Use SNAPSHOT sync mode for LocalSync

chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc

Index: chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
diff --git a/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc b/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
index a1ede5ae806c2a7fc6ff060194af0160c728e56b..1d3b36064099dca3f9ba84c637ab7001cfc009da 100644
--- a/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
+++ b/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
@@ -26,6 +26,7 @@
 #include "webkit/browser/fileapi/file_system_context.h"
 #include "webkit/browser/fileapi/file_system_operation_runner.h"
 #include "webkit/browser/fileapi/isolated_context.h"
+#include "webkit/common/blob/scoped_file.h"
 
 #define FPL FILE_PATH_LITERAL
 
@@ -60,6 +61,7 @@ class LocalFileSyncContextTest : public testing::Test {
 
   virtual void SetUp() OVERRIDE {
     RegisterSyncableFileSystem();
+    ASSERT_TRUE(dir_.CreateUniqueTempDir());
 
     ui_task_runner_ = base::MessageLoop::current()->message_loop_proxy();
     io_task_runner_ = BrowserThread::GetMessageLoopProxyForThread(
@@ -74,8 +76,10 @@ class LocalFileSyncContextTest : public testing::Test {
 
   void StartPrepareForSync(FileSystemContext* file_system_context,
                            const FileSystemURL& url,
+                           LocalFileSyncContext::SyncMode sync_mode,
                            SyncFileMetadata* metadata,
-                           FileChangeList* changes) {
+                           FileChangeList* changes,
+                           webkit_blob::ScopedFile* snapshot) {
     ASSERT_TRUE(changes != NULL);
     ASSERT_FALSE(has_inflight_prepare_for_sync_);
     status_ = SYNC_STATUS_UNKNOWN;
@@ -83,39 +87,49 @@ class LocalFileSyncContextTest : public testing::Test {
     sync_context_->PrepareForSync(
         file_system_context,
         url,
-        LocalFileSyncContext::SYNC_EXCLUSIVE,
+        sync_mode,
         base::Bind(&LocalFileSyncContextTest::DidPrepareForSync,
-                   base::Unretained(this), metadata, changes));
+                   base::Unretained(this), metadata, changes, snapshot));
   }
 
   SyncStatusCode PrepareForSync(FileSystemContext* file_system_context,
                                 const FileSystemURL& url,
+                                LocalFileSyncContext::SyncMode sync_mode,
                                 SyncFileMetadata* metadata,
-                                FileChangeList* changes) {
-    StartPrepareForSync(file_system_context, url, metadata, changes);
+                                FileChangeList* changes,
+                                webkit_blob::ScopedFile* snapshot) {
+    StartPrepareForSync(file_system_context, url, sync_mode,
+                        metadata, changes, snapshot);
     base::MessageLoop::current()->Run();
     return status_;
   }
 
-  base::Closure GetPrepareForSyncClosure(FileSystemContext* file_system_context,
-                                         const FileSystemURL& url,
-                                         SyncFileMetadata* metadata,
-                                         FileChangeList* changes) {
+  base::Closure GetPrepareForSyncClosure(
+      FileSystemContext* file_system_context,
+      const FileSystemURL& url,
+      LocalFileSyncContext::SyncMode sync_mode,
+      SyncFileMetadata* metadata,
+      FileChangeList* changes,
+      webkit_blob::ScopedFile* snapshot) {
     return base::Bind(&LocalFileSyncContextTest::StartPrepareForSync,
                       base::Unretained(this),
                       base::Unretained(file_system_context),
-                      url, metadata, changes);
+                      url, sync_mode, metadata, changes, snapshot);
   }
 
   void DidPrepareForSync(SyncFileMetadata* metadata_out,
                          FileChangeList* changes_out,
+                         webkit_blob::ScopedFile* snapshot_out,
                          SyncStatusCode status,
-                         const LocalFileSyncInfo& sync_file_info) {
+                         const LocalFileSyncInfo& sync_file_info,
+                         scoped_ptr<webkit_blob::ScopedFile> snapshot) {
     ASSERT_TRUE(ui_task_runner_->RunsTasksOnCurrentThread());
     has_inflight_prepare_for_sync_ = false;
     status_ = status;
     *metadata_out = sync_file_info.metadata;
     *changes_out = sync_file_info.changes;
+    if (snapshot_out && snapshot)
+      *snapshot_out = snapshot->Pass();
     base::MessageLoop::current()->Quit();
   }
 
