Extend mypy checks to test/

.github/workflows/ccpp.yml

@@ -129,24 +129,15 @@
 
       - name: Build Python interface
         run: |
-          pip install --check-build-dependencies --no-build-isolation --config-settings=cmake.build-type="Developer" 'python/[test]'
+          pip install --check-build-dependencies --no-build-isolation --config-settings=cmake.build-type="Developer" 'python/[test,mypy]'
           python -c "from mpi4py import MPI; import dolfinx; assert not dolfinx.has_petsc; assert not dolfinx.has_petsc4py; assert dolfinx.has_superlu_dist"
 
       - name: Run mypy
-        working-directory: python
-        run: |
-          pip install mypy types-cffi scipy-stubs
-          mypy -p dolfinx
-
-      - name: Run mypy  # Use a venv to avoid NumPy upgrades that are incompatible with numba
-        working-directory: python
         run: |
-          python -m venv mypy-env
-          . ./mypy-env/bin/activate
-          pip install mypy types-cffi scipy-stubs
-          mypy -p dolfinx
+          mypy --config-file python/pyproject.toml -p dolfinx # package mode, type checks installed dolfinx (working around name collision in python/ directory)
+          cd python/
           mypy test
-          mypy demo
+          #mypy demo # TODO: Enable this in future
 
       - name: Install gmsh and pyvista (and dependencies)
         run: |

python/README.md

@@ -6,15 +6,29 @@ Below is guidance for building the DOLFINx Python interface.
 
 2. Ensure the Python interface build requirements are installed:
 
-          pip install scikit-build-core
-          python -m scikit_build_core.build requires | python -c "import sys, json; print(' '.join(json.load(sys.stdin)))" | xargs pip install
+       pip install scikit-build-core
+       python -m scikit_build_core.build requires | python -c "import sys, json; print(' '.join(json.load(sys.stdin)))" | xargs pip install
 
 3. Build DOLFINx Python interface:
 
-          pip install --check-build-dependencies --no-build-isolation .
+       pip install --check-build-dependencies --no-build-isolation .
 
 To build in Developer and editable mode for development:
 
      pip -v install --check-build-dependencies --config-settings=build-dir="build" --config-settings=cmake.build-type="Developer"  --config-settings=install.strip=false --no-build-isolation -e .
 
-Note that our Developer mode is significantly stricter than CMake's default Debug mode.
+Note that Developer mode is significantly stricter than CMake's default Debug mode.
+
+# Type checking with mypy
+
+1. Install DOLFINx Python with the `[mypy]` optional dependencies set, e.g.:
+
+       pip install .[mypy]
+
+2. Check with mypy, e.g.:
+
+       mypy --config-file pyproject.toml -p dolfinx
+
+   The `--config-file pyproject.toml` is mandatory to run mypy with the correct options.
+   The `-p` flag checks the built/installed package `dolfinx`, containing the C++
+   bindings and Python interface.

python/demo/demo_pyamg.py

@@ -63,7 +63,7 @@ def poisson_problem(dtype: npt.DTypeLike, solver_type: str) -> None:
         solver_type: pyamg solver type, either "ruge_stuben" or
             "smoothed_aggregation"
     """
-    real_type = np.real(dtype(0)).dtype  # type: ignore
+    real_type = np.real(np.zeros(0, dtype=dtype)).dtype
     mesh = create_box(
         comm=MPI.COMM_WORLD,
         points=[(0.0, 0.0, 0.0), (3.0, 2.0, 1.0)],
@@ -84,7 +84,7 @@ def poisson_problem(dtype: npt.DTypeLike, solver_type: str) -> None:
 
     dofs = locate_dofs_topological(V=V, entity_dim=fdim, entities=facets)
 
-    bc = dirichletbc(value=dtype(0), dofs=dofs, V=V)  # type: ignore
+    bc = dirichletbc(value=dtype(0.0), dofs=dofs, V=V)  # type: ignore
 
     u, v = ufl.TrialFunction(V), ufl.TestFunction(V)
     x = ufl.SpatialCoordinate(mesh)

python/pyproject.toml

@@ -50,6 +50,7 @@ docs = [
       "fenics-dolfinx[demo]",
 ]
 lint = ["ruff"]
+mypy = ["mypy", "types-cffi", "types-setuptools", "scipy-stubs"]
 optional = ["numba"]
 petsc4py = ["petsc4py"]
 test = [
@@ -61,12 +62,11 @@ test = [
       "fenics-dolfinx[optional]",
 ]
 ci = [
-      "mypy",
       "pytest-xdist",
-      "types-setuptools",
       "fenics-dolfinx[build]",
       "fenics-dolfinx[docs]",
       "fenics-dolfinx[lint]",
+      "fenics-dolfinx[mypy]",
       "fenics-dolfinx[optional]",
       "fenics-dolfinx[test]",
 ]
@@ -98,7 +98,6 @@ warn_unused_ignores = false
 show_error_codes = true
 ignore_missing_imports = true
 
-
 [tool.ruff]
 line-length = 100
 indent-width = 4