Merge pull request #1052 from eric-s-s/enum_actions

Enum actions #816

axelrod/actions.py

@@ -9,31 +9,65 @@
 C, D = Actions.C, Actions.D
 """
 
-# Type alias for actions.
-Action = str
+from enum import Enum
+from typing import Iterable
+
+
+class UnknownActionError(ValueError):
+    def __init__(self, *args):
+        super(UnknownActionError, self).__init__(*args)
+
+
+class Actions(Enum):
+
+    C = 1
+    D = 0
+
+    def __bool__(self):
+        return bool(self.value)
 
+    def __repr__(self):
+        return '{}'.format(self.name)
 
-class Actions(object):
-    C = 'C'  # type: Action
-    D = 'D'  # type: Action
+    def __str__(self):
+        return '{}'.format(self.name)
+
+    def flip(self):
+        """Returns the opposite Action. """
+        if self == Actions.C:
+            return Actions.D
+        if self == Actions.D:
+            return Actions.C
+
+    @classmethod
+    def from_char(cls, character):
+        """Converts a single character into an Action. `Action.from_char('C')`
+        returns `Action.C`. `Action.from_char('CC')` raises an error. Use
+        `str_to_actions` instead."""
+        if character == 'C':
+            return cls.C
+        elif character == 'D':
+            return cls.D
+        else:
+            raise UnknownActionError('Character must be "C" or "D".')
+
+# Type alias for actions.
+Action = Actions
 
 
 def flip_action(action: Action) -> Action:
-    if action == Actions.C:
-        return Actions.D
-    elif action == Actions.D:
-        return Actions.C
-    else:
-        raise ValueError("Encountered a invalid action.")
+    if not isinstance(action, Action):
+        raise UnknownActionError('Not an Action')
+    return action.flip()
 
 
 def str_to_actions(actions: str) -> tuple:
     """Takes a string like 'CCDD' and returns a tuple of the appropriate
     actions."""
-    action_dict = {'C': Actions.C,
-                   'D': Actions.D}
-    try:
-        return tuple(action_dict[action] for action in actions)
-    except KeyError:
-        raise ValueError(
-            'The characters of "actions" str may only be "C" or "D"')
+    return tuple(Actions.from_char(element) for element in actions)
+
+
+def actions_to_str(actions: Iterable[Action]) -> str:
+    """Takes any iterable of Action and returns a string of 'C's
+    and 'D's.  ex: (D, D, C) -> 'DDC' """
+    return "".join(map(repr, actions))

axelrod/deterministic_cache.py

@@ -25,7 +25,7 @@ class DeterministicCache(UserDict):
     resulting interactions. e.g. for a 3 turn Match between Cooperator and
     Alternator, the dictionary entry would be:
 
-    (axelrod.Cooperator, axelrod.Alternator): [('C', 'C'), ('C', 'D'), ('C', 'C')]
+    (axelrod.Cooperator, axelrod.Alternator): [(C, C), (C, D), (C, C)]
 
     Most of the functionality is provided by the UserDict class (which uses an
     instance of dict as the 'data' attribute to hold the dictionary entries).

axelrod/interaction_utils.py

@@ -11,7 +11,7 @@
 import csv
 import tqdm
 
-from axelrod.actions import Actions
+from axelrod.actions import Actions, str_to_actions
 from .game import Game
 
 
@@ -255,7 +255,9 @@ def read_interactions_from_file(filename, progress_bar=True,
     with open(filename, 'r') as f:
         for row in csv.reader(f):
             index_pair = (int(row[0]), int(row[1]))
-            interaction = list(zip(row[4], row[5]))
+            p1_actions = str_to_actions(row[4])
+            p2_actions = str_to_actions(row[5])
+            interaction = list(zip(p1_actions, p2_actions))
 
             try:
                 pairs_to_interactions[index_pair].append(interaction)
@@ -275,12 +277,12 @@ def string_to_interactions(string):
     Converts a compact string representation of an interaction to an
     interaction:
 