@@ -131,7 +145,9 @@ class LocalFileSyncContextTest : public testing::Test {
     SyncFileMetadata metadata;
     FileChangeList changes;
     EXPECT_EQ(SYNC_STATUS_OK,
-              PrepareForSync(file_system_context, url, &metadata, &changes));
+              PrepareForSync(file_system_context, url,
+                             LocalFileSyncContext::SYNC_EXCLUSIVE,
+                             &metadata, &changes, NULL));
     EXPECT_EQ(expected_file_type, metadata.file_type);
 
     status_ = SYNC_STATUS_UNKNOWN;
@@ -206,7 +222,7 @@ class LocalFileSyncContextTest : public testing::Test {
                                          file_task_runner_.get());
     file_system.SetUp();
     sync_context_ = new LocalFileSyncContext(
-        ui_task_runner_.get(), io_task_runner_.get());
+        dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
     ASSERT_EQ(SYNC_STATUS_OK,
               file_system.MaybeInitializeFileSystemContext(
                   sync_context_.get()));
@@ -219,7 +235,7 @@ class LocalFileSyncContextTest : public testing::Test {
     FileChangeList changes;
     EXPECT_EQ(SYNC_STATUS_OK,
               PrepareForSync(file_system.file_system_context(), kFile,
-                             &metadata, &changes));
+                             sync_mode, &metadata, &changes, NULL));
     EXPECT_EQ(1U, changes.size());
     EXPECT_TRUE(changes.list().back().IsFile());
     EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
@@ -249,8 +265,73 @@ class LocalFileSyncContextTest : public testing::Test {
     file_system.TearDown();
   }
 
+  void PrepareForSync_WriteDuringSync(
+      LocalFileSyncContext::SyncMode sync_mode) {
+    CannedSyncableFileSystem file_system(GURL(kOrigin1),
+                                         io_task_runner_.get(),
+                                         file_task_runner_.get());
+    file_system.SetUp();
+    sync_context_ = new LocalFileSyncContext(
+        dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
+    ASSERT_EQ(SYNC_STATUS_OK,
+              file_system.MaybeInitializeFileSystemContext(
+                  sync_context_.get()));
+    ASSERT_EQ(base::PLATFORM_FILE_OK, file_system.OpenFileSystem());
+
+    const FileSystemURL kFile(file_system.URL("file"));
+    EXPECT_EQ(base::PLATFORM_FILE_OK, file_system.CreateFile(kFile));
+
+    SyncFileMetadata metadata;
+    FileChangeList changes;
+    webkit_blob::ScopedFile snapshot;
+    EXPECT_EQ(SYNC_STATUS_OK,
+              PrepareForSync(file_system.file_system_context(), kFile,
+                             sync_mode, &metadata, &changes, &snapshot));
+    EXPECT_EQ(1U, changes.size());
+    EXPECT_TRUE(changes.list().back().IsFile());
+    EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
+
+    EXPECT_EQ(sync_mode == LocalFileSyncContext::SYNC_SNAPSHOT,
+              !snapshot.path().empty());
+
+    // Tracker keeps same set of changes.
+    file_system.GetChangesForURLInTracker(kFile, &changes);
+    EXPECT_EQ(1U, changes.size());
+    EXPECT_TRUE(changes.list().back().IsFile());
+    EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
+
+    StartModifyFileOnIOThread(&file_system, kFile);
+
+    if (sync_mode == LocalFileSyncContext::SYNC_SNAPSHOT) {
+      // Write should succeed.
+      EXPECT_EQ(base::PLATFORM_FILE_OK, WaitUntilModifyFileIsDone());
+    } else {
+      base::MessageLoop::current()->RunUntilIdle();
+      EXPECT_FALSE(async_modify_finished_);
+    }
+
+    SimulateFinishSync(file_system.file_system_context(), kFile,
+                       SYNC_STATUS_OK);
+
+    EXPECT_EQ(base::PLATFORM_FILE_OK, WaitUntilModifyFileIsDone());
+
+    // Sync succeeded, but the other change that was made during or
+    // after sync is recorded.
+    file_system.GetChangesForURLInTracker(kFile, &changes);
+    EXPECT_EQ(1U, changes.size());
+    EXPECT_TRUE(changes.list().back().IsFile());
+    EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
+
+    sync_context_->ShutdownOnUIThread();
+    sync_context_ = NULL;
+
+    file_system.TearDown();
+  }
+
   ScopedEnableSyncFSDirectoryOperation enable_directory_operation_;
 
+  base::ScopedTempDir dir_;
+
   // These need to remain until the very end.
   content::TestBrowserThreadBundle thread_bundle_;
 
@@ -267,8 +348,9 @@ class LocalFileSyncContextTest : public testing::Test {
 };
 
 TEST_F(LocalFileSyncContextTest, ConstructAndDestruct) {
-  sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+  sync_context_ =
+      new LocalFileSyncContext(
+          dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
   sync_context_->ShutdownOnUIThread();
 }
 
@@ -279,7 +361,7 @@ TEST_F(LocalFileSyncContextTest, InitializeFileSystemContext) {
   file_system.SetUp();
 
   sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+      dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
 
   // Initializes file_system using |sync_context_|.
   EXPECT_EQ(SYNC_STATUS_OK,
@@ -324,7 +406,7 @@ TEST_F(LocalFileSyncContextTest, MultipleFileSystemContexts) {
   file_system2.SetUp();
 
   sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+      dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
 
