Type hints improvements - fixing static code analyses issues related to combined sync and async return types(vectorsets + commands in core.py) (#3991)

* Type hints refactoring analyses

* POC

* Applying review comments. Updating the type hints pattern - adopting more modern syntax. VectorSets commands are fully covered

* Updating command changes analyses and progress status

* Fixing get/set args type hints to follow PEP 604

* Add agent instruction

* Updating analyses with more accurate data. Adding overloads for three batches

* Adding batch 4

* Adding batch 5

* Applying review comments

* Adding batch 6

* Adding batch 7

* Fixing linters + LSP violation

* Adding batch 8

* Adding batch 9

* Adding batch 10

* Adding batch 11 and 12 - final ones for core.py

* Fixing misplaced overloads

Author: petyaslavova

.agent/sync_async_type_hints_overload_guide.md

@@ -13,6 +13,7 @@
     Dict,
     Iterable,
     List,
+    Literal,
     Mapping,
     MutableMapping,
     Optional,
@@ -129,6 +130,9 @@ class Redis(
     Connection object to talk to redis.
     """
 
+    # Type discrimination marker for @overload self-type pattern
+    _is_async_client: Literal[True] = True
+
     response_callbacks: MutableMapping[Union[str, bytes], ResponseCallbackT]
 
     @classmethod

redis/asyncio/client.py

@@ -16,6 +16,7 @@
     Dict,
     Generator,
     List,
+    Literal,
     Mapping,
     Optional,
     Set,
@@ -238,6 +239,9 @@ def from_url(cls, url: str, **kwargs: Any) -> "RedisCluster":
             kwargs["ssl"] = True
         return cls(**kwargs)
 
+    # Type discrimination marker for @overload self-type pattern
+    _is_async_client: Literal[True] = True
+
     __slots__ = (
         "_initialize",
         "_lock",
@@ -1976,7 +1980,14 @@ class ClusterPipeline(AbstractRedis, AbstractRedisCluster, AsyncRedisClusterComm
         | Existing :class:`~.RedisCluster` client
     """
 
-    __slots__ = ("cluster_client", "_transaction", "_execution_strategy")
+    __slots__ = (
+        "cluster_client",
+        "_transaction",
+        "_execution_strategy",
+    )
+
+    # Type discrimination marker for @overload self-type pattern
+    _is_async_client: Literal[True] = True
 
     def __init__(
         self, client: RedisCluster, transaction: Optional[bool] = None

redis/asyncio/cluster.py

@@ -1,6 +1,6 @@
 import asyncio
 import logging
-from typing import Any, Awaitable, Callable, List, Optional, Union
+from typing import Any, Awaitable, Callable, List, Literal, Optional, Union
 
 from redis.asyncio.client import PubSubHandler
 from redis.asyncio.multidb.command_executor import DefaultCommandExecutor
@@ -441,6 +441,8 @@ class Pipeline(AsyncRedisModuleCommands, AsyncCoreCommands):
     Pipeline implementation for multiple logical Redis databases.
     """
 
+    _is_async_client: Literal[True] = True
+
     def __init__(self, client: MultiDBClient):
         self._command_stack = []
         self._client = client

redis/asyncio/multidb/client.py

@@ -10,6 +10,7 @@
     Callable,
     Dict,
     List,
+    Literal,
     Mapping,
     Optional,
     Set,
@@ -151,6 +152,9 @@ class Redis(RedisModuleCommands, CoreCommands, SentinelCommands):
     It is not safe to pass PubSub or Pipeline objects between threads.
     """
 
+    # Type discrimination marker for @overload self-type pattern
+    _is_async_client: Literal[False] = False
+
     @classmethod
     def from_url(cls, url: str, **kwargs) -> "Redis":
         """

redis/client.py

@@ -554,6 +554,9 @@ def replace_default_node(self, target_node: "ClusterNode" = None) -> None:
 class RedisCluster(
     AbstractRedisCluster, MaintNotificationsAbstractRedisCluster, RedisClusterCommands
 ):
+    # Type discrimination marker for @overload self-type pattern
+    _is_async_client: Literal[False] = False
+
     @classmethod
     def from_url(cls, url: str, **kwargs: Any) -> "RedisCluster":
         """