Refactor cache counting into a separate helper class

chrome/browser/browsing_data/cache_counter_browsertest.cc

 // Copyright (c) 2015 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.
 //
 // Note that this file only tests the basic behavior of the cache counter, as in
 // when it counts and when not, when result is nonzero and when not. It does not
 // test whether the result of the counting is correct. This is the
 // responsibility of a lower layer, and is tested in
 // DiskCacheBackendTest.CalculateSizeOfAllEntries in net_unittests.
 
@@ skipping 120 matching lines @@
       run_loop_->Quit();
   }
 
   // Callback from the counter.
   void CountingCallback(
       std::unique_ptr<browsing_data::BrowsingDataCounter::Result> result) {
     DCHECK_CURRENTLY_ON(BrowserThread::UI);
     finished_ = result->Finished();
 
     if (finished_) {
-      result_ =
-          static_cast<browsing_data::BrowsingDataCounter::FinishedResult*>(
-              result.get())
-              ->Value();
+      auto cache_result = static_cast<CacheCounter::CacheResult*>(result.get());
+      result_ = cache_result->cache_size();
+      is_upper_limit_ = cache_result->is_upper_limit();
     }
 
     if (run_loop_ && finished_)
       run_loop_->Quit();
   }
 
   browsing_data::BrowsingDataCounter::ResultInt GetResult() {
     DCHECK(finished_);
     return result_;
   }
 
+  bool IsUpperLimit() {
+    DCHECK(finished_);
+    return is_upper_limit_;
+  }
+
  private:
   enum CacheEntryCreationStep {
     GET_CACHE,
     CREATE_ENTRY,
     WRITE_DATA,
     DONE
   };
   CacheEntryCreationStep next_step_;
   content::StoragePartition* storage_partition_;
   disk_cache::Backend* backend_;
   disk_cache::Entry* entry_;
 
   std::unique_ptr<base::RunLoop> run_loop_;
 
   bool finished_;
   browsing_data::BrowsingDataCounter::ResultInt result_;
+  bool is_upper_limit_;
 };
 
 // Tests that for the empty cache, the result is zero.
 IN_PROC_BROWSER_TEST_F(CacheCounterTest, Empty) {
   Profile* profile = browser()->profile();
 
   CacheCounter counter(profile);
   counter.Init(
       profile->GetPrefs(),
       base::Bind(&CacheCounterTest::CountingCallback, base::Unretained(this)));
@@ skipping 63 matching lines @@
   Profile* profile = browser()->profile();
   CacheCounter counter(profile);
   counter.Init(
       profile->GetPrefs(),
       base::Bind(&CacheCounterTest::CountingCallback, base::Unretained(this)));
   counter.Restart();
 
   EXPECT_FALSE(counter.Pending());
 }
 
-// Tests that the counting is restarted when the time period changes. Currently,
-// the results should be the same for every period. This is because the counter
-// always counts the size of the entire cache, and it is up to the UI
-// to interpret it as exact value or upper bound.
+// Tests that the counting is restarted when the time period changes.
 IN_PROC_BROWSER_TEST_F(CacheCounterTest, PeriodChanged) {
   CreateCacheEntry();
 
   Profile* profile = browser()->profile();
   CacheCounter counter(profile);
   counter.Init(
       profile->GetPrefs(),
       base::Bind(&CacheCounterTest::CountingCallback, base::Unretained(this)));
 
   SetDeletionPeriodPref(browsing_data::LAST_HOUR);
   WaitForIOThread();
   browsing_data::BrowsingDataCounter::ResultInt result = GetResult();
+  EXPECT_FALSE(IsUpperLimit());
 
   SetDeletionPeriodPref(browsing_data::LAST_DAY);
   WaitForIOThread();
   EXPECT_EQ(result, GetResult());
+  EXPECT_FALSE(IsUpperLimit());
 
   SetDeletionPeriodPref(browsing_data::LAST_WEEK);
   WaitForIOThread();
   EXPECT_EQ(result, GetResult());
+  EXPECT_FALSE(IsUpperLimit());
 
   SetDeletionPeriodPref(browsing_data::FOUR_WEEKS);
   WaitForIOThread();
   EXPECT_EQ(result, GetResult());
+  EXPECT_FALSE(IsUpperLimit());
 
   SetDeletionPeriodPref(browsing_data::ALL_TIME);
   WaitForIOThread();
   EXPECT_EQ(result, GetResult());
+  EXPECT_FALSE(IsUpperLimit());
+}
+
+// Tests the cache size is estimated if the timeout runs out.
+IN_PROC_BROWSER_TEST_F(CacheCounterTest, Timeout) {
+  CreateCacheEntry();
+
+  Profile* profile = browser()->profile();
+  CacheCounter counter(profile);
+  counter.SetTimeout(base::TimeDelta());
+  counter.Init(
+      profile->GetPrefs(),
+      base::Bind(&CacheCounterTest::CountingCallback, base::Unretained(this)));
+
+  SetDeletionPeriodPref(browsing_data::LAST_DAY);
+  WaitForIOThread();
+  EXPECT_GT(GetResult(), 0);
+  EXPECT_TRUE(IsUpperLimit());
+
+  // Even with a timeout of 0, ALL_TIME shouldn't be returned as upper limit.
+  SetDeletionPeriodPref(browsing_data::ALL_TIME);
+  WaitForIOThread();
+  EXPECT_GT(GetResult(), 0);
+  EXPECT_FALSE(IsUpperLimit());
 }
 
 }  // namespace