   // Initializes file_system1 and file_system2.
   EXPECT_EQ(SYNC_STATUS_OK,
@@ -371,7 +453,8 @@ TEST_F(LocalFileSyncContextTest, MultipleFileSystemContexts) {
   FileChangeList changes;
   EXPECT_EQ(SYNC_STATUS_OK,
             PrepareForSync(file_system1.file_system_context(), kURL1,
-                           &metadata, &changes));
+                           LocalFileSyncContext::SYNC_EXCLUSIVE,
+                           &metadata, &changes, NULL));
   EXPECT_EQ(1U, changes.size());
   EXPECT_TRUE(changes.list().back().IsFile());
   EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
@@ -381,7 +464,8 @@ TEST_F(LocalFileSyncContextTest, MultipleFileSystemContexts) {
   changes.clear();
   EXPECT_EQ(SYNC_STATUS_OK,
             PrepareForSync(file_system2.file_system_context(), kURL2,
-                           &metadata, &changes));
+                           LocalFileSyncContext::SYNC_EXCLUSIVE,
+                           &metadata, &changes, NULL));
   EXPECT_EQ(1U, changes.size());
   EXPECT_FALSE(changes.list().back().IsFile());
   EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
@@ -415,6 +499,14 @@ TEST_F(LocalFileSyncContextTest, PrepareSync_SyncFailure_Snapshot) {
                        SYNC_STATUS_FAILED);
 }
 
+TEST_F(LocalFileSyncContextTest, PrepareSync_WriteDuringSync_Exclusive) {
+  PrepareForSync_WriteDuringSync(LocalFileSyncContext::SYNC_EXCLUSIVE);
+}
+
+TEST_F(LocalFileSyncContextTest, PrepareSync_WriteDuringSync_Snapshot) {
+  PrepareForSync_WriteDuringSync(LocalFileSyncContext::SYNC_SNAPSHOT);
+}
+
 // LocalFileSyncContextTest.PrepareSyncWhileWriting is flaky on android.
 // http://crbug.com/239793
 #if defined(OS_ANDROID)
@@ -428,7 +520,7 @@ TEST_F(LocalFileSyncContextTest, MAYBE_PrepareSyncWhileWriting) {
                                        file_task_runner_.get());
   file_system.SetUp();
   sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+      dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
   EXPECT_EQ(SYNC_STATUS_OK,
             file_system.MaybeInitializeFileSystemContext(sync_context_.get()));
 
@@ -447,8 +539,9 @@ TEST_F(LocalFileSyncContextTest, MAYBE_PrepareSyncWhileWriting) {
   metadata.file_type = SYNC_FILE_TYPE_UNKNOWN;
   FileChangeList changes;
   EXPECT_EQ(SYNC_STATUS_FILE_BUSY,
-            PrepareForSync(file_system.file_system_context(),
-                           kURL1, &metadata, &changes));
+            PrepareForSync(file_system.file_system_context(), kURL1,
+                           LocalFileSyncContext::SYNC_EXCLUSIVE,
+                           &metadata, &changes, NULL));
   EXPECT_EQ(SYNC_FILE_TYPE_FILE, metadata.file_type);
 
   // Register PrepareForSync method to be invoked when kURL1 becomes
@@ -457,8 +550,9 @@ TEST_F(LocalFileSyncContextTest, MAYBE_PrepareSyncWhileWriting) {
   metadata.file_type = SYNC_FILE_TYPE_UNKNOWN;
   changes.clear();
   sync_context_->RegisterURLForWaitingSync(
-      kURL1, GetPrepareForSyncClosure(file_system.file_system_context(),
-                                      kURL1, &metadata, &changes));
+      kURL1, GetPrepareForSyncClosure(file_system.file_system_context(), kURL1,
+                                      LocalFileSyncContext::SYNC_EXCLUSIVE,
+                                      &metadata, &changes, NULL));
 
   // Wait for the completion.
   EXPECT_EQ(base::PLATFORM_FILE_OK, WaitUntilModifyFileIsDone());
@@ -488,7 +582,7 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForDeletion) {
   file_system.SetUp();
 
   sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+      dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
   ASSERT_EQ(SYNC_STATUS_OK,
             file_system.MaybeInitializeFileSystemContext(sync_context_.get()));
   ASSERT_EQ(base::PLATFORM_FILE_OK, file_system.OpenFileSystem());
@@ -577,7 +671,7 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForAddOrUpdate) {
   file_system.SetUp();
 
   sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+      dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
   ASSERT_EQ(SYNC_STATUS_OK,
             file_system.MaybeInitializeFileSystemContext(sync_context_.get()));
   ASSERT_EQ(base::PLATFORM_FILE_OK, file_system.OpenFileSystem());
@@ -726,7 +820,7 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForAddOrUpdate_NoParent) {
   file_system.SetUp();
 
   sync_context_ = new LocalFileSyncContext(
-      ui_task_runner_.get(), io_task_runner_.get());
+      dir_.path(), ui_task_runner_.get(), io_task_runner_.get());
   ASSERT_EQ(SYNC_STATUS_OK,
             file_system.MaybeInitializeFileSystemContext(sync_context_.get()));
   ASSERT_EQ(base::PLATFORM_FILE_OK, file_system.OpenFileSystem());