Fix buffer is closed error when using PythonParser class (#1213)

* Fix buffer is closed error when using PythonParser class

Fixes #1212
Fixes #1114 

* Fix test_invalid_response on older python versions without AsyncMock

Author: Maksim Novikov

CHANGES/1212.bugfix

@@ -0,0 +1 @@
+Fix buffer is closed error when using PythonParser class

CONTRIBUTORS.txt

@@ -39,6 +39,7 @@ Jeff Moser
 Joongi Kim <achimnol>
 Kyrylo Dehtyarenko
 Leonid Shvechikov
+Maksim Novikov
 Manuel Miranda
 Marek Szapiel
 Marijn Giesen

aioredis/connection.py

@@ -373,7 +373,7 @@ def __init__(self, socket_read_size: int):
     def on_connect(self, connection: "Connection"):
         """Called when the stream connects"""
         self._stream = connection._reader
-        if self._buffer is None or self._stream is None:
+        if self._stream is None:
             raise RedisError("Buffer is closed.")
 
         self._buffer = SocketBuffer(

tests/conftest.py

@@ -8,7 +8,12 @@
 
 import aioredis
 from aioredis.client import Monitor
-from aioredis.connection import parse_url
+from aioredis.connection import (
+    HIREDIS_AVAILABLE,
+    HiredisParser,
+    PythonParser,
+    parse_url,
+)
 
 from .compat import mock
 
@@ -125,16 +130,40 @@ def skip_unless_arch_bits(arch_bits):
     )
 
 
-@pytest.fixture(params=[True, False], ids=["single", "pool"])
+@pytest.fixture(
+    params=[
+        (True, PythonParser),
+        (False, PythonParser),
+        pytest.param(
+            (True, HiredisParser),
+            marks=pytest.mark.skipif(
+                not HIREDIS_AVAILABLE, reason="hiredis is not installed"
+            ),
+        ),
+        pytest.param(
+            (False, HiredisParser),
+            marks=pytest.mark.skipif(
+                not HIREDIS_AVAILABLE, reason="hiredis is not installed"
+            ),
+        ),
+    ],
+    ids=[
+        "single-python-parser",
+        "pool-python-parser",
+        "single-hiredis",
+        "pool-hiredis",
+    ],
+)
 def create_redis(request, event_loop):
     """Wrapper around aioredis.create_redis."""
-    single_connection = request.param
+    single_connection, parser_cls = request.param
 
     async def f(url: str = request.config.getoption("--redis-url"), **kwargs):
         single = kwargs.pop("single_connection_client", False) or single_connection
+        parser_class = kwargs.pop("parser_class", None) or parser_cls
         url_options = parse_url(url)
         url_options.update(kwargs)
-        pool = aioredis.ConnectionPool(**url_options)
+        pool = aioredis.ConnectionPool(parser_class=parser_class, **url_options)
         client: aioredis.Redis = aioredis.Redis(connection_pool=pool)
         if single:
             client = client.client()

tests/test_connection.py

@@ -1,23 +1,24 @@
 import asyncio
 from typing import TYPE_CHECKING
-from unittest import mock
 
 import pytest
 
-from aioredis.connection import UnixDomainSocketConnection
+from aioredis.connection import PythonParser, UnixDomainSocketConnection
 from aioredis.exceptions import InvalidResponse
-from aioredis.utils import HIREDIS_AVAILABLE
 
-if TYPE_CHECKING:
-    from aioredis.connection import PythonParser
+from .compat import mock
 
 
-@pytest.mark.skipif(HIREDIS_AVAILABLE, reason="PythonParser only")
 @pytest.mark.asyncio
-async def test_invalid_response(r):
+@pytest.mark.parametrize("create_redis", [(True, PythonParser)], indirect=True)
+async def test_invalid_response(create_redis):
+    r = await create_redis()
+
     raw = b"x"
+    readline_mock = mock.AsyncMock(return_value=raw)
+
     parser: "PythonParser" = r.connection._parser
-    with mock.patch.object(parser._buffer, "readline", return_value=raw):
+    with mock.patch.object(parser._buffer, "readline", readline_mock):
         with pytest.raises(InvalidResponse) as cm:
             await parser.read_response()
     assert str(cm.value) == "Protocol Error: %r" % raw