Support test with redis unstable docker (#1850)

tests/conftest.py

@@ -15,6 +15,7 @@
 REDIS_INFO = {}
 default_redis_url = "redis://localhost:6379/9"
 default_redismod_url = "redis://localhost:36379"
+default_redis_unstable_url = "redis://localhost:6378"
 
 # default ssl client ignores verification for the purpose of testing
 default_redis_ssl_url = "rediss://localhost:6666"
@@ -54,6 +55,14 @@ def pytest_addoption(parser):
         " defaults to `%(default)s`",
     )
 
+    parser.addoption(
+        "--redis-unstable-url",
+        default=default_redis_unstable_url,
+        action="store",
+        help="Redis unstable (latest version) connection string "
+        "defaults to %(default)s`",
+    )
+
 
 def _get_info(redis_url):
     client = redis.Redis.from_url(redis_url)
@@ -357,6 +366,13 @@ def master_host(request):
     yield parts.hostname, parts.port
 
 
+@pytest.fixture()
+def unstable_r(request):
+    url = request.config.getoption("--redis-unstable-url")
+    with _get_client(redis.Redis, request, from_url=url) as client:
+        yield client
+
+
 def wait_for_command(client, monitor, command, key=None):
     # issue a command with a key name that's local to this process.
     # if we find a command with our key before the command we're waiting