[Telemetry] Add pyfakefs to telemetry/third_party

tools/telemetry/third_party/pyfakefs/pyfakefs/fake_tempfile.py

+# Copyright 2010 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.
+
+"""Fake tempfile module.
+
+Fake implementation of the python2.4.1 tempfile built-in module that works with
+a FakeFilesystem object.
+"""
+#pylint: disable-all
+
+import errno
+import logging
+import os
+import stat
+import tempfile
+
+import fake_filesystem
+
+try:
+  import StringIO as io  # pylint: disable-msg=C6204
+except ImportError:
+  import io  # pylint: disable-msg=C6204
+
+
+class FakeTempfileModule(object):
+  """Uses a FakeFilesystem to provide a mock for the tempfile 2.4.1 module.
+
+  Common usage:
+  filesystem = fake_filesystem.FakeFilesystem()
+  my_tempfile_module = mock_tempfile.FakeTempfileModule(filesystem)
+
+  See also: default keyword arguments for Dependency Injection on
+  http://go/tott-episode-12
+  """
+
+  def __init__(self, filesystem):
+    self._filesystem = filesystem
+    self._tempfile = tempfile
+    self.tempdir = None  # initialized by mktemp(), others
+    self._temp_prefix = 'tmp'
+    self._mktemp_retvals = []
+
+  # pylint: disable-msg=W0622
+  def _TempFilename(self, suffix='', prefix=None, dir=None):
+    """Create a temporary filename that does not exist.
+
+    This is a re-implementation of how tempfile creates random filenames,
+    and is probably different.
+
+    Does not modify self._filesystem, that's your job.
+
+    Output: self.tempdir is initialized if unset
+    Args:
+      suffix: filename suffix
+      prefix: filename prefix
+      dir: dir to put filename in
+    Returns:
+      string, temp filename that does not exist
+    """
+    if dir is None:
+      dir = self._filesystem.JoinPaths(self._filesystem.root.name, 'tmp')
+    filename = None
+    if prefix is None:
+      prefix = self._temp_prefix
+    while not filename or self._filesystem.Exists(filename):
+      # pylint: disable-msg=W0212
+      filename = self._filesystem.JoinPaths(dir, '%s%s%s' % (
+          prefix,
+          next(self._tempfile._RandomNameSequence()),
+          suffix))
+    return filename
+
+  # pylint: disable-msg=W0622,W0613
+  def TemporaryFile(self, mode='w+b', bufsize=-1,
+                    suffix='', prefix=None, dir=None):
+    """Return a file-like object deleted on close().
+
+    Python 2.4.1 tempfile.TemporaryFile.__doc__ =
+    >Return a file (or file-like) object that can be used as a temporary
+    >storage area. The file is created using mkstemp. It will be destroyed as
+    >soon as it is closed (including an implicit close when the object is
+    >garbage collected). Under Unix, the directory entry for the file is
+    >removed immediately after the file is created. Other platforms do not
+    >support this; your code should not rely on a temporary file created using
+    >this function having or not having a visible name in the file system.
+    >
+    >The mode parameter defaults to 'w+b' so that the file created can be read
+    >and written without being closed. Binary mode is used so that it behaves
+    >consistently on all platforms without regard for the data that is stored.
+    >bufsize defaults to -1, meaning that the operating system default is used.
+    >
+    >The dir, prefix and suffix parameters are passed to mkstemp()
+
+    Args:
+      mode: optional string, see above
+      bufsize: optional int, see above
+      suffix: optional string, see above
+      prefix: optional string, see above
+      dir: optional string, see above
+    Returns:
+      a file-like object.
+    """
+    # pylint: disable-msg=C6002
+    # TODO: prefix, suffix, bufsize, dir, mode unused?
+    # cannot be cStringIO due to .name requirement below
+    retval = io.StringIO()
+    retval.name = '<fdopen>'  # as seen on 2.4.3
+    return retval
+
+  # pylint: disable-msg=W0622,W0613
+  def NamedTemporaryFile(self, mode='w+b', bufsize=-1,
+                         suffix='', prefix=None, dir=None, delete=True):
+    """Return a file-like object with name that is deleted on close().
+
+    Python 2.4.1 tempfile.NamedTemporaryFile.__doc__ =
+    >This function operates exactly as TemporaryFile() does, except that
+    >the file is guaranteed to have a visible name in the file system. That
+    >name can be retrieved from the name member of the file object.
+
+    Args:
+      mode: optional string, see above
+      bufsize: optional int, see above
+      suffix: optional string, see above
+      prefix: optional string, see above
+      dir: optional string, see above
+      delete: optional bool, see above
+    Returns:
+      a file-like object including obj.name
+    """
+    # pylint: disable-msg=C6002
+    # TODO: bufsiz unused?
+    temp = self.mkstemp(suffix=suffix, prefix=prefix, dir=dir)
+    filename = temp[1]
+    mock_open = fake_filesystem.FakeFileOpen(
+        self._filesystem, delete_on_close=delete)
+    obj = mock_open(filename, mode)
+    obj.name = filename
+    return obj
+
+  # pylint: disable-msg=C6409
+  def mkstemp(self, suffix='', prefix=None, dir=None, text=False):
+    """Create temp file, returning a 2-tuple: (9999, filename).
+
+    Important: Returns 9999 instead of a real file descriptor!
+
+    Python 2.4.1 tempfile.mkstemp.__doc__ =
+    >mkstemp([suffix, [prefix, [dir, [text]]]])
+    >
+    >User-callable function to create and return a unique temporary file.
