mypy: add config and enforce in ci

Author: CameronBrooks11

.github/workflows/ci.yml

@@ -14,6 +14,45 @@ env:
   VCPKG_COMMIT: "66c0373dc7fca549e5803087b9487edfe3aca0a1"
 
 jobs:
+  python-typecheck:
+    name: Python Type Checking (mypy)
+    runs-on: ubuntu-24.04
+    timeout-minutes: 10
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          submodules: recursive
+
+      - name: Validate requirements lockfile
+        shell: bash
+        run: |
+          set -euo pipefail
+          LOCKFILE="requirements-lock.txt"
+          test -f "$LOCKFILE"
+          if od -An -tx1 "$LOCKFILE" | tr -s ' ' '\n' | grep -qx '00'; then
+            echo "ERROR: $LOCKFILE contains NUL bytes (binary corruption)" >&2
+            exit 1
+          fi
+          iconv -f UTF-8 -t UTF-8 "$LOCKFILE" > /dev/null 2>&1
+          echo "OK: $LOCKFILE is valid UTF-8 and contains no NUL bytes"
+
+      - name: Setup Python and dependencies
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+          cache: "pip"
+          cache-dependency-path: requirements-lock.txt
+
+      - name: Install Python dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -r requirements-lock.txt
+
+      - name: Run mypy
+        run: mypy tests
+
   linux-release:
     name: ${{ matrix.lane }}
     runs-on: ubuntu-24.04

examples/inert_mode/test_inert.py

@@ -14,6 +14,7 @@
 import sys
 import time
 from pathlib import Path
+from typing import Any, cast
 
 # Add protocol_pb2 to path
 build_dir = Path(__file__).parent.parent.parent / "build"
@@ -24,12 +25,18 @@
 sys.path.insert(0, str(build_dir))
 
 try:
-    from protocol_pb2 import Request, Response, Value, ValueType
+    import protocol_pb2 as _protocol
 except ImportError:
     print("ERROR: protocol_pb2.py not found in build directory")
     print("Solution: Rebuild with: .\\scripts\\build.ps1 -Release")
     sys.exit(1)
 
+protocol = cast(Any, _protocol)
+Request = protocol.Request
+Response = protocol.Response
+Value = protocol.Value
+ValueType = protocol.ValueType
+
 
 def run_inert_example():
     # Find provider executable
@@ -180,7 +187,8 @@ def run_inert_example():
         traceback.print_exc()
         return False
     finally:
-        provider.stdin.close()
+        if provider.stdin is not None:
+            provider.stdin.close()
         provider.terminate()
         provider.wait(timeout=2)
 

examples/non_interacting_mode/test_non_interacting.py

@@ -14,6 +14,7 @@
 import sys
 import time
 from pathlib import Path
+from typing import Any, cast
 
 # Add protocol_pb2 to path
 build_dir = Path(__file__).parent.parent.parent / "build"
@@ -24,12 +25,18 @@
 sys.path.insert(0, str(build_dir))
 
 try:
-    from protocol_pb2 import Request, Response, Value, ValueType
+    import protocol_pb2 as _protocol
 except ImportError:
     print("ERROR: protocol_pb2.py not found in build directory")
     print("Solution: Rebuild with: .\\scripts\\build.ps1 -Release")
     sys.exit(1)
 
+protocol = cast(Any, _protocol)
+Request = protocol.Request
+Response = protocol.Response
+Value = protocol.Value
+ValueType = protocol.ValueType
+
 
 def run_non_interacting_example():
     # Find provider executable
@@ -194,7 +201,8 @@ def run_non_interacting_example():
         traceback.print_exc()
         return False
     finally:
-        provider.stdin.close()
+        if provider.stdin is not None:
+            provider.stdin.close()
         provider.terminate()
         provider.wait(timeout=2)
 

examples/sim_mode/test_sim.py

@@ -15,6 +15,7 @@
 import sys
 import time
 from pathlib import Path
+from typing import Any, cast
 
 # Add protocol_pb2 to path
 build_dir = Path(__file__).parent.parent.parent / "build"
@@ -25,12 +26,18 @@
 sys.path.insert(0, str(build_dir))
 
 try:
-    from protocol_pb2 import Request, Response, Value, ValueType
+    import protocol_pb2 as _protocol
 except ImportError:
     print("ERROR: protocol_pb2.py not found in build directory")
     print("Solution: Rebuild with: .\\scripts\\build.ps1 -Release")
     sys.exit(1)
 
+protocol = cast(Any, _protocol)
+Request = protocol.Request
+Response = protocol.Response
+Value = protocol.Value
+ValueType = protocol.ValueType
+
 
 def find_fluxgraph_server():
     """Find FluxGraph server executable"""
@@ -110,7 +117,10 @@ def run_sim_example():
 
         # Check if provider is still running
         if provider.poll() is not None:
-            stderr_output = provider.stderr.read().decode()
+            stderr_pipe = provider.stderr
+            stderr_output = (
+                stderr_pipe.read().decode() if stderr_pipe is not None else ""
+            )
             print("[FAIL] Provider terminated unexpectedly:")
             print(stderr_output)
             return False
@@ -198,7 +208,8 @@ def run_sim_example():
     finally:
         # Cleanup
         try:
-            provider.stdin.close()
+            if provider.stdin is not None:
+                provider.stdin.close()
             provider.terminate()
             provider.wait(timeout=2)
         except Exception:

mypy.ini

@@ -0,0 +1,12 @@
+[mypy]
+python_version = 3.12
+files = tests
+warn_unused_configs = True
+check_untyped_defs = True
+no_implicit_optional = True
+warn_redundant_casts = True
+warn_unused_ignores = True
+warn_return_any = True
+warn_unreachable = True
+strict_equality = True
+ignore_missing_imports = True

tests/support/proto_bootstrap.py

@@ -23,7 +23,7 @@ def load_protocol_module() -> tuple[ModuleType, Path]:
     add_build_dir_to_sys_path(build_dir)
 
     try:
-        import protocol_pb2 as protocol  # type: ignore
+        import protocol_pb2 as protocol
     except ImportError as exc:
         raise RuntimeError(
             f"protocol_pb2 module not found in {build_dir}.\n{_import_hint()}"