From d938427d67685efbf07f8d44e4662f9c74b40bc8 Mon Sep 17 00:00:00 2001
From: "Nathaniel J. Smith" <njs@pobox.com>
Date: Sun, 24 Dec 2017 19:46:58 -0800
Subject: [PATCH] Remove Queue.join and Queue.task_done

Deprecated in 0.2.0 (see gh-321)
---
 trio/_sync.py           | 33 ---------------------------------
 trio/tests/test_sync.py | 36 +-----------------------------------
 2 files changed, 1 insertion(+), 68 deletions(-)

diff --git a/trio/_sync.py b/trio/_sync.py
index d42f613f71..9e6fac062c 100644
--- a/trio/_sync.py
+++ b/trio/_sync.py
@@ -5,7 +5,6 @@
 
 from . import _core
 from ._util import aiter_compat
-from ._deprecate import deprecated
 
 __all__ = [
     "Event",
@@ -800,7 +799,6 @@ class _QueueStats:
     capacity = attr.ib()
     tasks_waiting_put = attr.ib()
     tasks_waiting_get = attr.ib()
-    tasks_waiting_join = attr.ib()
 
 
 # Like queue.Queue, with the notable difference that the capacity argument is
@@ -841,8 +839,6 @@ def __init__(self, capacity):
         self._put_semaphore = Semaphore(capacity, max_value=capacity)
         self._get_semaphore = Semaphore(0, max_value=capacity)
         self._data = deque()
-        self._join_lot = _core.ParkingLot()
-        self._unprocessed = 0
 
     def __repr__(self):
         return (
@@ -879,7 +875,6 @@ def empty(self):
 
     def _put_protected(self, obj):
         self._data.append(obj)
-        self._unprocessed += 1
         self._get_semaphore.release()
 
     @_core.enable_ki_protection
@@ -936,33 +931,6 @@ async def get(self):
         await self._get_semaphore.acquire()
         return self._get_protected()
 
-    @deprecated("0.2.0", issue=321, instead=None)
-    @_core.enable_ki_protection
-    def task_done(self):
-        """Decrement the count of unfinished work.
-
-        Each :class:`Queue` object keeps a count of unfinished work, which
-        starts at zero and is incremented after each successful
-        :meth:`put`. This method decrements it again. When the count reaches
-        zero, any tasks blocked in :meth:`join` are woken.
-
-        """
-        self._unprocessed -= 1
-        if self._unprocessed == 0:
-            self._join_lot.unpark_all()
-
-    @deprecated("0.2.0", issue=321, instead=None)
-    async def join(self):
-        """Block until the count of unfinished work reaches zero.
-
-        See :meth:`task_done` for details.
-
-        """
-        if self._unprocessed == 0:
-            await _core.checkpoint()
-        else:
-            await self._join_lot.park()
-
     @aiter_compat
     def __aiter__(self):
         return self
@@ -988,5 +956,4 @@ def statistics(self):
             capacity=self.capacity,
             tasks_waiting_put=self._put_semaphore.statistics().tasks_waiting,
             tasks_waiting_get=self._get_semaphore.statistics().tasks_waiting,
-            tasks_waiting_join=self._join_lot.statistics().tasks_waiting
         )
diff --git a/trio/tests/test_sync.py b/trio/tests/test_sync.py
index 024dce39ac..7523005ce2 100644
--- a/trio/tests/test_sync.py
+++ b/trio/tests/test_sync.py
@@ -410,35 +410,6 @@ async def test_Queue():
     assert q.empty()
 
 
-async def test_Queue_join(recwarn):
-    q = Queue(2)
-    with assert_checkpoints():
-        await q.join()
-
-    record = []
-
-    async def do_join(q):
-        record.append("started")
-        await q.join()
-        record.append("finished")
-
-    async with _core.open_nursery() as nursery:
-        await q.put(None)
-        nursery.start_soon(do_join, q)
-        nursery.start_soon(do_join, q)
-        await wait_all_tasks_blocked()
-        assert record == ["started", "started"]
-        q.put_nowait(None)
-        q.get_nowait()
-        q.get_nowait()
-        q.task_done()
-        await wait_all_tasks_blocked()
-        assert record == ["started", "started"]
-        q.task_done()
-
-    assert record == ["started", "started", "finished", "finished"]
-
-
 async def test_Queue_iter():
     q = Queue(1)
 
@@ -459,8 +430,7 @@ async def consumer():
         nursery.start_soon(consumer)
 
 
-# XX remove the 'recwarn' fixture after join is removed
-async def test_Queue_statistics(recwarn):
+async def test_Queue_statistics():
     q = Queue(3)
     q.put_nowait(1)
     statistics = q.statistics()
@@ -468,7 +438,6 @@ async def test_Queue_statistics(recwarn):
     assert statistics.capacity == 3
     assert statistics.tasks_waiting_put == 0
     assert statistics.tasks_waiting_get == 0
-    assert statistics.tasks_waiting_join == 0
 
     async with _core.open_nursery() as nursery:
         q.put_nowait(2)
@@ -476,14 +445,12 @@ async def test_Queue_statistics(recwarn):
         assert q.full()
         nursery.start_soon(q.put, 4)
         nursery.start_soon(q.put, 5)
-        nursery.start_soon(q.join)
         await wait_all_tasks_blocked()
         statistics = q.statistics()
         assert statistics.qsize == 3
         assert statistics.capacity == 3
         assert statistics.tasks_waiting_put == 2
         assert statistics.tasks_waiting_get == 0
-        assert statistics.tasks_waiting_join == 1
         nursery.cancel_scope.cancel()
 
     q = Queue(4)
@@ -497,7 +464,6 @@ async def test_Queue_statistics(recwarn):
         assert statistics.capacity == 4
         assert statistics.tasks_waiting_put == 0
         assert statistics.tasks_waiting_get == 3
-        assert statistics.tasks_waiting_join == 0
         nursery.cancel_scope.cancel()