1# Copyright 2014 The Chromium Authors. All rights reserved.
2# Use of this source code is governed by a BSD-style license that can be
3# found in the LICENSE file.
4
5import collections
6import os
7
8
9class PathSet(collections.MutableSet):
10  """A set of paths.
11
12  All mutation methods can take both directories or individual files, but the
13  iterator yields the individual files. All paths are automatically normalized.
14  """
15  def __init__(self, iterable=None):
16    self._paths = set()
17    if iterable:
18      self |= iterable
19
20  def __contains__(self, path):
21    return os.path.realpath(path) in self._paths
22
23  def __iter__(self):
24    return iter(self._paths)
25
26  def __len__(self):
27    return len(self._paths)
28
29  def add(self, path):
30    path = os.path.realpath(path)
31    if os.path.isfile(path):
32      self._paths.add(path)
33    for root, _, files in os.walk(path):
34      for basename in files:
35        file_path = os.path.join(root, basename)
36        if os.path.isfile(file_path):
37          self._paths.add(file_path)
38
39  def discard(self, path):
40    path = os.path.realpath(path)
41    self._paths.discard(path)
42    for root, _, files in os.walk(path):
43      for basename in files:
44        self._paths.discard(os.path.join(root, basename))
45