232   EXPECT_TRUE(area->SetItem(kKey2, kValue2, &old_value));
 233   EXPECT_TRUE(area->commit_batch_.get());
 234   EXPECT_FALSE(area->commit_batch_->clear_all_first);
 235   EXPECT_EQ(2u, area->commit_batch_->changed_values.size());
 236   base::MessageLoop::current()->RunUntilIdle();
 237   EXPECT_FALSE(area->HasUncommittedChanges());
 238   EXPECT_FALSE(area->commit_batch_.get());
 239   EXPECT_EQ(0, area->commit_batches_in_flight_);
 240   // Verify the changes made it to the database.
 241   values.clear();
 242   area->backing_->ReadAllValues(&values);
 243   EXPECT_EQ(2u, values.size());
 244   EXPECT_EQ(kValue, values[kKey].string());
 245   EXPECT_EQ(kValue2, values[kKey2].string());
 246
 247   // See that clear is handled properly.
 248   EXPECT_TRUE(area->Clear());
 249   EXPECT_TRUE(area->commit_batch_.get());
 250   EXPECT_TRUE(area->commit_batch_->clear_all_first);
 251   EXPECT_TRUE(area->commit_batch_->changed_values.empty());
 252   base::MessageLoop::current()->RunUntilIdle();
 253   EXPECT_FALSE(area->commit_batch_.get());
 254   EXPECT_EQ(0, area->commit_batches_in_flight_);
 255   // Verify the changes made it to the database.
 256   values.clear();
 257   area->backing_->ReadAllValues(&values);
 258   EXPECT_TRUE(values.empty());
 259
 260   // See that if changes accrue while a commit is "in flight"
 261   // those will also get committed.
 262   EXPECT_TRUE(area->SetItem(kKey, kValue, &old_value));
 263   EXPECT_TRUE(area->HasUncommittedChanges());
 264   // At this point the OnCommitTimer task has been posted. We inject
 265   // another task in the queue that will execute after the timer task,
 266   // but before the CommitChanges task. From within our injected task,
 267   // we'll make an additional SetItem() call.
 268   base::MessageLoop::current()->PostTask(
 269       FROM_HERE,
 270       base::Bind(&DOMStorageAreaTest::InjectedCommitSequencingTask,
 271                  base::Unretained(this),
 272                  area));
 273   base::MessageLoop::current()->RunUntilIdle();
 274   EXPECT_TRUE(area->HasOneRef());
 275   EXPECT_FALSE(area->HasUncommittedChanges());
 276   // Verify the changes made it to the database.
 277   values.clear();
 278   area->backing_->ReadAllValues(&values);
 279   EXPECT_EQ(2u, values.size());
 280   EXPECT_EQ(kValue, values[kKey].string());
 281   EXPECT_EQ(kValue2, values[kKey2].string());
 282 }
 283
 284 TEST_F(DOMStorageAreaTest, CommitChangesAtShutdown) {
 285   base::ScopedTempDir temp_dir;
 286   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 287   scoped_refptr<DOMStorageArea> area(new DOMStorageArea(
 288       kOrigin,
 289       temp_dir.path(),
 290       new MockDOMStorageTaskRunner(base::MessageLoopProxy::current().get())));
 291
 292   // Inject an in-memory db to speed up the test and also to verify
 293   // the final changes are commited in it's dtor.
 294   static_cast<LocalStorageDatabaseAdapter*>(area->backing_.get())->db_.reset(
 295       new VerifyChangesCommittedDatabase());
 296
 297   DOMStorageValuesMap values;
 298   base::NullableString16 old_value;
 299   EXPECT_TRUE(area->SetItem(kKey, kValue, &old_value));
 300   EXPECT_TRUE(area->HasUncommittedChanges());
 301   area->backing_->ReadAllValues(&values);
 302   EXPECT_TRUE(values.empty());  // not committed yet
 303   area->Shutdown();
 304   base::MessageLoop::current()->RunUntilIdle();
 305   EXPECT_TRUE(area->HasOneRef());
 306   EXPECT_FALSE(area->backing_.get());
 307   // The VerifyChangesCommittedDatabase destructor verifies values
 308   // were committed.
 309 }
 310
 311 TEST_F(DOMStorageAreaTest, DeleteOrigin) {
 312   base::ScopedTempDir temp_dir;
 313   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 314   scoped_refptr<DOMStorageArea> area(new DOMStorageArea(
 315       kOrigin,
 316       temp_dir.path(),
 317       new MockDOMStorageTaskRunner(base::MessageLoopProxy::current().get())));
 318
 319   // This test puts files on disk.
 320   base::FilePath db_file_path = static_cast<LocalStorageDatabaseAdapter*>(
 321       area->backing_.get())->db_->file_path();
 322   base::FilePath db_journal_file_path =
 323       DOMStorageDatabase::GetJournalFilePath(db_file_path);
 324
 325   // Nothing bad should happen when invoked w/o any files on disk.
 326   area->DeleteOrigin();
 327   EXPECT_FALSE(base::PathExists(db_file_path));
 328
 329   // Commit something in the database and then delete.
