Bring trio-asyncio into the next decade

.travis.yml

@@ -1,40 +1,22 @@
 language: python
-python:
-  - 3.6
-  - 3.6-dev
-sudo: false
-dist: trusty
+dist: xenial
 
 matrix:
   include:
-    # As of 2018-07-05, Travis's 3.7 and 3.8 builds only work if you
-    # use dist: xenial AND sudo: required
-    # See: https://github.com/python-trio/trio/pull/556#issuecomment-402879391
+    - python: 3.5
+    - python: 3.6
     - python: 3.7
-      dist: xenial
-      sudo: required
     - python: 3.7-dev
-      dist: xenial
-      sudo: required
+    - python: 3.8
     - python: 3.8-dev
-      dist: xenial
-      sudo: required
-    # - os: linux
-    #   language: generic
-    #   env: USE_PYPY_RELEASE_VERSION=5.9-beta
-    # Uncomment if you want to test on pypy nightly
-    # - os: linux
-    #   language: generic
-    #   env: USE_PYPY_NIGHTLY=1
+    - python: nightly
     - os: osx
       language: generic
       env: MACPYTHON=3.6.3
     - python: 3.6
       env: CHECK_DOCS=1
     - python: 3.6
       env: CHECK_FORMATTING=1
-  allow_failures:
-    - python: 3.8-dev
 
 script:
   - ci/travis.sh

README.rst

@@ -26,18 +26,18 @@
 **Trio-Asyncio** is a re-implementation of the ``asyncio`` mainloop on top of
 Trio.
 
-Trio-Asyncio requires Python 3.6 or 3.7. It should work on Python 3.5.3, but
-that's not tested, as the test suite requires 3.6.
+Trio-Asyncio requires at least Python 3.5.3. It is tested on recent versions of
+3.5, 3.6, 3.7, 3.8, and nightly.
 
 +++++++++++
  Rationale
 +++++++++++
 
 Trio has native concepts of tasks and task cancellation. Asyncio is based
 on callbacks and chaining Futures, albeit with nicer syntax, which make
-handling of failures and timeouts fundamentally less reliable, esp. in
+handling of failures and timeouts fundamentally less reliable, especially in
 larger programs. Thus, you *really* want to base your async project on Trio.
- 
+
 On the other hand, there are quite a few asyncio-enhanced libraries. You
 *really* don't want to re-invent any wheels in your project.
 

ci/travis.sh

@@ -92,7 +92,7 @@ else
     mkdir empty
     cd empty
 
-    pytest -W error -ra -v --cov=trio_asyncio --cov-config=../.coveragerc --verbose ../tests
+    pytest -ra -v --cov=trio_asyncio --cov-config=../.coveragerc --verbose ../tests
 
     bash <(curl -s https://codecov.io/bash)
 fi

newsfragments/66.feature.rst

@@ -0,0 +1,3 @@
+Substantially reorganize monkeypatching for asyncio event loop and
+event loop policy accessors, fixing support for Python 3.8. Also, stop
+using features deprecated in Trio 0.12.

setup.py

@@ -53,7 +53,7 @@
 """
 
 install_requires = [
-    "trio >= 0.11.0",
+    "trio >= 0.12.0",
     "async_generator >= 1.6",
     "outcome",
 ]

tests/__init__.py

@@ -11,29 +11,3 @@
 aRepr.maxother = 9999
 aRepr.maxlong = 9999
 del aRepr
-
-# Find the test SSL keys.
-from . import utils as test_utils
-
-
-def finish_request(self, request, client_address):
-    import os
-    import ssl
-    here = os.path.join(os.path.dirname(__file__), 'python')
-    keyfile = os.path.join(here, 'ssl_key.pem')
-    certfile = os.path.join(here, 'ssl_cert.pem')
-    context = ssl.SSLContext()
-    context.load_cert_chain(certfile, keyfile)
-
-    ssock = context.wrap_socket(request, server_side=True)
-    try:
-        self.RequestHandlerClass(ssock, client_address, self)
-        ssock.close()
-    except OSError:
-        # maybe socket has been closed by peer
-        pass
-
-
-test_utils.SSLWSGIServerMixin.finish_request = finish_request
-del test_utils
-del finish_request

tests/interop/test_adapter.py

@@ -1,4 +1,5 @@
 import pytest
+from async_generator import async_generator, yield_
 from trio_asyncio import aio_as_trio, trio_as_aio, allow_asyncio
 from trio_asyncio import aio2trio, trio2aio
 import asyncio
@@ -72,39 +73,43 @@ async def dly_asyncio(self, do_test=True):
         self.flag |= 1
         return 4
 
