chore: add type annotations and type checking

.github/workflows/pr.yml

@@ -27,6 +27,9 @@ jobs:
     - name: Check formatting
       run: pipenv run black --target-version=py310 .
 
+    - name: Check types
+      run: pipenv run mypy rps rps-sim.py
+
     - name: Run tests
       run: |
         pipenv run pytest

Pipfile

@@ -19,6 +19,7 @@ black = "*"
 pytest = "*"
 pytest-mock = "*"
 mypy-extensions = "*"
+mypy = "*"
 
 [requires]
 python_version = "3.10"

pyproject.toml

@@ -0,0 +1,2 @@
+[tool.mypy]
+strict = true

rps/game.py

@@ -1,11 +1,14 @@
-def play_game(firstPlayer, secondPlayer):
+from .player import Player
+from .play import PlayResult
+
+def play_game(firstPlayer: Player, secondPlayer: Player) -> PlayResult:
     firstPlay = firstPlayer.play()
     secondPlay = secondPlayer.play()
     return firstPlay.match(secondPlay)
 
 
-def play_games(firstPlayer, secondPlayer, times):
+def play_games(firstPlayer: Player, secondPlayer: Player, times: int) -> list[PlayResult]:
     results = []
-    for game in range(times):
+    for _ in range(times):
         results.append(play_game(firstPlayer, secondPlayer))
     return results

rps/play.py

@@ -1,3 +1,4 @@
+from __future__ import annotations
 from enum import IntEnum
 
 
@@ -7,7 +8,7 @@ class PlayResult(IntEnum):
     WIN = 1
 
 
-def human_readable(result):
+def human_readable(result: PlayResult) -> str:
     if result == PlayResult.WIN:
         return "wins"
     elif result == PlayResult.LOSS:
@@ -21,7 +22,7 @@ class Play(IntEnum):
     PAPER = 2
     SCISSORS = 3
 
-    def match(self, other):
+    def match(self, other: Play) -> PlayResult:
         if self.value == other.value or type(other) is not Play:
             return PlayResult.DRAW
         if self.value == self.ROCK:
@@ -30,11 +31,12 @@ def match(self, other):
             return PlayResult.WIN if other.value == self.PAPER else PlayResult.LOSS
         elif self.value == self.PAPER:
             return PlayResult.WIN if other.value == self.ROCK else PlayResult.LOSS
+        return PlayResult.DRAW
 
     @staticmethod
-    def min():
+    def min() -> int:
         return min([Play.ROCK, Play.PAPER, Play.SCISSORS])
 
     @staticmethod
-    def max():
+    def max() -> int:
         return max([Play.ROCK, Play.PAPER, Play.SCISSORS])

rps/player.py

@@ -1,16 +1,18 @@
 import abc
+
+from .play import Play
 from .strategy import PlaySelectionStrategy
 
 
 class Player(object):
     @abc.abstractmethod
-    def play(self):
+    def play(self) -> Play:
         """Required method"""
 
 
 class BotPlayer(Player):
-    def __init__(self, play_strategy):
+    def __init__(self, play_strategy: PlaySelectionStrategy):
         self.__strategy = play_strategy
 
-    def play(self):
+    def play(self)  -> Play:
         return self.__strategy.play()

rps/strategy.py

@@ -7,10 +7,10 @@ class PlaySelectionStrategy(object):
     __metaclass__ = abc.ABCMeta
 
     @abc.abstractmethod
-    def play(self):
+    def play(self) -> Play:
         """Required method"""
 
 
 class RandomPlayStrategy(PlaySelectionStrategy):
-    def play(self):
+    def play(self) -> Play:
         return Play(randrange(Play.min(), Play.max() + 1))