Lookup classifiers from yaml when no trivial initializer

Author: gaffney2010

axelrod/classifier.py

@@ -179,13 +179,22 @@ def __getitem__(
 
         def classify_player_for_this_classifier(
             player: Union[Player, Type[Player]]) -> Any:
+            def try_lookup() -> Any:
+                try:
+                    player_classifiers = cls.all_player_dicts[player.name]
+                except:
+                    return None
+
+                return player_classifiers.get(key, None)
+
             # If the passed player is not an instance, then try to initialize an
             # instance without arguments.
             if not isinstance(player, Player):
                 try:
                     player = player()
                 except:
-                    pass
+                    # Can't use the instances, so just go by name.
+                    return try_lookup()
 
             # Factory-generated players won't exist in the table.  As well, some
             # players, like Random, may change classifiers at construction time;
@@ -194,12 +203,8 @@ def classify_player_for_this_classifier(
             if key in player.classifier:
                 return player.classifier[key]
 
-            try:
-                player_classifiers = cls.all_player_dicts[player.name]
-            except:
-                return None
-
-            return player_classifiers.get(key, None)
+            # Try to find the name in the all_player_dicts, read from disk.
+            return try_lookup()
 
         return classify_player_for_this_classifier
 

axelrod/tests/unit/test_classification.py

@@ -2,7 +2,7 @@
 
 import os
 import unittest
-from typing import Text
+from typing import Any, Text
 
 import yaml
 
@@ -27,6 +27,20 @@ class TitForTatWithEmptyClassifier(Player):
     classifier = {}
 
 
+class TitForTatWithNonTrivialInitialzer(Player):
+    """
+    Same name as TitForTat, but with empty classifier.
+    """
+
+    def __init__(self, x: Any):
+        self.x = x  # Doesn't actually do anything.
+        super(TitForTatWithNonTrivialInitialzer).__init__()
+
+    # Classifiers are looked up by name, so only the name matters.
+    name = "Tit For Tat"
+    classifier = {}
+
+
 class TestClassification(unittest.TestCase):
     def test_classifier_build(self):
         dirname = os.path.dirname(__file__)
@@ -67,6 +81,9 @@ def test_key_error_on_uknown_classifier(self):
     def test_will_lookup_key_in_dict(self):
         self.assertEqual(Classifiers["memory_depth"](TitForTatWithEmptyClassifier), 1)
 
+    def test_will_lookup_key_for_classes_that_cant_init(self):
+        self.assertEqual(Classifiers["memory_depth"](TitForTatWithNonTrivialInitialzer), 1)
+
     def test_known_classifiers(self):
         # A set of dimensions that are known to have been fully applied
         known_keys = [