gh-138253: Fix compatibility of sub-interpreters queues with queue.Queue (GH-138256)

Add the block parameter in the put() and get() methods of
the concurrent.interpreters queues for compatibility with the
queue.Queue interface.

Author: serhiy-storchaka

Lib/concurrent/interpreters/_queues.py

@@ -170,13 +170,13 @@ def full(self):
     def qsize(self):
         return _queues.get_count(self._id)
 
-    def put(self, obj, timeout=None, *,
+    def put(self, obj, block=True, timeout=None, *,
             unbounditems=None,
             _delay=10 / 1000,  # 10 milliseconds
             ):
         """Add the object to the queue.
 
-        This blocks while the queue is full.
+        If "block" is true, this blocks while the queue is full.
 
         For most objects, the object received through Queue.get() will
         be a new one, equivalent to the original and not sharing any
@@ -209,6 +209,8 @@ def put(self, obj, timeout=None, *,
         If "unbounditems" is UNBOUND then it is returned by get() in place
         of the unbound item.
         """
+        if not block:
+            return self.put_nowait(obj, unbounditems=unbounditems)
         if unbounditems is None:
             unboundop = -1
         else:
@@ -235,17 +237,19 @@ def put_nowait(self, obj, *, unbounditems=None):
             unboundop, = _serialize_unbound(unbounditems)
         _queues.put(self._id, obj, unboundop)
 
-    def get(self, timeout=None, *,
+    def get(self, block=True, timeout=None, *,
             _delay=10 / 1000,  # 10 milliseconds
             ):
         """Return the next object from the queue.
 
-        This blocks while the queue is empty.
+        If "block" is true, this blocks while the queue is empty.
 
         If the next item's original interpreter has been destroyed
         then the "next object" is determined by the value of the
         "unbounditems" argument to put().
         """
+        if not block:
+            return self.get_nowait()
         if timeout is not None:
             timeout = int(timeout)
             if timeout < 0:

Lib/test/test_interpreters/test_queues.py

@@ -11,7 +11,7 @@
 from concurrent.interpreters import _queues as queues, _crossinterp
 from .utils import _run_output, TestBase as _TestBase
 
-
+HUGE_TIMEOUT = 3600
 REPLACE = _crossinterp._UNBOUND_CONSTANT_TO_FLAG[_crossinterp.UNBOUND]
 
 
@@ -306,6 +306,8 @@ def test_put_timeout(self):
         queue.put(None)
         with self.assertRaises(queues.QueueFull):
             queue.put(None, timeout=0.1)
+        with self.assertRaises(queues.QueueFull):
+            queue.put(None, HUGE_TIMEOUT, 0.1)
         queue.get()
         queue.put(None)
 
@@ -315,6 +317,10 @@ def test_put_nowait(self):
         queue.put_nowait(None)
         with self.assertRaises(queues.QueueFull):
             queue.put_nowait(None)
+        with self.assertRaises(queues.QueueFull):
+            queue.put(None, False)
+        with self.assertRaises(queues.QueueFull):
+            queue.put(None, False, timeout=HUGE_TIMEOUT)
         queue.get()
         queue.put_nowait(None)
 
@@ -345,11 +351,17 @@ def test_get_timeout(self):
         queue = queues.create()
         with self.assertRaises(queues.QueueEmpty):
             queue.get(timeout=0.1)
+        with self.assertRaises(queues.QueueEmpty):
+            queue.get(HUGE_TIMEOUT, 0.1)
 
     def test_get_nowait(self):
         queue = queues.create()
         with self.assertRaises(queues.QueueEmpty):
             queue.get_nowait()
+        with self.assertRaises(queues.QueueEmpty):
+            queue.get(False)
+        with self.assertRaises(queues.QueueEmpty):
+            queue.get(False, timeout=HUGE_TIMEOUT)
 
     def test_put_get_full_fallback(self):
         expected = list(range(20))

Misc/NEWS.d/next/Library/2025-08-30-10-58-15.gh-issue-138253.9Ehj-N.rst

@@ -0,0 +1,3 @@
+Add the *block* parameter in the :meth:`!put` and :meth:`!get` methods
+of the :mod:`concurrent.interpreters` queues for compatibility with the
+:class:`queue.Queue` interface.