Setup Python typechecking

.github/workflows/ci.yml

@@ -30,3 +30,4 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: astral-sh/setup-uv@v6
+      - run: uv run ty check

pyproject.toml

@@ -22,6 +22,7 @@ dev = [
   "pytest-lsp==1.0.0b2",
   "pytest>=8.4.1",
   "ruff>=0.12.1",
+  "ty>=0.0.1a18",
 ]
 
 [build-system]

src/marimo_lsp/server.py

@@ -131,7 +131,10 @@ async def serialize(args: SerializeRequest):
             header=Header(**(raw.get("header") or {})),
             version=raw.get("version", None),
             cells=[CellDef(**cell) for cell in raw["cells"]],
-            violations=[Violation(**v) for v in raw["violations"]],
+            violations=[
+                Violation(description=v.pop("description"), **v)
+                for v in raw["violations"]
+            ],
             valid=raw["valid"],
         )
         return {"source": MarimoConvert.from_ir(ir).to_py()}

src/marimo_lsp/session_manager.py

@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from typing import TYPE_CHECKING
+import typing
 from uuid import uuid4
 
 from marimo._config.manager import (
@@ -16,7 +16,8 @@
 from marimo_lsp.loggers import get_logger
 from marimo_lsp.session_consumer import LspSessionConsumer
 
-if TYPE_CHECKING:
+if typing.TYPE_CHECKING:
+    from marimo._server.file_manager import AppFileManager
     from pygls.lsp.server import LanguageServer
 
 
@@ -89,7 +90,7 @@ def create_session(self, *, server: LanguageServer, notebook_uri: str) -> Sessio
             session_consumer=LspSessionConsumer(server, notebook_uri),
             queue_manager=queue_manager,
             kernel_manager=kernel_manager,
-            app_file_manager=app_file_manager,
+            app_file_manager=typing.cast("AppFileManager", app_file_manager),
             config_manager=config_manager,
             ttl_seconds=0,  # No TTL for LSP
         )