bpo-35283: Add pending deprecation warning for Thread.isAlive (GH-11604)

Add a pending deprecated warning for the threading.Thread.isAlive() method.

Author: corona10

Lib/test/support/__init__.py

@@ -2224,14 +2224,14 @@ def start_threads(threads, unlock=None):
  endtime += 60
  for t in started:
  t.join(max(endtime - time.monotonic(), 0.01))
- started = [t for t in started if t.isAlive()]
+ started = [t for t in started if t.is_alive()]
  if not started:
  break
  if verbose:
  print('Unable to join %d threads during a period of '
  '%d minutes' % (len(started), timeout))
  finally:
- started = [t for t in started if t.isAlive()]
+ started = [t for t in started if t.is_alive()]
  if started:
  faulthandler.dump_traceback(sys.stdout)
  raise AssertionError('Unable to join %d threads' % len(started))

Lib/test/test_threading.py

@@ -415,7 +415,8 @@ def test_old_threading_api(self):
  t.setDaemon(True)
  t.getName()
  t.setName("name")
- t.isAlive()
+ with self.assertWarnsRegex(PendingDeprecationWarning, 'use is_alive()'):
+ t.isAlive()
  e = threading.Event()
  e.isSet()
  threading.activeCount()

Lib/threading.py

@@ -1007,7 +1007,7 @@ def join(self, timeout=None):
  When the timeout argument is present and not None, it should be a
  floating point number specifying a timeout for the operation in seconds
  (or fractions thereof). As join() always returns None, you must call
- isAlive() after join() to decide whether a timeout happened -- if the
+ is_alive() after join() to decide whether a timeout happened -- if the
  thread is still alive, the join() call timed out.
 
  When the timeout argument is not present or None, the operation will
@@ -1091,7 +1091,15 @@ def is_alive(self):
  self._wait_for_tstate_lock(False)
  return not self._is_stopped
 
- isAlive = is_alive
+ def isAlive(self):
+ """Return whether the thread is alive.
+
+ This method is deprecated, use is_alive() instead.
+ """
+ import warnings
+ warnings.warn('isAlive() is deprecated, use is_alive() instead',
+ PendingDeprecationWarning, stacklevel=2)
+ return self.is_alive()
 
  @property
  def daemon(self):

Misc/NEWS.d/next/Library/2019-01-07-17-17-16.bpo-35283.WClosC.rst

@@ -0,0 +1,2 @@
+Add a pending deprecated warning for the :meth:`threading.Thread.isAlive` method.
+Patch by Dong-hee Na.