+    @async_generator
     async def iter_asyncio(self, do_test=True):
         if do_test and sys.version_info >= (3, 7):
             assert sniffio.current_async_library() == "asyncio"
         await asyncio.sleep(0.01, loop=self.loop)
-        yield 1
+        await yield_(1)
         await asyncio.sleep(0.01, loop=self.loop)
-        yield 2
+        await yield_(2)
         await asyncio.sleep(0.01, loop=self.loop)
         self.flag |= 1
 
+    @async_generator
     async def iter_trio(self):
         if sys.version_info >= (3, 7):
             assert sniffio.current_async_library() == "trio"
         await trio.sleep(0.01)
-        yield 1
+        await yield_(1)
         await trio.sleep(0.01)
-        yield 2
+        await yield_(2)
         await trio.sleep(0.01)
         self.flag |= 1
 
     @asynccontextmanager
+    @async_generator
     async def ctx_asyncio(self):
         await asyncio.sleep(0.01, loop=self.loop)
         self.flag |= 1
-        yield self
+        await yield_(self)
         await asyncio.sleep(0.01, loop=self.loop)
         self.flag |= 2
 
     @asynccontextmanager
+    @async_generator
     async def ctx_trio(self):
         await trio.sleep(0.01)
         self.flag |= 1
-        yield self
+        await yield_(self)
         await trio.sleep(0.01)
         self.flag |= 2
 

tests/interop/test_calls.py

@@ -2,6 +2,7 @@
 import asyncio
 import trio
 import sniffio
+from async_generator import async_generator, yield_
 from trio_asyncio import aio_as_trio, trio_as_aio
 from tests import aiotest
 from functools import partial
@@ -302,7 +303,7 @@ async def test_asyncio_trio_cancel_out(self, loop):
         async def cancelled_trio(seen):
             seen.flag |= 1
             await trio.sleep(0.01)
-            scope = trio.hazmat.current_task()._cancel_stack[-1]
+            scope = trio.hazmat.current_task()._cancel_status._scope
             scope.cancel()
             seen.flag |= 2
             await trio.sleep(0.01)
@@ -525,21 +526,23 @@ def err_asyncio():
 
     @pytest.mark.trio
     async def test_trio_asyncio_generator(self, loop):
+        @async_generator
         async def dly_asyncio():
-            yield 1
+            await yield_(1)
             await asyncio.sleep(0.01, loop=loop)
-            yield 2
+            await yield_(2)
 
         with test_utils.deprecate(self):
             res = await async_gen_to_list(loop.wrap_generator(dly_asyncio))
         assert res == [1, 2]
 
     @pytest.mark.trio
     async def test_trio_asyncio_generator_with_error(self, loop):
+        @async_generator
         async def dly_asyncio():
-            yield 1
+            await yield_(1)
             raise RuntimeError("I has an owie")
-            yield 2
+            await yield_(2)
 
         with test_utils.deprecate(self):
             with pytest.raises(RuntimeError) as err:
@@ -548,8 +551,9 @@ async def dly_asyncio():
 
     @pytest.mark.trio
     async def test_trio_asyncio_generator_with_cancellation(self, loop):
+        @async_generator
         async def dly_asyncio(hold, seen):
-            yield 1
+            await yield_(1)
             seen.flag |= 1
             await hold.wait()
 
@@ -569,10 +573,11 @@ async def cancel_soon(nursery):
 
     @pytest.mark.trio
     async def test_trio_asyncio_iterator(self, loop):
+        @async_generator
         async def slow_nums():
             for n in range(1, 6):
-                asyncio.sleep(0.01, loop=loop)
-                yield n
+                await asyncio.sleep(0.01, loop=loop)
+                await yield_(n)
 
         sum = 0
         async for n in aio_as_trio(slow_nums()):
@@ -581,10 +586,11 @@ async def slow_nums():
 
     @pytest.mark.trio
     async def test_trio_asyncio_iterator_depr(self, loop):
+        @async_generator
         async def slow_nums():
             for n in range(1, 6):
-                asyncio.sleep(0.01, loop=loop)
-                yield n
+                await asyncio.sleep(0.01, loop=loop)
+                await yield_(n)
 
         sum = 0
         # with test_utils.deprecate(self): ## not yet

tests/pytest.ini

@@ -0,0 +1,6 @@
+[pytest]
+filterwarnings =
+    error
+    ignore:The loop argument is deprecated since Python 3.8:DeprecationWarning
+    ignore:"@coroutine" decorator is deprecated since Python 3.8:DeprecationWarning
+    default:Tried to add marker .* but that test doesn't exist.:RuntimeWarning

tests/python/__init__.py

@@ -1,16 +0,0 @@
-import os
-from test.support import load_package_tests, import_module
-
-# Skip tests if we don't have concurrent.futures.
-import_module('concurrent.futures')
-
-
-def load_tests(*args):
-    return load_package_tests(os.path.dirname(__file__), *args)
-
-
-# this code is from
-# git@github.com:python/cpython.git
-# Revision d48ecebad
-# Python 3.6.4
-#