From deab302214ed40265ff36f50d3a935ff620fe3f1 Mon Sep 17 00:00:00 2001
From: "T.J. Gaffney" <gaffney.tj@gmail.com>
Date: Tue, 31 Mar 2020 04:23:44 -0700
Subject: [PATCH 1/4] Create and use axl_filename

---
 axelrod/load_data_.py                          | 13 ++++++++++++-
 axelrod/plot.py                                |  3 ++-
 axelrod/tests/integration/test_tournament.py   |  7 ++++---
 axelrod/tests/unit/test_deterministic_cache.py |  7 ++++---
 axelrod/tests/unit/test_fingerprint.py         | 13 ++++++++-----
 axelrod/tests/unit/test_plot.py                |  3 ++-
 axelrod/tests/unit/test_resultset.py           |  5 +++--
 axelrod/tests/unit/test_tournament.py          |  9 ++++++---
 8 files changed, 41 insertions(+), 19 deletions(-)

diff --git a/axelrod/load_data_.py b/axelrod/load_data_.py
index 37d6ae677..812c0a208 100644
--- a/axelrod/load_data_.py
+++ b/axelrod/load_data_.py
@@ -1,8 +1,19 @@
-from typing import Dict, List, Tuple
+from typing import Dict, List, Text, Tuple
 
+import os
 import pkg_resources
 
 
+def axl_filename(axl_path: Text) -> Text:
+    """Get the path to Axelrod/<axl_path> from the working directory."""
+    # Working directory
+    dirname = os.path.dirname(__file__)
+
+    # We go up a dir because this code is located in Axelrod/axelrod and
+    # axl_path is from the top-level Axelrod dir.
+    return os.path.join(dirname, "..", axl_path)
+
+
 def load_file(filename: str, directory: str) -> List[List[str]]:
     """Loads a data file stored in the Axelrod library's data subdirectory,
     likely for parameters for a strategy."""
diff --git a/axelrod/plot.py b/axelrod/plot.py
index f2c1bcee1..2349a802f 100644
--- a/axelrod/plot.py
+++ b/axelrod/plot.py
@@ -8,6 +8,7 @@
 from numpy import arange, median, nan_to_num
 
 from .result_set import ResultSet
+from .load_data_ import axl_filename
 
 titleType = List[str]
 namesType = List[str]
@@ -323,7 +324,7 @@ def save_all_plots(
 
         for method, name in plots:
             f = getattr(self, method)(title="{} - {}".format(title_prefix, name))
-            f.savefig("{}_{}.{}".format(prefix, method, filetype))
+            f.savefig(axl_filename("{}_{}.{}".format(prefix, method, filetype)))
             plt.close(f)
 
             if progress_bar:
diff --git a/axelrod/tests/integration/test_tournament.py b/axelrod/tests/integration/test_tournament.py
index 28d505416..c03fa818f 100644
--- a/axelrod/tests/integration/test_tournament.py
+++ b/axelrod/tests/integration/test_tournament.py
@@ -4,6 +4,7 @@
 from hypothesis import given, settings
 
 import axelrod
+from axelrod.load_data_ import axl_filename
 from axelrod.strategy_transformers import FinalTransformer
 from axelrod.tests.property import tournaments
 
@@ -45,7 +46,7 @@ def setUpClass(cls):
     def test_big_tournaments(self, tournament):
         """A test to check that tournament runs with a sample of non-cheating
         strategies."""
-        filename = "test_outputs/test_tournament.csv"
+        filename = axl_filename("test_outputs/test_tournament.csv")
         self.assertIsNone(
             tournament.play(progress_bar=False, filename=filename, build_results=False)
         )
@@ -90,7 +91,7 @@ def test_repeat_tournament_deterministic(self):
                 turns=2,
                 repetitions=2,
             )
-            files.append("test_outputs/stochastic_tournament_{}.csv".format(_))
+            files.append(axl_filename("test_outputs/stochastic_tournament_{}.csv".format(_)))
             tournament.play(progress_bar=False, filename=files[-1], build_results=False)
         self.assertTrue(filecmp.cmp(files[0], files[1]))
 
@@ -113,7 +114,7 @@ def test_repeat_tournament_stochastic(self):
                 turns=2,
                 repetitions=2,
             )
-            files.append("test_outputs/stochastic_tournament_{}.csv".format(_))
+            files.append(axl_filename("test_outputs/stochastic_tournament_{}.csv".format(_)))
             tournament.play(progress_bar=False, filename=files[-1], build_results=False)
         self.assertTrue(filecmp.cmp(files[0], files[1]))
 
diff --git a/axelrod/tests/unit/test_deterministic_cache.py b/axelrod/tests/unit/test_deterministic_cache.py
index 8728787aa..4e2f46e41 100644
--- a/axelrod/tests/unit/test_deterministic_cache.py
+++ b/axelrod/tests/unit/test_deterministic_cache.py
@@ -3,6 +3,7 @@
 import unittest
 
 from axelrod import Action, Defector, DeterministicCache, Random, TitForTat
+from axelrod.load_data_ import axl_filename
 
 C, D = Action.C, Action.D
 
@@ -12,8 +13,8 @@ class TestDeterministicCache(unittest.TestCase):
     def setUpClass(cls):
         cls.test_key = (TitForTat(), Defector())
         cls.test_value = [(C, D), (D, D), (D, D)]
-        cls.test_save_file = "test_cache_save.txt"
-        cls.test_load_file = "test_cache_load.txt"
+        cls.test_save_file = axl_filename("test_outputs/test_cache_save.txt")
+        cls.test_load_file = axl_filename("test_outputs/test_cache_load.txt")
         test_data_to_pickle = {("Tit For Tat", "Defector"): [(C, D), (D, D), (D, D)]}
         cls.test_pickle = pickle.dumps(test_data_to_pickle)
 
