Add type hints to axelrod_second, backstabber, defector

axelrod/strategies/axelrod_second.py

@@ -5,6 +5,7 @@
 import random
 
 from axelrod import Actions, Player, flip_action, random_choice
+from axelrod.actions import Action
 
 C, D = Actions.C, Actions.D
 
@@ -35,7 +36,7 @@ class Champion(Player):
         'manipulates_state': False
     }
 
-    def strategy(self, opponent):
+    def strategy(self, opponent: Player) -> Action:
         current_round = len(self.history)
         expected_length = self.match_attributes['length']
         # Cooperate for the first 1/20-th of the game
@@ -81,7 +82,7 @@ class Eatherley(Player):
     }
 
     @staticmethod
-    def strategy(opponent):
+    def strategy(opponent: Player) -> Action:
         # Cooperate on the first move
         if not len(opponent.history):
             return C
@@ -118,11 +119,11 @@ class Tester(Player):
         'manipulates_state': False
     }
 
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__()
         self.is_TFT = False
 
-    def strategy(self, opponent):
+    def strategy(self, opponent: Player) -> Action:
         # Defect on the first move
         if not opponent.history:
             return D

axelrod/strategies/backstabber.py

@@ -1,5 +1,6 @@
 from axelrod import Actions, Player
 from axelrod.strategy_transformers import FinalTransformer
+from axelrod.actions import Action
 
 C, D = Actions.C, Actions.D
 
@@ -23,7 +24,7 @@ class BackStabber(Player):
     }
 
     @staticmethod
-    def strategy(opponent):
+    def strategy(opponent: Player) -> Action:
         if not opponent.history:
             return C
         if opponent.defections > 3:
@@ -51,7 +52,7 @@ class DoubleCrosser(Player):
         'manipulates_state': False
     }
 
-    def strategy(self, opponent):
+    def strategy(self, opponent: Player) -> Action:
         cutoff = 6
 
         if not opponent.history:

axelrod/strategies/defector.py

@@ -1,4 +1,5 @@
 from axelrod import Actions, Player
+from axelrod.actions import Action
 
 C, D = Actions.C, Actions.D
 
@@ -18,7 +19,7 @@ class Defector(Player):
     }
 
     @staticmethod
-    def strategy(opponent):
+    def strategy(opponent: Player) -> Action:
         return D
 
 
@@ -36,7 +37,7 @@ class TrickyDefector(Player):
         'manipulates_state': False
     }
 
-    def strategy(self, opponent):
+    def strategy(self, opponent: Player) -> Action:
         """Almost always defects, but will try to trick the opponent into
         cooperating.
 

type_tests.sh

@@ -16,3 +16,6 @@ mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/better_an
 mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/darwin.py
 mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/cycler.py
 mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/cooperator.py
+mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/axelrod_second.py
+mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/backstabber.py
+mypy --ignore-missing-imports --follow-imports skip axelrod/strategies/defector.py