[Sync] Make syncer commands avoid posting tasks on threads with no work to do

chrome/browser/sync/test/engine/syncer_command_test.h

 // 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.
 
 #ifndef CHROME_BROWSER_SYNC_TEST_ENGINE_SYNCER_COMMAND_TEST_H_
 #define CHROME_BROWSER_SYNC_TEST_ENGINE_SYNCER_COMMAND_TEST_H_
 #pragma once
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
 #include "base/message_loop.h"
+#include "chrome/browser/sync/engine/model_changing_syncer_command.h"
 #include "chrome/browser/sync/engine/model_safe_worker.h"
 #include "chrome/browser/sync/sessions/debug_info_getter.h"
 #include "chrome/browser/sync/sessions/sync_session.h"
 #include "chrome/browser/sync/sessions/sync_session_context.h"
 #include "chrome/browser/sync/test/engine/mock_connection_manager.h"
+#include "chrome/browser/sync/test/engine/fake_model_worker.h"
 #include "chrome/browser/sync/test/engine/test_directory_setter_upper.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
 using ::testing::NiceMock;
 
 namespace browser_sync {
 
 class MockDebugInfoGetter : public browser_sync::sessions::DebugInfoGetter {
  public:
@@ skipping 56 matching lines @@
  protected:
   SyncerCommandTestWithParam() : syncdb_(new TestDirectorySetterUpper()) {}
 
   explicit SyncerCommandTestWithParam(UseMockDirectory use_mock)
       : syncdb_(new MockDirectorySetterUpper()) {}
 
   virtual ~SyncerCommandTestWithParam() {}
   virtual void SetUp() {
     syncdb_->SetUp();
     ResetContext();
+    // The session always expects there to be a passive worker.
+    workers()->push_back(
+        make_scoped_refptr(new FakeModelWorker(GROUP_PASSIVE)));
   }
   virtual void TearDown() {
     syncdb_->TearDown();
   }
 
   TestDirectorySetterUpper* syncdb() { return syncdb_.get(); }
   sessions::SyncSessionContext* context() const { return context_.get(); }
   sessions::SyncSession::Delegate* delegate() { return this; }
   ModelSafeWorkerRegistrar* registrar() { return this; }
 
@@ skipping 44 matching lines @@
   ModelSafeRoutingInfo* mutable_routing_info() { return &routing_info_; }
 
   MockConnectionManager* mock_server() {
     return mock_server_.get();
   }
 
   MockDebugInfoGetter* mock_debug_info_getter() {
     return &mock_debug_info_getter_;
   }
 
+  // Helper functions to check command.GetGroupsToChange().
+
+  void ExpectNoGroupsToChange(const ModelChangingSyncerCommand& command) {
+    EXPECT_TRUE(command.GetGroupsToChangeForTest(*session()).empty());
+  }
+
+  void ExpectGroupToChange(
+      const ModelChangingSyncerCommand& command, ModelSafeGroup group) {
+    std::set<ModelSafeGroup> expected_groups_to_change;
+    expected_groups_to_change.insert(group);
+    EXPECT_EQ(expected_groups_to_change,
+              command.GetGroupsToChangeForTest(*session()));
+  }
+
+  void ExpectGroupsToChange(
+      const ModelChangingSyncerCommand& command,
+      ModelSafeGroup group1, ModelSafeGroup group2) {
+    std::set<ModelSafeGroup> expected_groups_to_change;
+    expected_groups_to_change.insert(group1);
+    expected_groups_to_change.insert(group2);
+    EXPECT_EQ(expected_groups_to_change,
+              command.GetGroupsToChangeForTest(*session()));
+  }
+
+  void ExpectGroupsToChange(
+      const ModelChangingSyncerCommand& command,
+      ModelSafeGroup group1, ModelSafeGroup group2, ModelSafeGroup group3) {
+    std::set<ModelSafeGroup> expected_groups_to_change;
+    expected_groups_to_change.insert(group1);
+    expected_groups_to_change.insert(group2);
+    expected_groups_to_change.insert(group3);
+    EXPECT_EQ(expected_groups_to_change,
+              command.GetGroupsToChangeForTest(*session()));
+  }
+
  private:
   MessageLoop message_loop_;
   scoped_ptr<TestDirectorySetterUpper> syncdb_;
   scoped_ptr<sessions::SyncSessionContext> context_;
   scoped_ptr<MockConnectionManager> mock_server_;
   scoped_ptr<sessions::SyncSession> session_;
   std::vector<scoped_refptr<ModelSafeWorker> > workers_;
   ModelSafeRoutingInfo routing_info_;
   NiceMock<MockDebugInfoGetter> mock_debug_info_getter_;
   DISALLOW_COPY_AND_ASSIGN(SyncerCommandTestWithParam);
 };
 
 class SyncerCommandTest : public SyncerCommandTestWithParam<void*> {};
 
 class MockDirectorySyncerCommandTest
     : public SyncerCommandTestWithParam<void*> {
  public:
   MockDirectorySyncerCommandTest()
       : SyncerCommandTestWithParam<void*>(
           SyncerCommandTestWithParam<void*>::USE_MOCK_DIRECTORY) {}
   MockDirectorySetterUpper::MockDirectory* mock_directory() {
     return static_cast<MockDirectorySetterUpper*>(syncdb())->directory();
   }
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_TEST_ENGINE_SYNCER_COMMAND_TEST_H_