Use FSEvents for recursive file watch on Mac

base/files/file_path_watcher_browsertest.cc

 // 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.
 
 #include "base/files/file_path_watcher.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <aclapi.h>
 #elif defined(OS_POSIX)
@@ skipping 13 matching lines @@
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/run_loop.h"
 #include "base/stl_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/test/test_file_util.h"
 #include "base/test/test_timeouts.h"
 #include "base/threading/thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+#if defined(OS_MACOSX)
+#include "base/mac/mac_util.h"
+#endif
+
 namespace base {
 
 namespace {
 
 class TestDelegate;
 
+
+bool RecursiveWatchAvaiable() {
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+  // FSEvents isn't available on iOS and is broken on OSX 10.6 and earlier.
+  // See http://crbug.com/54822#c31
+  return mac::IsOSLionOrLater();
+#elif defined(OS_WIN) || defined(OS_LINUX)
+  return true;
+#else
+  return false;
+#endif
+}
+
 // Aggregates notifications from the test delegates and breaks the message loop
 // the test thread is waiting on once they all came in.
 class NotificationCollector
     : public base::RefCountedThreadSafe<NotificationCollector> {
  public:
   NotificationCollector()
       : loop_(base::MessageLoopProxy::current()) {}
 
   // Called from the file thread by the delegates.
   void OnChange(TestDelegate* delegate) {
@@ skipping 148 matching lines @@
 };
 
 bool FilePathWatcherTest::SetupWatch(const FilePath& target,
                                      FilePathWatcher* watcher,
                                      TestDelegateBase* delegate,
                                      bool recursive_watch) {
   base::WaitableEvent completion(false, false);
   bool result;
   file_thread_.message_loop_proxy()->PostTask(
       FROM_HERE,
-      base::Bind(SetupWatchCallback,
-                 target, watcher, delegate, recursive_watch, &result,
-                 &completion));
+      base::Bind(SetupWatchCallback, target, watcher, delegate, recursive_watch,
+                 &result, &completion));
   completion.Wait();
   return result;
 }
 
 // Basic test: Create the file and verify that we notice.
 TEST_F(FilePathWatcherTest, NewFile) {
   FilePathWatcher watcher;
   scoped_ptr<TestDelegate> delegate(new TestDelegate(collector()));
   ASSERT_TRUE(SetupWatch(test_file(), &watcher, delegate.get(), false));
 
@@ skipping 255 matching lines @@
   ASSERT_TRUE(WaitForEvents());
 
   // Move the parent directory.
   base::Move(dir, dest);
   VLOG(1) << "Waiting for directory move";
   ASSERT_TRUE(WaitForEvents());
   DeleteDelegateOnFileThread(file_delegate.release());
   DeleteDelegateOnFileThread(subdir_delegate.release());
 }
 
-#if defined(OS_WIN) || defined(OS_LINUX)
 TEST_F(FilePathWatcherTest, RecursiveWatch) {
   FilePathWatcher watcher;
   FilePath dir(temp_dir_.path().AppendASCII("dir"));
   scoped_ptr<TestDelegate> delegate(new TestDelegate(collector()));
-  ASSERT_TRUE(SetupWatch(dir, &watcher, delegate.get(), true));
+  bool setup_result = SetupWatch(dir, &watcher, delegate.get(), true);
+  if (!RecursiveWatchAvaiable()) {
+    ASSERT_FALSE(setup_result);
+    DeleteDelegateOnFileThread(delegate.release());
+    return;
+  }
+  ASSERT_TRUE(setup_result);
 
   // Main directory("dir") creation.
   ASSERT_TRUE(base::CreateDirectory(dir));
   ASSERT_TRUE(WaitForEvents());
 
   // Create "$dir/file1".
   FilePath file1(dir.AppendASCII("file1"));
   ASSERT_TRUE(WriteFile(file1, "content"));
   ASSERT_TRUE(WaitForEvents());
 