-    'CDCDDD' -> [('C', 'D'), ('C', 'D'), ('D', 'D')]
+    'CDCDDD' -> [(C, D), (C, D), (D, D)]
     """
     interactions = []
     interactions_list = list(string)
     while interactions_list:
-        p1action = interactions_list.pop(0)
-        p2action = interactions_list.pop(0)
+        p1action = Actions.from_char(interactions_list.pop(0))
+        p2action = Actions.from_char(interactions_list.pop(0))
         interactions.append((p1action, p2action))
     return interactions

axelrod/random_.py

@@ -5,14 +5,14 @@
 
 def random_choice(p: float = 0.5) -> Action:
     """
-    Return 'C' with probability `p`, else return 'D'
+    Return C with probability `p`, else return D
 
     No random sample is carried out if p is 0 or 1.
 
     Parameters
     ----------
     p : float
-        The probability of picking 'C'
+        The probability of picking C
 
     Returns
     -------

axelrod/result_set.py

@@ -4,7 +4,7 @@
 from numpy import mean, nanmedian, std
 import tqdm
 
-from axelrod.actions import Actions
+from axelrod.actions import Actions, str_to_actions
 import axelrod.interaction_utils as iu
 from . import eigen
 from .game import Game
@@ -848,8 +848,8 @@ def summarise(self):
         for player in self.normalised_state_to_action_distribution:
             rates = []
             for state in states:
-                counts = [counter[(state, 'C')] for counter in player
-                          if counter[(state, 'C')] > 0]
+                counts = [counter[(state, C)] for counter in player
+                          if counter[(state, C)] > 0]
 
                 if len(counts) > 0:
                     rate = mean(counts)
@@ -1075,7 +1075,9 @@ def read_match_chunks(self, progress_bar=False):
             count = 0
             for row in csv_reader:
                 index_and_names = row[:4]
-                interactions = list(zip(row[4], row[5]))
+                p1_actions = str_to_actions(row[4])
+                p2_actions = str_to_actions(row[5])
+                interactions = list(zip(p1_actions, p2_actions))
                 repetitions.append(index_and_names + interactions)
                 count += 1
                 if progress_bar:

axelrod/strategies/appeaser.py

@@ -7,8 +7,8 @@
 class Appeaser(Player):
     """A player who tries to guess what the opponent wants.
 
-    Switch the classifier every time the opponent plays 'D'.
-    Start with 'C', switch between 'C' and 'D' when opponent plays 'D'.
+    Switch the classifier every time the opponent plays D.
+    Start with C, switch between C and D when opponent plays D.
 
     Names:
 

axelrod/strategies/human.py

@@ -136,7 +136,7 @@ def _get_human_input(self) -> Action:  # pragma: no cover
             get_bottom_toolbar_tokens=self.status_messages['toolbar'],
             style=toolbar_style)
 
-        return action.upper()
+        return Actions.from_char(action.upper())
 
     def strategy(self, opponent: Player, input_function=None):
         """

axelrod/strategies/lookerup.py

@@ -1,7 +1,7 @@
 from collections import namedtuple
 from itertools import product
 
-from axelrod.actions import Action, Actions, str_to_actions
+from axelrod.actions import Action, Actions, str_to_actions, actions_to_str
 from axelrod.player import Player
 
 from typing import Any, TypeVar
@@ -139,7 +139,8 @@ def display(self,
         :param sort_by: only_elements='self_plays', 'op_plays', 'op_openings'
         """
         def sorter(plays):
-            return tuple(getattr(plays, field) for field in sort_by)
+            return tuple(actions_to_str(
+                getattr(plays, field) for field in sort_by))
 
         col_width = 11
         sorted_keys = sorted(self._dict, key=sorter)
@@ -148,9 +149,12 @@ def sorter(plays):
                        '{str_list[2]:^{width}}')
         display_line = header_line.replace('|', ',') + ': {str_list[3]},'
 