+    >The return value is a pair (fd, name) where fd is the file descriptor
+    >returned by os.open, and name is the filename.
+    >
+    >...[snip args]...
+    >
+    >The file is readable and writable only by the creating user ID.
+    >If the operating system uses permission bits to indicate whether
+    >a file is executable, the file is executable by no one. The file
+    >descriptor is not inherited by children of this process.
+    >
+    >Caller is responsible for deleting the file when done with it.
+
+    NOTE: if dir is unspecified, this call creates a directory.
+
+    Output: self.tempdir is initialized if unset
+    Args:
+      suffix: optional string, filename suffix
+      prefix: optional string, filename prefix
+      dir: optional string, directory for temp file; must exist before call
+      text: optional boolean, True = open file in text mode.
+          default False = open file in binary mode.
+    Returns:
+      2-tuple containing
+      [0] = int, file descriptor number for the file object
+      [1] = string, absolute pathname of a file
+    Raises:
+      OSError: when dir= is specified but does not exist
+    """
+    # pylint: disable-msg=C6002
+    # TODO: optional boolean text is unused?
+    # default dir affected by "global"
+    filename = self._TempEntryname(suffix, prefix, dir)
+    fh = self._filesystem.CreateFile(filename, st_mode=stat.S_IFREG|0o600)
+    fd = self._filesystem.AddOpenFile(fh)
+
+    self._mktemp_retvals.append(filename)
+    return (fd, filename)
+
+  # pylint: disable-msg=C6409
+  def mkdtemp(self, suffix='', prefix=None, dir=None):
+    """Create temp directory, returns string, absolute pathname.
+
+    Python 2.4.1 tempfile.mkdtemp.__doc__ =
+    >mkdtemp([suffix[, prefix[, dir]]])
+    >Creates a temporary directory in the most secure manner
+    >possible. [...]
+    >
+    >The user of mkdtemp() is responsible for deleting the temporary
+    >directory and its contents when done with it.
+    > [...]
+    >mkdtemp() returns the absolute pathname of the new directory. [...]
+
+    Args:
+      suffix: optional string, filename suffix
+      prefix: optional string, filename prefix
+      dir: optional string, directory for temp dir. Must exist before call
+    Returns:
+      string, directory name
+    """
+    dirname = self._TempEntryname(suffix, prefix, dir)
+    self._filesystem.CreateDirectory(dirname, perm_bits=0o700)
+
+    self._mktemp_retvals.append(dirname)
+    return dirname
+
+  def _TempEntryname(self, suffix, prefix, dir):
+    """Helper function for mk[ds]temp.
+
+    Args:
+      suffix: string, filename suffix
+      prefix: string, filename prefix
+      dir: string, directory for temp dir. Must exist before call
+    Returns:
+      string, entry name
+    """
+    # default dir affected by "global"
+    if dir is None:
+      call_mkdir = True
+      dir = self.gettempdir()
+    else:
+      call_mkdir = False
+
+    entryname = None
+    while not entryname or self._filesystem.Exists(entryname):
+      entryname = self._TempFilename(suffix=suffix, prefix=prefix, dir=dir)
+    if not call_mkdir:
+      # This is simplistic. A bad input of suffix=/f will cause tempfile
+      # to blow up, but this mock won't.  But that's already a broken
+      # corner case
+      parent_dir = os.path.dirname(entryname)
+      try:
+        self._filesystem.GetObject(parent_dir)
+      except IOError as err:
+        assert 'No such file or directory' in str(err)
+        # python -c 'import tempfile; tempfile.mkstemp(dir="/no/such/dr")'
+        # OSError: [Errno 2] No such file or directory: '/no/such/dr/tmpFBuqjO'
+        raise OSError(
+            errno.ENOENT,
+            'No such directory in mock filesystem',
+            parent_dir)
+    return entryname
+
+  # pylint: disable-msg=C6409
+  def gettempdir(self):
+    """Get default temp dir.  Sets default if unset."""
+    if self.tempdir:
+      return self.tempdir
+    # pylint: disable-msg=C6002
+    # TODO: environment variables TMPDIR TEMP TMP, or other dirs?
+    self.tempdir = '/tmp'
+    return self.tempdir
+
+  # pylint: disable-msg=C6409
+  def gettempprefix(self):
+    """Get temp filename prefix.
+
+    NOTE: This has no effect on py2.4
+
+    Returns:
+      string, prefix to use in temporary filenames
+    """
+    return self._temp_prefix
+
+  # pylint: disable-msg=C6409
+  def mktemp(self, suffix=''):
+    """mktemp is deprecated in 2.4.1, and is thus unimplemented."""
+    raise NotImplementedError
+
+  def _SetTemplate(self, template):
+    """Setter for 'template' property."""
+    self._temp_prefix = template
+    logging.error('tempfile.template= is a NOP in python2.4')
+
+  def __SetTemplate(self, template):
+    """Indirect setter for 'template' property."""
+    self._SetTemplate(template)
+
+  def __DeprecatedTemplate(self):
+    """template property implementation."""
+    raise NotImplementedError
+
+  # reading from template is deprecated, setting is ok.
+  template = property(__DeprecatedTemplate, __SetTemplate,
+                      doc="""Set the prefix for temp filenames""")
+
+  def FakeReturnedMktempValues(self):
+    """For validation purposes, mktemp()'s return values are stored."""
+    return self._mktemp_retvals
+
+  def FakeMktempReset(self):
+    """Clear the stored mktemp() values."""
+    self._mktemp_retvals = []