**STILLBAKING** Decouple disk cache tests from backends.

net/disk_cache/disk_cache_test.h

+// Copyright (c) 2012 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 NET_DISK_CACHE_DISK_CACHE_TEST_H_
+#define NET_DISK_CACHE_DISK_CACHE_TEST_H_
+
+#include "base/basictypes.h"
+#include "base/files/file_path.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/threading/thread.h"
+#include "net/base/cache_type.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/platform_test.h"
+
+namespace base {
+class MessageLoopProxy;
+}  // namespace base
+
+namespace net {
+class IOBuffer;
+}  // namespace net
+
+namespace disk_cache {
+
+class Backend;
+class BackendImpl;
+class Entry;
+class MemBackendImpl;
+class SimpleBackendImpl;
+
+class BackendTestTraits {
+ public:
+  class CreateBackendExtraData {
+   protected:
+    ~CreateBackendExtraData();
+  };
+
+  BackendTestTraits() {}
+  virtual ~BackendTestTraits() {}
+
+  virtual Backend* CreateBackend(const CreateBackendExtraData* extra_data,
+                                 const base::FilePath& cache_path,
+                                 int max_size,
+                                 base::MessageLoopProxy* task_runner) const = 0;
+
+  virtual bool UsesCacheThread() const = 0;
+
+  // Backend specific quirks that tests might want to respect:
+  virtual bool WritesUpdateLastUsed() const;
+  virtual bool ReadsUpdateLastUsed() const;
+  virtual int SparseRoundingInterval() const;
+  virtual bool EntryCountIncludesSparseRanges() const;
+  virtual bool ImplementsCouldBeSparse() const;
+  virtual bool DoomedSparseEntriesIOWorks() const;
+  virtual bool EnumerationsAreLexicographicByKey() const;
+
+  // Events
+  virtual void PreTearDown() const {}
+  virtual void PostTearDown() const {}
+
+
+  // Helpers
+  virtual bool SetMaxSize(Backend* backend, int size) const = 0;
+  virtual void FlushQueueForTest(Backend* backend) const {}
+  virtual void AddDelay() const;
+};
+
+// Provides basic support for cache related tests.
+class DiskCacheTest : public PlatformTest,
+                      public ::testing::WithParamInterface<const BackendTestTraits*>
+{
+ public:
+  void InitCache() { InitCacheWithExtraData(NULL); }
+
+  // Utility methods to access the cache and wait for each operation to finish.
+  int OpenEntry(const std::string& key, disk_cache::Entry** entry);
+  int CreateEntry(const std::string& key, disk_cache::Entry** entry);
+  int DoomEntry(const std::string& key);
+  int DoomAllEntries();
+  int DoomEntriesBetween(const base::Time initial_time,
+                         const base::Time end_time);
+  int DoomEntriesSince(const base::Time initial_time);
+  int OpenNextEntry(void** iter, disk_cache::Entry** next_entry);
+  int ReadData(disk_cache::Entry* entry, int index, int offset,
+               net::IOBuffer* buf, int len);
+  int WriteData(disk_cache::Entry* entry, int index, int offset,
+                net::IOBuffer* buf, int len, bool truncate);
+  int ReadSparseData(disk_cache::Entry* entry, int64 offset, net::IOBuffer* buf,
+                     int len);
+  int WriteSparseData(disk_cache::Entry* entry, int64 offset,
+                      net::IOBuffer* buf, int len);
+
+  const base::FilePath& cache_path() const { return temp_dir_.path(); }
+  disk_cache::Backend* cache() { return cache_.get(); }
+
+  // Makes sure that some time passes before continuing the test. Time::Now()
+  // before and after this method will not be the same.
+  void AddDelay();
+
+  void FlushQueueForTest();
+
+  void SetMaxSize(int max_size);
+
+  // Copies a set of cache files from the data folder to the test folder.
+  bool CopyTestCache(const std::string& name);
+
+ protected:
+  DiskCacheTest();
+  virtual ~DiskCacheTest();
+
+  // Do not call this in a test that may run on multiple backends.
+  void InitCacheWithExtraData(const BackendTestTraits::CreateBackendExtraData* extra_data);
+  
+  void DeleteCache() { cache_.reset(); }
+
+  void CreateBackend(uint32 flags, base::Thread* thread);
+
+  // Deletes the contents of |cache_path_|.
+  bool CleanupCacheDir();
+
+  void UseCurrentThread() { use_current_thread_ = true; }
+
+  // TODO(implement)
+  void DisableIntegrityCheck() {}
+
+
+  base::MessageLoopProxy* GetCacheThread();
+
+
+  // From PlatformTest:
+  virtual void TearDown() OVERRIDE;
+
+  const BackendTestTraits* traits() const { return traits_; }
+
+ protected:
+
+ private:
+  bool use_current_thread_;
+  int max_size_;
+
+  scoped_ptr<disk_cache::Backend> cache_;
+
+  base::ScopedTempDir temp_dir_;
+  scoped_ptr<base::MessageLoop> message_loop_;
+
+  const BackendTestTraits* traits_;
+
+  base::Thread cache_thread_;
+  DISALLOW_COPY_AND_ASSIGN(DiskCacheTest);
+};
+
+}  // namespace disk_cache
+
+#endif  // NET_DISK_CACHE_DISK_CACHE_TEST_H_