Replace spam.acquire() try: ... finally: spam.release() with "with spam:"

Lib/threading.py

@@ -347,27 +347,18 @@ class _Event(_Verbose):
         return self.__flag
 
     def set(self):
-        self.__cond.acquire()
-        try:
+        with self.__cond:
             self.__flag = True
             self.__cond.notifyAll()
-        finally:
-            self.__cond.release()
 
     def clear(self):
-        self.__cond.acquire()
-        try:
+        with self.__cond:
             self.__flag = False
-        finally:
-            self.__cond.release()
 
     def wait(self, timeout=None):
-        self.__cond.acquire()
-        try:
+        with self.__cond:
             if not self.__flag:
                 self.__cond.wait(timeout)
-        finally:
-            self.__cond.release()
 
 # Helper to generate new thread names
 _counter = 0
@@ -531,10 +522,9 @@ class Thread(_Verbose):
                 pass
 
     def __stop(self):
-        self.__block.acquire()
-        self.__stopped = True
-        self.__block.notifyAll()
-        self.__block.release()
+        with self.__block:
+            self.__stopped = True
+            self.__block.notifyAll()
 
     def __delete(self):
         "Remove current thread from the dict of currently running threads."
@@ -560,15 +550,12 @@ class Thread(_Verbose):
         # since it isn't if dummy_threading is *not* being used then don't
         # hide the exception.
 
-        _active_limbo_lock.acquire()
-        try:
+        with _active_limbo_lock:
             try:
                 del _active[_get_ident()]
             except KeyError:
                 if 'dummy_threading' not in _sys.modules:
                     raise
-        finally:
-            _active_limbo_lock.release()
 
     def join(self, timeout=None):
         if not self.__initialized:
@@ -581,8 +568,7 @@ class Thread(_Verbose):
         if __debug__:
             if not self.__stopped:
                 self._note("%s.join(): waiting until thread stops", self)
-        self.__block.acquire()
-        try:
+        with self.__block:
             if timeout is None:
                 while not self.__stopped:
                     self.__block.wait()
@@ -600,8 +586,6 @@ class Thread(_Verbose):
                 else:
                     if __debug__:
                         self._note("%s.join(): thread stopped", self)
-        finally:
-            self.__block.release()
 
     def getName(self):
         assert self.__initialized, "Thread.__init__() not called"