Docserver: Factor SamplesModel out of SamplesDataSource

chrome/common/extensions/docs/server2/caching_file_system.py

 # 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.
 
 import posixpath
 import sys
 
 from file_system import FileSystem, StatInfo, FileNotFoundError
 from future import Future
-from path_util import IsDirectory
+from path_util import IsDirectory, ToDirectory
 from third_party.json_schema_compiler.memoize import memoize
 
 
 class CachingFileSystem(FileSystem):
   '''FileSystem which implements a caching layer on top of |file_system|. It's
   smart, using Stat() to decided whether to skip Read()ing from |file_system|,
   and only Stat()ing directories never files.
   '''
   def __init__(self, file_system, object_store_creator):
     self._file_system = file_system
@@ skipping 15 matching lines @@
   def Stat(self, path):
     return self.StatAsync(path).Get()
 
   def StatAsync(self, path):
     '''Stats the directory given, or if a file is given, stats the file's parent
     directory to get info about the file.
     '''
     # Always stat the parent directory, since it will have the stat of the child
     # anyway, and this gives us an entire directory's stat info at once.
     dir_path, file_path = posixpath.split(path)
-    if dir_path and not dir_path.endswith('/'):
-      dir_path += '/'
+    dir_path = ToDirectory(dir_path)
 
     def make_stat_info(dir_stat):
       '''Converts a dir stat into the correct resulting StatInfo; if the Stat
       was for a file, the StatInfo should just contain that file.
       '''
       if path == dir_path:
         return dir_stat
       # Was a file stat. Extract that file.
       file_version = dir_stat.child_versions.get(file_path)
       if file_version is None:
@@ skipping 68 matching lines @@
       return new_results
     # Read in the values that were uncached or old.
     return self._file_system.Read(set(paths) - set(fresh_data.iterkeys()),
                                   skip_not_found=skip_not_found).Then(next)
 
   def GetIdentity(self):
     return self._file_system.GetIdentity()
 
   def __repr__(self):
     return '%s of <%s>' % (type(self).__name__, repr(self._file_system))