 330   base::NullableString16 old_value;
 331   area->SetItem(kKey, kValue, &old_value);
 332   base::MessageLoop::current()->RunUntilIdle();
 333   EXPECT_TRUE(base::PathExists(db_file_path));
 334   area->DeleteOrigin();
 335   EXPECT_EQ(0u, area->Length());
 336   EXPECT_FALSE(base::PathExists(db_file_path));
 337   EXPECT_FALSE(base::PathExists(db_journal_file_path));
 338
 339   // Put some uncommitted changes to a non-existing database in
 340   // and then delete. No file ever gets created in this case.
 341   area->SetItem(kKey, kValue, &old_value);
 342   EXPECT_TRUE(area->HasUncommittedChanges());
 343   EXPECT_EQ(1u, area->Length());
 344   area->DeleteOrigin();
 345   EXPECT_TRUE(area->HasUncommittedChanges());
 346   EXPECT_EQ(0u, area->Length());
 347   base::MessageLoop::current()->RunUntilIdle();
 348   EXPECT_FALSE(area->HasUncommittedChanges());
 349   EXPECT_FALSE(base::PathExists(db_file_path));
 350
 351   // Put some uncommitted changes to a an existing database in
 352   // and then delete.
 353   area->SetItem(kKey, kValue, &old_value);
 354   base::MessageLoop::current()->RunUntilIdle();
 355   EXPECT_TRUE(base::PathExists(db_file_path));
 356   area->SetItem(kKey2, kValue2, &old_value);
 357   EXPECT_TRUE(area->HasUncommittedChanges());
 358   EXPECT_EQ(2u, area->Length());
 359   area->DeleteOrigin();
 360   EXPECT_TRUE(area->HasUncommittedChanges());
 361   EXPECT_EQ(0u, area->Length());
 362   base::MessageLoop::current()->RunUntilIdle();
 363   EXPECT_FALSE(area->HasUncommittedChanges());
 364   // Since the area had uncommitted changes at the time delete
 365   // was called, the file will linger until the shutdown time.
 366   EXPECT_TRUE(base::PathExists(db_file_path));
 367   area->Shutdown();
 368   base::MessageLoop::current()->RunUntilIdle();
 369   EXPECT_FALSE(base::PathExists(db_file_path));
 370 }
 371
 372 TEST_F(DOMStorageAreaTest, PurgeMemory) {
 373   base::ScopedTempDir temp_dir;
 374   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 375   scoped_refptr<DOMStorageArea> area(new DOMStorageArea(
 376       kOrigin,
 377       temp_dir.path(),
 378       new MockDOMStorageTaskRunner(base::MessageLoopProxy::current().get())));
 379
 380   // Inject an in-memory db to speed up the test.
 381   area->backing_.reset(new LocalStorageDatabaseAdapter());
 382
 383   // Unowned ptrs we use to verify that 'purge' has happened.
 384   DOMStorageDatabase* original_backing =
 385       static_cast<LocalStorageDatabaseAdapter*>(
 386           area->backing_.get())->db_.get();
 387   DOMStorageMap* original_map = area->map_.get();
 388
 389   // Should do no harm when called on a newly constructed object.
 390   EXPECT_FALSE(area->is_initial_import_done_);
 391   area->PurgeMemory();
 392   EXPECT_FALSE(area->is_initial_import_done_);
 393   DOMStorageDatabase* new_backing = static_cast<LocalStorageDatabaseAdapter*>(
 394       area->backing_.get())->db_.get();
 395   EXPECT_EQ(original_backing, new_backing);
 396   EXPECT_EQ(original_map, area->map_.get());
 397
 398   // Should not do anything when commits are pending.
 399   base::NullableString16 old_value;
 400   area->SetItem(kKey, kValue, &old_value);
 401   EXPECT_TRUE(area->is_initial_import_done_);
 402   EXPECT_TRUE(area->HasUncommittedChanges());
 403   area->PurgeMemory();
 404   EXPECT_TRUE(area->is_initial_import_done_);
 405   EXPECT_TRUE(area->HasUncommittedChanges());
 406   new_backing = static_cast<LocalStorageDatabaseAdapter*>(
 407       area->backing_.get())->db_.get();
 408   EXPECT_EQ(original_backing, new_backing);
 409   EXPECT_EQ(original_map, area->map_.get());
 410
 411   // Commit the changes from above,
 412   base::MessageLoop::current()->RunUntilIdle();
 413   EXPECT_FALSE(area->HasUncommittedChanges());
 414   new_backing = static_cast<LocalStorageDatabaseAdapter*>(
 415       area->backing_.get())->db_.get();
 416   EXPECT_EQ(original_backing, new_backing);
 417   EXPECT_EQ(original_map, area->map_.get());
 418
 419   // Should drop caches and reset database connections
 420   // when invoked on an area that's loaded up primed.
