bpo-30030: Revert f50354ad (tempfile) (#1187)
Revert f50354adaaafebe95ad09d09b825804a686ea843: it introduced a
regression in test_threadedtempfile.
diff --git a/Lib/tempfile.py b/Lib/tempfile.py
index 6112208..6146235 100644
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -133,21 +133,32 @@
return prefix, suffix, dir, output_type
-def _RandomNameSequence():
- """Generate an endless sequence of unpredictable strings which
- can safely be incorporated into file names. Each string is 8
- characters long. Multiple threads and forked processes can
- safely use the same instance at the same time."""
+class _RandomNameSequence:
+ """An instance of _RandomNameSequence generates an endless
+ sequence of unpredictable strings which can safely be incorporated
+ into file names. Each string is six characters long. Multiple
+ threads can safely use the same instance at the same time.
+
+ _RandomNameSequence is an iterator."""
characters = "abcdefghijklmnopqrstuvwxyz0123456789_"
- rng_pid = None
- while True:
+
+ @property
+ def rng(self):
cur_pid = _os.getpid()
- if cur_pid != rng_pid:
- choose = _Random().choice
- rng_pid = cur_pid
- letters = [choose(characters) for dummy in range(8)]
- yield ''.join(letters)
+ if cur_pid != getattr(self, '_rng_pid', None):
+ self._rng = _Random()
+ self._rng_pid = cur_pid
+ return self._rng
+
+ def __iter__(self):
+ return self
+
+ def __next__(self):
+ c = self.characters
+ choose = self.rng.choice
+ letters = [choose(c) for dummy in range(8)]
+ return ''.join(letters)
def _candidate_tempdir_list():
"""Generate a list of candidate temporary directories which
diff --git a/Lib/test/test_tempfile.py b/Lib/test/test_tempfile.py
index 367e48d..51df1ec 100644
--- a/Lib/test/test_tempfile.py
+++ b/Lib/test/test_tempfile.py
@@ -1,5 +1,4 @@
# tempfile.py unit tests.
-import collections.abc
import tempfile
import errno
import io
@@ -291,9 +290,9 @@
"""Test the internal function _get_candidate_names."""
def test_retval(self):
- # _get_candidate_names returns an iterator
+ # _get_candidate_names returns a _RandomNameSequence object
obj = tempfile._get_candidate_names()
- self.assertIsInstance(obj, collections.abc.Iterator)
+ self.assertIsInstance(obj, tempfile._RandomNameSequence)
def test_same_thing(self):
# _get_candidate_names always returns the same object