-        line_elements = [(', '.join(getattr(key, sort_by[0])),
-                          ', '.join(getattr(key, sort_by[1])),
-                          ', '.join(getattr(key, sort_by[2])),
+        def make_commaed_str(action_tuple):
+            return ', '.join(str(action) for action in action_tuple)
+
+        line_elements = [(make_commaed_str(getattr(key, sort_by[0])),
+                          make_commaed_str(getattr(key, sort_by[1])),
+                          make_commaed_str(getattr(key, sort_by[2])),
                           self._dict[key])
                          for key in sorted_keys]
         header = header_line.format(str_list=sort_by, width=col_width) + '\n'

axelrod/strategies/meta.py

@@ -82,7 +82,7 @@ def strategy(self, opponent):
     def meta_strategy(self, results, opponent):
         """Determine the meta result based on results of all players.
         Override this function in child classes."""
-        return 'C'
+        return C
 
     def reset(self):
         super().reset()

axelrod/strategies/qlearner.py

@@ -1,7 +1,7 @@
 from collections import OrderedDict
 import random
 
-from axelrod.actions import Actions, Action
+from axelrod.actions import Actions, Action, actions_to_str
 from axelrod.player import Player
 from axelrod.random_ import random_choice
 
@@ -92,7 +92,9 @@ def find_state(self, opponent: Player) -> str:
         its previous proportion of playing C) as a hashable state
         """
         prob = '{:.1f}'.format(opponent.cooperations)
-        return ''.join(opponent.history[-self.memory_length:]) + prob
+        action_str = actions_to_str(
+            opponent.history[-self.memory_length:])
+        return action_str + prob
 
     def perform_q_learning(self, prev_state: str, state: str, action: Action, reward):
         """

axelrod/strategies/shortmem.py

@@ -37,8 +37,8 @@ def strategy(opponent: Player) -> Action:
             return C
 
         array = opponent.history[-10:]
-        C_counts = array.count('C')
-        D_counts = array.count('D')
+        C_counts = array.count(C)
+        D_counts = array.count(D)
 
         if C_counts - D_counts >= 3:
             return C

axelrod/strategies/stalker.py

@@ -6,7 +6,7 @@
 C, D = Actions.C, Actions.D
 
 
-@FinalTransformer((D), name_prefix=None)  # End with defection
+@FinalTransformer((D,), name_prefix=None)  # End with defection
 class Stalker(Player):
     """
 

axelrod/strategies/titfortat.py

@@ -1,4 +1,4 @@
-from axelrod.actions import Actions, Action
+from axelrod.actions import Actions, Action, actions_to_str
 from axelrod.player import Player
 from axelrod.random_ import random_choice
 from axelrod.strategy_transformers import (
@@ -182,11 +182,11 @@ class SneakyTitForTat(Player):
 
     def strategy(self, opponent: Player) -> Action:
         if len(self.history) < 2:
-            return "C"
+            return C
         if D not in opponent.history:
             return D
         if opponent.history[-1] == D and self.history[-2] == D:
-            return "C"
+            return C
         return opponent.history[-1]
 
 
@@ -297,7 +297,7 @@ def strategy(opponent: Player) -> Action:
         if not opponent.history:
             return C
         # Defects if two consecutive D in the opponent's last three moves
-        history_string = "".join(opponent.history[-3:])
+        history_string = actions_to_str(opponent.history[-3:])
         if 'DD' in history_string:
             return D
         # Otherwise cooperates

axelrod/strategy_transformers.py

@@ -130,11 +130,13 @@ def __repr__(self):
                 prefix = ': '
                 for arg in args:
                     try:
-                        arg = [player.name for player in arg]
-                    except TypeError:
-                        pass
+                        # Action has .name but should not be made into a list
+                        if not any(isinstance(el, Actions) for el in arg):
+                            arg = [player.name for player in arg]
                     except AttributeError:
                         pass
+                    except TypeError:
+                        pass
                     name = ''.join([name, prefix, str(arg)])
                     prefix = ', '
                 return name

