Add infra_libs as a bootstrap dependency.

infra_libs/utils.py

-# Copyright 2015 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.
-
-"""Miscellaneous utility functions."""
-
-
-import contextlib
-import errno
-import json
-import os
-import shutil
-import subprocess
-import sys
-import tempfile
-import time
-
-
-def read_json_as_utf8(filename=None, text=None):
-  """Read and deserialize a json file or string.
-
-  This function is different from json.load and json.loads in that it
-  returns utf8-encoded string for keys and values instead of unicode.
-
-  Args:
-    filename (str): path of a file to parse
-    text (str): json string to parse
-
-  ``filename`` and ``text`` are mutually exclusive. ValueError is raised if
-  both are provided.
-  """
-
-  if filename is not None and text is not None:
-    raise ValueError('Only one of "filename" and "text" can be provided at '
-                     'the same time')
-
-  if filename is None and text is None:
-    raise ValueError('One of "filename" and "text" must be provided')
-
-  def to_utf8(obj):
-    if isinstance(obj, dict):
-      return {to_utf8(key): to_utf8(value) for key, value in obj.iteritems()}
-    if isinstance(obj, list):
-      return [to_utf8(item) for item in obj]
-    if isinstance(obj, unicode):
-      return obj.encode('utf-8')
-    return obj
-
-  if filename:
-    with open(filename, 'rb') as f:
-      obj = json.load(f)
-  else:
-    obj = json.loads(text)
-
-  return to_utf8(obj)
-
-
-# TODO(hinoka): Add tests crbug.com/500781
-def rmtree(file_path):  # pragma: no cover
-  """Recursively removes a directory, even if it's marked read-only.
-
-  Remove the directory located at file_path, if it exists.
-
-  shutil.rmtree() doesn't work on Windows if any of the files or directories
-  are read-only, which svn repositories and some .svn files are.  We need to
-  be able to force the files to be writable (i.e., deletable) as we traverse
-  the tree.
-
-  Even with all this, Windows still sometimes fails to delete a file, citing
-  a permission error (maybe something to do with antivirus scans or disk
-  indexing).  The best suggestion any of the user forums had was to wait a
-  bit and try again, so we do that too.  It's hand-waving, but sometimes it
-  works. :/
-  """
-  if not os.path.exists(file_path):
-    return
-
-  if sys.platform == 'win32':
-    # Give up and use cmd.exe's rd command.
-    file_path = os.path.normcase(file_path)
-    for _ in xrange(3):
-      if not subprocess.call(['cmd.exe', '/c', 'rd', '/q', '/s', file_path]):
-        break
-      time.sleep(3)
-    return
-
-  def remove_with_retry(rmfunc, path):
-    if os.path.islink(path):
-      return os.remove(path)
-    else:
-      return rmfunc(path)
-
-  def rmtree_on_error(function, _, excinfo):
-    """This works around a problem whereby python 2.x on Windows has no ability
-    to check for symbolic links.  os.path.islink always returns False.  But
-    shutil.rmtree will fail if invoked on a symbolic link whose target was
-    deleted before the link.  E.g., reproduce like this:
-    > mkdir test
-    > mkdir test\1
-    > mklink /D test\current test\1
-    > python -c "import infra_libs; infra_libs.rmtree('test')"
-    To avoid this issue, we pass this error-handling function to rmtree.  If
-    we see the exact sort of failure, we ignore it.  All other failures we re-
-    raise.
-    """
-
-    exception_type = excinfo[0]
-    exception_value = excinfo[1]
-    # If shutil.rmtree encounters a symbolic link on Windows, os.listdir will
-    # fail with a WindowsError exception with an ENOENT errno (i.e., file not
-    # found).  We'll ignore that error.  Note that WindowsError is not defined
-    # for non-Windows platforms, so we use OSError (of which it is a subclass)
-    # to avoid lint complaints about an undefined global on non-Windows
-    # platforms.
-    if (function is os.listdir) and issubclass(exception_type, OSError):
-      if exception_value.errno != errno.ENOENT:
-        raise
-    else:
-      raise
-
-  for root, dirs, files in os.walk(file_path, topdown=False):
-    # For POSIX:  making the directory writable guarantees removability.
-    # Windows will ignore the non-read-only bits in the chmod value.
-    os.chmod(root, 0770)
-    for name in files:
-      remove_with_retry(os.remove, os.path.join(root, name))
-    for name in dirs:
-      remove_with_retry(lambda p: shutil.rmtree(p, onerror=rmtree_on_error),
-                        os.path.join(root, name))
-
-  remove_with_retry(os.rmdir, file_path)
-
-
-# We're trying to be compatible with Python3 tempfile.TemporaryDirectory
-# context manager here. And they used 'dir' as a keyword argument.
-# pylint: disable=redefined-builtin
-@contextlib.contextmanager
-def temporary_directory(suffix="", prefix="tmp", dir=None,
-                        keep_directory=False):
-  """Create and return a temporary directory.  This has the same
-  behavior as mkdtemp but can be used as a context manager.  For
-  example:
-
-    with temporary_directory() as tmpdir:
-      ...
-
-  Upon exiting the context, the directory and everything contained
-  in it are removed.
-
-  Args:
-    suffix, prefix, dir: same arguments as for tempfile.mkdtemp.
-    keep_directory (bool): if True, do not delete the temporary directory
-      when exiting. Useful for debugging.
-
-  Returns:
-    tempdir (str): full path to the temporary directory.
-  """
-  tempdir = None  # Handle mkdtemp raising an exception
-  try:
-    tempdir = tempfile.mkdtemp(suffix, prefix, dir)
-    yield tempdir
-
-  finally:
-    if tempdir and not keep_directory:  # pragma: no branch
-      try:
-        # TODO(pgervais,496347) Make this work reliably on Windows.
-        shutil.rmtree(tempdir, ignore_errors=True)
-      except OSError as ex:  # pragma: no cover
-        print >> sys.stderr, (
-          "ERROR: {!r} while cleaning up {!r}".format(ex, tempdir))