[Telemetry] Add pyfakefs to telemetry/third_party

tools/telemetry/third_party/pyfakefs/pyfakefs/fake_filesystem_glob.py

Index: tools/telemetry/third_party/pyfakefs/pyfakefs/fake_filesystem_glob.py
diff --git a/tools/telemetry/third_party/pyfakefs/pyfakefs/fake_filesystem_glob.py b/tools/telemetry/third_party/pyfakefs/pyfakefs/fake_filesystem_glob.py
new file mode 100755
index 0000000000000000000000000000000000000000..db387df8b6f3488e8c912567aed2c280460ffb0b
--- /dev/null
+++ b/tools/telemetry/third_party/pyfakefs/pyfakefs/fake_filesystem_glob.py
@@ -0,0 +1,120 @@
+# Copyright 2009 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""A fake glob module implementation that uses fake_filesystem for unit tests.
+
+Includes:
+  FakeGlob: Uses a FakeFilesystem to provide a fake replacement for the
+    glob module.
+
+Usage:
+>>> import fake_filesystem
+>>> import fake_filesystem_glob
+>>> filesystem = fake_filesystem.FakeFilesystem()
+>>> glob_module = fake_filesystem_glob.FakeGlobModule(filesystem)
+
+>>> file = filesystem.CreateFile('new-file')
+>>> glob_module.glob('*')
+['new-file']
+>>> glob_module.glob('???-file')
+['new-file']
+"""
+
+import fnmatch
+import glob
+import os
+
+import fake_filesystem
+
+
+class FakeGlobModule(object):
+  """Uses a FakeFilesystem to provide a fake replacement for glob module."""
+
+  def __init__(self, filesystem):
+    """Construct fake glob module using the fake filesystem.
+
+    Args:
+      filesystem:  FakeFilesystem used to provide file system information
+    """
+    self._glob_module = glob
+    self._os_module = fake_filesystem.FakeOsModule(filesystem)
+    self._path_module = self._os_module.path
+
+  def glob(self, pathname):  # pylint: disable-msg=C6409
+    """Return a list of paths matching a pathname pattern.
+
+    The pattern may contain shell-style wildcards a la fnmatch.
+
+    Args:
+      pathname: the pattern with which to find a list of paths
+
+    Returns:
+      List of strings matching the glob pattern.
+    """
+    if not self.has_magic(pathname):
+      if self._path_module.exists(pathname):
+        return [pathname]
+      else:
+        return []
+
+    dirname, basename = self._path_module.split(pathname)
+
+    if not dirname:
+      return self.glob1(self._path_module.curdir, basename)
+    elif self.has_magic(dirname):
+      path_list = self.glob(dirname)
+    else:
+      path_list = [dirname]
+
+    if not self.has_magic(basename):
+      result = []
+      for dirname in path_list:
+        if basename or self._path_module.isdir(dirname):
+          name = self._path_module.join(dirname, basename)
+          if self._path_module.exists(name):
+            result.append(name)
+    else:
+      result = []
+      for dirname in path_list:
+        sublist = self.glob1(dirname, basename)
+        for name in sublist:
+          result.append(self._path_module.join(dirname, name))
+
+    return result
+
+  def glob1(self, dirname, pattern):  # pylint: disable-msg=C6409
+    if not dirname:
+      dirname = self._path_module.curdir
+    try:
+      names = self._os_module.listdir(dirname)
+    except os.error:
+      return []
+    if pattern[0] != '.':
+      names = filter(lambda x: x[0] != '.', names)
+    return fnmatch.filter(names, pattern)
+
+  def __getattr__(self, name):
+    """Forwards any non-faked calls to the standard glob module."""
+    return getattr(self._glob_module, name)
+
+
+def _RunDoctest():
+  # pylint: disable-msg=C6111,C6204,W0406
+  import doctest
+  import fake_filesystem_glob
+  return doctest.testmod(fake_filesystem_glob)
+
+
+if __name__ == '__main__':
+  _RunDoctest()