Add mypy to the pre-commit hooks (#421)

.pre-commit-config.yaml

@@ -25,3 +25,9 @@ repos:
           - --use-current-year
           - --no-extra-eol
           - --detect-license-in-X-top-lines=5
+  -   repo: https://github.com/pre-commit/mirrors-mypy
+      rev: 'v1.10.1'
+      hooks:
+      - id: mypy
+        exclude: "examples"
+        additional_dependencies: [types-pyyaml>=6.0]

kr8s/_exec.py

@@ -12,13 +12,13 @@
 if TYPE_CHECKING:
     from kr8s._objects import APIObject
 
-STDIN_CHANNEL = 0
-STDOUT_CHANNEL = 1
-STDERR_CHANNEL = 2
-ERROR_CHANNEL = 3
-RESIZE_CHANNEL = 4
-CLOSE_CHANNEL = 255
-EXEC_PROTOCOL = "v4.channel.k8s.io"
+STDIN_CHANNEL: int = 0
+STDOUT_CHANNEL: int = 1
+STDERR_CHANNEL: int = 2
+ERROR_CHANNEL: int = 3
+RESIZE_CHANNEL: int = 4
+CLOSE_CHANNEL: int = 255
+EXEC_PROTOCOL: str = "v4.channel.k8s.io"
 
 
 class Exec:
@@ -73,10 +73,10 @@ async def run(
                         f"{ws.protocol}, only with v5.channel.k8s.io"
                     )
                 if isinstance(self._stdin, str):
-                    await ws.send_bytes(STDIN_CHANNEL.to_bytes() + self._stdin.encode())
+                    await ws.send_bytes(STDIN_CHANNEL.to_bytes() + self._stdin.encode())  # type: ignore
                 else:
-                    await ws.send_bytes(STDIN_CHANNEL.to_bytes() + self._stdin.read())
-                await ws.send_bytes(CLOSE_CHANNEL.to_bytes() + STDIN_CHANNEL.to_bytes())
+                    await ws.send_bytes(STDIN_CHANNEL.to_bytes() + self._stdin.read())  # type: ignore
+                await ws.send_bytes(CLOSE_CHANNEL.to_bytes() + STDIN_CHANNEL.to_bytes())  # type: ignore
             while True:
                 message = await ws.receive_bytes()
                 channel, message = int(message[0]), message[1:]

pyproject.toml

@@ -128,3 +128,6 @@ dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
 
 # Assume Python 3.10.
 target-version = "py310"
+
+[tool.mypy]
+exclude = ["examples"]