ci(typing): make mypy happy-ish

litestar/app.py

@@ -46,6 +46,7 @@
 from litestar.routes import ASGIRoute, HTTPRoute, WebSocketRoute
 from litestar.static_files.base import StaticFiles
 from litestar.stores.registry import StoreRegistry
+from litestar.template import TemplateEngineProtocol
 from litestar.types import Empty, TypeDecodersSequence
 from litestar.types.internal_types import PathParameterDefinition
 from litestar.utils import deprecated, ensure_async_callable, join_paths, unique
@@ -216,7 +217,7 @@ def __init__(
         static_files_config: Sequence[StaticFilesConfig] | None = None,
         stores: StoreRegistry | dict[str, Store] | None = None,
         tags: Sequence[str] | None = None,
-        template_config: TemplateConfig | None = None,
+        template_config: TemplateConfig[TemplateEngineProtocol] | None = None,
         type_encoders: TypeEncodersMap | None = None,
         type_decoders: TypeDecodersSequence | None = None,
         websocket_class: type[WebSocket] | None = None,

litestar/config/app.py

@@ -8,6 +8,7 @@
 from litestar.config.response_cache import ResponseCacheConfig
 from litestar.datastructures import State
 from litestar.events.emitter import SimpleEventEmitter
+from litestar.template import TemplateEngineProtocol
 from litestar.types.empty import Empty
 
 if TYPE_CHECKING:
@@ -196,7 +197,7 @@ class AppConfig:
     """
     tags: list[str] = field(default_factory=list)
     """A list of string tags that will be appended to the schema of all route handlers under the application."""
-    template_config: TemplateConfig | None = field(default=None)
+    template_config: TemplateConfig[TemplateEngineProtocol] | None = field(default=None)
     """An instance of :class:`TemplateConfig <.template.TemplateConfig>`."""
     type_encoders: TypeEncodersMap | None = field(default=None)
     """A mapping of types to callables that transform them into types supported for serialization."""

litestar/response/template.py

@@ -158,14 +158,6 @@ def to_asgi_response(
         )
 
     def _render_from_string(self, template_str: str, request: Request) -> bytes:
-        """Render the template from a string.
-
-        Args:
-            template_str: A string representing the template.
-            request: A :class:`Request <.connection.Request>` instance.
-
-        Returns:
-            Rendered content as bytes.
-        """
+        """Render the template from a string."""
         context = self.create_template_context(request)
-        return request.app.template_engine.render_string(template_str, context).encode(self.encoding)  # type: ignore[no-any-return]
+        return request.app.template_engine.render_string(template_str, context).encode(self.encoding)

tests/unit/test_template/test_template.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import sys
 from pathlib import Path
 from typing import TYPE_CHECKING, Optional, Type, Union
@@ -32,8 +34,9 @@ def invalid_path() -> Template:
 def test_engine_passed_to_callback(tmp_path: "Path") -> None:
     received_engine: Optional[JinjaTemplateEngine] = None
 
-    def callback(engine: JinjaTemplateEngine) -> None:
+    def callback(engine: TemplateEngineProtocol) -> None:
         nonlocal received_engine
+        assert isinstance(engine, JinjaTemplateEngine), "Engine must be a JinjaTemplateEngine"
         received_engine = engine
 
     app = Litestar(