bug: Verify mypy can run on CI (#1650)

.github/workflows/pytest.yaml

@@ -58,6 +58,11 @@ jobs:
         run: |
           make check-format
 
+      - name: Verify code can run with mypy (not Windows)
+        if: steps.install.outcome == 'success' && (success() || failure()) && matrix.os != 'windows-latest'
+        run: |
+          make ci-check-mypy-can-run
+
   pypi:
     name: "Deploy to PyPI"
     runs-on: ubuntu-latest

Makefile

@@ -225,6 +225,14 @@ ci-install-rsconnect: FORCE
 	uv pip install "rsconnect-python @ git+https://github.com/rstudio/rsconnect-python.git"
 
 
+# This is just to check if mypy can run for other users.
+# Not added to `make check` or `make check-fix` as all lint errors are supporessed (as we use pyright).
+ci-check-mypy-can-run: FORCE
+	@echo "-------- Checking types with mypy -----------"
+	uv pip install mypy
+	mypy shiny
+
+
 # ## If caching is ever used, we could run:
 # install-deps: FORCE ## install latest dependencies
 # 	pip install --editable ".[dev,test]" --upgrade --upgrade-strategy eager

pyproject.toml

@@ -144,3 +144,10 @@ ignore = ["E302", "E501", "F403", "F405", "W503", "E203", "E701", "E704"]
 [tool.isort]
 profile = "black"
 skip = ["__init__.py", "typings/", "_dev/", ".venv", "venv", ".tox", "build"]
+
+[tool.mypy]
+# The goal of our usage of mypy is to make to sure mypy can run, not that it catches any errors (we use pyright to find our errors).
+# Therefore, ignore_errors but do not ignore runtime errors while checking
+# Note: This setting can not be done via CLI and must be set within a config
+ignore_errors = true
+exclude = ["shiny/api-examples", "shiny/templates"]

shiny/render/_data_frame_utils/_selection.py

@@ -150,8 +150,8 @@ def _has_rect(self) -> bool:
 # Should only contain a single selection area
 
 # Do not include `BrowserCellSelectionAll` as it should be represented by a row, column, or region with appropriate values.
-# class BrowserCellSelectionAll(TypedDict):
-#    type: Literal["all"]
+# # class BrowserCellSelectionAll(TypedDict):
+# #    type: Literal["all"]
 
 
 class BrowserCellSelectionNone(TypedDict):