axelrod/tests/integration/test_matches.py

@@ -52,10 +52,10 @@ def test_matches_with_det_player_for_stochastic_classes(self):
         p3 = axelrod.MemoryOnePlayer(four_vector=(1, 1, 1, 0))
 
         m = axelrod.Match((p1, p2), turns=3)
-        self.assertEqual(m.play(), [('C', 'C'), ('D', 'C'), ('D', 'D')])
+        self.assertEqual(m.play(), [(C, C), (D, C), (D, D)])
 
         m = axelrod.Match((p2, p3), turns=3)
-        self.assertEqual(m.play(), [('C', 'C'), ('C', 'C'), ('C', 'C')])
+        self.assertEqual(m.play(), [(C, C), (C, C), (C, C)])
 
         m = axelrod.Match((p1, p3), turns=3)
-        self.assertEqual(m.play(), [('C', 'C'), ('D', 'C'), ('D', 'C')])
+        self.assertEqual(m.play(), [(C, C), (D, C), (D, C)])

axelrod/tests/strategies/test_axelrod_first.py

@@ -367,7 +367,7 @@ def test_strategy(self):
 
 class TestSteinAndRapoport(TestPlayer):
 
-    name = "Stein and Rapoport: 0.05: ('D', 'D')"
+    name = "Stein and Rapoport: 0.05: (D, D)"
     player = axelrod.SteinAndRapoport
     expected_classifier = {
         'memory_depth': 15,

axelrod/tests/strategies/test_backstabber.py

@@ -11,7 +11,7 @@
 
 class TestBackStabber(TestPlayer):
 
-    name = "BackStabber: ('D', 'D')"
+    name = "BackStabber: (D, D)"
     player = axelrod.BackStabber
     expected_classifier = {
         'memory_depth': float('inf'),
@@ -56,7 +56,7 @@ class TestDoubleCrosser(TestBackStabber):
     The alternate strategy is triggered when opponent did not defect in the
     first 7 rounds, and 8 <= the current round <= 180.
     """
-    name = "DoubleCrosser: ('D', 'D')"
+    name = "DoubleCrosser: (D, D)"
     player = axelrod.DoubleCrosser
     expected_classifier = {
         'memory_depth': float('inf'),

axelrod/tests/strategies/test_cycler.py

@@ -68,7 +68,8 @@ def test_memory_depth_is_len_cycle_minus_one(self):
 
     def test_cycler_works_as_expected(self):
         expected = [(C, D), (D, D), (D, D), (C, D)] * 2
-        self.versus_test(axelrod.Defector(), expected_actions=expected, init_kwargs={'cycle': 'CDDC'})
+        self.versus_test(axelrod.Defector(), expected_actions=expected,
+                         init_kwargs={'cycle': 'CDDC'})
 
     def test_cycle_raises_value_error_on_bad_cycle_str(self):
         self.assertRaises(ValueError, Cycler, cycle='CdDC')

axelrod/tests/strategies/test_finite_state_machines.py

@@ -81,7 +81,7 @@ class TestSampleFSMPlayer(TestPlayer):
     """Test a few sample tables to make sure that the finite state machines are
     working as intended."""
 
-    name = "FSM Player: ((1, 'C', 1, 'C'), (1, 'D', 1, 'D')), 1, C"
+    name = "FSM Player: ((1, C, 1, C), (1, D, 1, D)), 1, C"
     player = axelrod.FSMPlayer
 
     expected_classifier = {
@@ -137,7 +137,7 @@ def test_wsls(self):
 
 
 class TestFSMPlayer(TestPlayer):
-    name = "FSM Player: ((1, 'C', 1, 'C'), (1, 'D', 1, 'D')), 1, C"
+    name = "FSM Player: ((1, C, 1, C), (1, D, 1, D)), 1, C"
     player = axelrod.FSMPlayer
 
     expected_classifier = {