 421   area->PurgeMemory();
 422   EXPECT_FALSE(area->is_initial_import_done_);
 423   new_backing = static_cast<LocalStorageDatabaseAdapter*>(
 424       area->backing_.get())->db_.get();
 425   EXPECT_NE(original_backing, new_backing);
 426   EXPECT_NE(original_map, area->map_.get());
 427 }
 428
 429 TEST_F(DOMStorageAreaTest, DatabaseFileNames) {
 430   struct {
 431     const char* origin;
 432     const char* file_name;
 433     const char* journal_file_name;
 434   } kCases[] = {
 435     { "https://www.google.com/",
 436       "https_www.google.com_0.localstorage",
 437       "https_www.google.com_0.localstorage-journal" },
 438     { "http://www.google.com:8080/",
 439       "http_www.google.com_8080.localstorage",
 440       "http_www.google.com_8080.localstorage-journal" },
 441     { "file:///",
 442       "file__0.localstorage",
 443       "file__0.localstorage-journal" },
 444   };
 445
 446   for (size_t i = 0; i < arraysize(kCases); ++i) {
 447     GURL origin = GURL(kCases[i].origin).GetOrigin();
 448     base::FilePath file_name =
 449         base::FilePath().AppendASCII(kCases[i].file_name);
 450     base::FilePath journal_file_name =
 451         base::FilePath().AppendASCII(kCases[i].journal_file_name);
 452
 453     EXPECT_EQ(file_name,
 454               DOMStorageArea::DatabaseFileNameFromOrigin(origin));
 455     EXPECT_EQ(origin,
 456               DOMStorageArea::OriginFromDatabaseFileName(file_name));
 457     EXPECT_EQ(journal_file_name,
 458               DOMStorageDatabase::GetJournalFilePath(file_name));
 459   }
 460
 461   // Also test some DOMStorageDatabase::GetJournalFilePath cases here.
 462   base::FilePath parent = base::FilePath().AppendASCII("a").AppendASCII("b");
 463   EXPECT_EQ(
 464       parent.AppendASCII("file-journal"),
 465       DOMStorageDatabase::GetJournalFilePath(parent.AppendASCII("file")));
 466   EXPECT_EQ(
 467       base::FilePath().AppendASCII("-journal"),
 468       DOMStorageDatabase::GetJournalFilePath(base::FilePath()));
 469   EXPECT_EQ(
 470       base::FilePath().AppendASCII(".extensiononly-journal"),
 471       DOMStorageDatabase::GetJournalFilePath(
 472           base::FilePath().AppendASCII(".extensiononly")));
 473 }
 474
 475 TEST_F(DOMStorageAreaTest, RateLimiter) {
 476   // Limit to 1000 samples per second
 477   DOMStorageArea::RateLimiter rate_limiter(
 478       1000, base::TimeDelta::FromSeconds(1));
 479
 480   // No samples have been added so no time/delay should be needed.
 481   EXPECT_EQ(base::TimeDelta(),
 482             rate_limiter.ComputeTimeNeeded());
 483   EXPECT_EQ(base::TimeDelta(),
 484             rate_limiter.ComputeDelayNeeded(base::TimeDelta()));
 485   EXPECT_EQ(base::TimeDelta(),
 486             rate_limiter.ComputeDelayNeeded(base::TimeDelta::FromDays(1)));
 487
 488   // Add a seconds worth of samples.
 489   rate_limiter.add_samples(1000);
 490   EXPECT_EQ(base::TimeDelta::FromSeconds(1),
 491             rate_limiter.ComputeTimeNeeded());
 492   EXPECT_EQ(base::TimeDelta::FromSeconds(1),
 493             rate_limiter.ComputeDelayNeeded(base::TimeDelta()));
 494   EXPECT_EQ(base::TimeDelta(),
 495             rate_limiter.ComputeDelayNeeded(base::TimeDelta::FromSeconds(1)));
 496   EXPECT_EQ(base::TimeDelta::FromMilliseconds(250),
 497             rate_limiter.ComputeDelayNeeded(
 498                 base::TimeDelta::FromMilliseconds(750)));
 499   EXPECT_EQ(base::TimeDelta(),
 500             rate_limiter.ComputeDelayNeeded(
 501                 base::TimeDelta::FromDays(1)));
 502
 503   // And another half seconds worth.
 504   rate_limiter.add_samples(500);
 505   EXPECT_EQ(base::TimeDelta::FromMilliseconds(1500),
 506             rate_limiter.ComputeTimeNeeded());
 507   EXPECT_EQ(base::TimeDelta::FromMilliseconds(1500),
 508             rate_limiter.ComputeDelayNeeded(base::TimeDelta()));
 509   EXPECT_EQ(base::TimeDelta::FromMilliseconds(500),
 510             rate_limiter.ComputeDelayNeeded(base::TimeDelta::FromSeconds(1)));
 511   EXPECT_EQ(base::TimeDelta::FromMilliseconds(750),
 512             rate_limiter.ComputeDelayNeeded(
 513                 base::TimeDelta::FromMilliseconds(750)));
 514   EXPECT_EQ(base::TimeDelta(),
 515             rate_limiter.ComputeDelayNeeded(
 516                 base::TimeDelta::FromMilliseconds(1500)));
 517   EXPECT_EQ(base::TimeDelta(),
 518             rate_limiter.ComputeDelayNeeded(
 519                 base::TimeDelta::FromDays(1)));
 520 }
 521
 522 }  // namespace content