@@ skipping 27 matching lines @@
 
   // Delete "$dir/subdir/subdir_file1".
   ASSERT_TRUE(base::DeleteFile(subdir_file1, false));
   ASSERT_TRUE(WaitForEvents());
 
   // Delete "$dir/subdir/subdir_child_dir/child_dir_file1".
   ASSERT_TRUE(base::DeleteFile(child_dir_file1, false));
   ASSERT_TRUE(WaitForEvents());
   DeleteDelegateOnFileThread(delegate.release());
 }
-#else
-TEST_F(FilePathWatcherTest, RecursiveWatch) {
+
+#if defined(OS_POSIX)
+TEST_F(FilePathWatcherTest, RecursiveWithSymLink) {
+  if (!RecursiveWatchAvaiable())
+    return;
+
   FilePathWatcher watcher;
-  FilePath dir(temp_dir_.path().AppendASCII("dir"));
+  FilePath test_dir(temp_dir_.path().AppendASCII("test_dir"));
+  ASSERT_TRUE(base::CreateDirectory(test_dir));
+  FilePath symlink(test_dir.AppendASCII("symlink"));
   scoped_ptr<TestDelegate> delegate(new TestDelegate(collector()));
-  // Only Windows/Linux support recursive watching. Other implementations
-  // should simply fail.
-  ASSERT_FALSE(SetupWatch(dir, &watcher, delegate.get(), true));
+  ASSERT_TRUE(SetupWatch(symlink, &watcher, delegate.get(), true));
+
+  // Link creation.
+  FilePath target1(temp_dir_.path().AppendASCII("target1"));
+  ASSERT_TRUE(base::CreateSymbolicLink(target1, symlink));
+  ASSERT_TRUE(WaitForEvents());
+
+  // Target1 creation.
+  ASSERT_TRUE(base::CreateDirectory(target1));
+  ASSERT_TRUE(WaitForEvents());
+
+  // Create a file in target1.
+  FilePath target1_file(target1.AppendASCII("file"));
+  ASSERT_TRUE(WriteFile(target1_file, "content"));
+  ASSERT_TRUE(WaitForEvents());
+
+  // Link change.
+  FilePath target2(temp_dir_.path().AppendASCII("target2"));
+  ASSERT_TRUE(base::CreateDirectory(target2));
+  ASSERT_TRUE(base::DeleteFile(symlink, false));
+  ASSERT_TRUE(base::CreateSymbolicLink(target2, symlink));
+  ASSERT_TRUE(WaitForEvents());
+
+  // Create a file in target2.
+  FilePath target2_file(target2.AppendASCII("file"));
+  ASSERT_TRUE(WriteFile(target2_file, "content"));
+  ASSERT_TRUE(WaitForEvents());
+
   DeleteDelegateOnFileThread(delegate.release());
 }
-#endif
+#endif  // OS_POSIX
 
 TEST_F(FilePathWatcherTest, MoveChild) {
   FilePathWatcher file_watcher;
   FilePathWatcher subdir_watcher;
   FilePath source_dir(temp_dir_.path().AppendASCII("source"));
   FilePath source_subdir(source_dir.AppendASCII("subdir"));
   FilePath source_file(source_subdir.AppendASCII("file"));
   FilePath dest_dir(temp_dir_.path().AppendASCII("dest"));
   FilePath dest_subdir(dest_dir.AppendASCII("subdir"));
   FilePath dest_file(dest_subdir.AppendASCII("file"));
@@ skipping 268 matching lines @@
   ASSERT_TRUE(ChangeFilePermissions(test_dir1, Execute, false));
   ASSERT_TRUE(WaitForEvents());
   ASSERT_TRUE(ChangeFilePermissions(test_dir1, Execute, true));
   DeleteDelegateOnFileThread(delegate.release());
 }
 
 #endif  // OS_MACOSX
 }  // namespace
 
 }  // namespace base