@@ -92,7 +93,7 @@ def test_load(self):
         self.assertEqual(self.cache[self.test_key], self.test_value)
 
     def test_load_error_for_inccorect_format(self):
-        filename = "test_outputs/test.cache"
+        filename = axl_filename("test_outputs/test.cache")
         with open(filename, "wb") as io:
             pickle.dump(range(5), io)
 
diff --git a/axelrod/tests/unit/test_fingerprint.py b/axelrod/tests/unit/test_fingerprint.py
index bab8b5055..05cc287a4 100644
--- a/axelrod/tests/unit/test_fingerprint.py
+++ b/axelrod/tests/unit/test_fingerprint.py
@@ -9,6 +9,7 @@
 
 import axelrod as axl
 from axelrod.fingerprint import AshlockFingerprint, Point, TransitiveFingerprint
+from axelrod.load_data_ import axl_filename
 from axelrod.strategy_transformers import DualTransformer, JossAnnTransformer
 from axelrod.tests.property import strategy_lists
 
@@ -195,7 +196,7 @@ def test_temp_file_creation(self):
 
         RecordedMksTemp.reset_record()
         af = AshlockFingerprint(axl.TitForTat)
-        filename = "test_outputs/test_fingerprint.csv"
+        filename = axl_filename("test_outputs/test_fingerprint.csv")
 
         self.assertEqual(RecordedMksTemp.record, [])
 
@@ -211,7 +212,7 @@ def test_temp_file_creation(self):
         self.assertFalse(os.path.isfile(filename))
 
     def test_fingerprint_with_filename(self):
-        filename = "test_outputs/test_fingerprint.csv"
+        filename = axl_filename("test_outputs/test_fingerprint.csv")
         af = AshlockFingerprint(axl.TitForTat)
         af.fingerprint(
             turns=1, repetitions=1, step=0.5, progress_bar=False, filename=filename
@@ -425,7 +426,7 @@ def test_init_with_not_default_number(self):
         )
 
     def test_fingerprint_with_filename(self):
-        filename = "test_outputs/test_fingerprint.csv"
+        filename = axl_filename("test_outputs/test_fingerprint.csv")
         strategy = axl.TitForTat()
         tf = TransitiveFingerprint(strategy)
         tf.fingerprint(turns=1, repetitions=1, progress_bar=False, filename=filename)
@@ -437,7 +438,9 @@ def test_serial_fingerprint(self):
         strategy = axl.TitForTat()
         tf = TransitiveFingerprint(strategy)
         tf.fingerprint(
-            repetitions=1, progress_bar=False, filename="test_outputs/tran_fin.csv"
+            repetitions=1,
+            progress_bar=False,
+            filename=axl_filename("test_outputs/tran_fin.csv"),
         )
         self.assertEqual(tf.data.shape, (50, 50))
 
@@ -450,7 +453,7 @@ def test_parallel_fingerprint(self):
 
     def test_analyse_cooperation_ratio(self):
         tf = TransitiveFingerprint(axl.TitForTat)
-        filename = "test_outputs/test_fingerprint.csv"
+        filename = axl_filename("test_outputs/test_fingerprint.csv")
         with open(filename, "w") as f:
             f.write(
                 """Interaction index,Player index,Opponent index,Repetition,Player name,Opponent name,Actions
diff --git a/axelrod/tests/unit/test_plot.py b/axelrod/tests/unit/test_plot.py
index ddad0fef7..a48624d0f 100644
--- a/axelrod/tests/unit/test_plot.py
+++ b/axelrod/tests/unit/test_plot.py
@@ -2,6 +2,7 @@
 import unittest
 
 import axelrod
+from axelrod.load_data_ import axl_filename
 import matplotlib
 import matplotlib.pyplot as plt
 from numpy import mean
@@ -10,7 +11,7 @@
 class TestPlot(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
-        cls.filename = "test_outputs/test_results.csv"
+        cls.filename = axl_filename("test_outputs/test_results.csv")
 
         cls.players = [axelrod.Alternator(), axelrod.TitForTat(), axelrod.Defector()]
         cls.repetitions = 3
diff --git a/axelrod/tests/unit/test_resultset.py b/axelrod/tests/unit/test_resultset.py
index 9f5586811..37237d8fc 100644
--- a/axelrod/tests/unit/test_resultset.py
+++ b/axelrod/tests/unit/test_resultset.py
@@ -5,6 +5,7 @@
 import axelrod
 import axelrod.interaction_utils as iu
 import pandas as pd
+from axelrod.load_data_ import axl_filename
 from axelrod.result_set import create_counter_dict
 from axelrod.tests.property import prob_end_tournaments, tournaments
 from numpy import mean, nanmedian, std
@@ -19,7 +20,7 @@ class TestResultSet(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = "test_outputs/test_results.csv"
+        cls.filename = axl_filename("test_outputs/test_results.csv")
 
         cls.players = [axelrod.Alternator(), axelrod.TitForTat(), axelrod.Defector()]
         cls.repetitions = 3
@@ -647,7 +648,7 @@ class TestResultSetSpatialStructure(TestResultSet):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = "test_outputs/test_results_spatial.csv"
+        cls.filename = axl_filename("test_outputs/test_results_spatial.csv")
         cls.players = [axelrod.Alternator(), axelrod.TitForTat(), axelrod.Defector()]
         cls.turns = 5
         cls.edges = [(0, 1), (0, 2)]
diff --git a/axelrod/tests/unit/test_tournament.py b/axelrod/tests/unit/test_tournament.py
index 27f994f09..c1a096ff6 100644
--- a/axelrod/tests/unit/test_tournament.py
+++ b/axelrod/tests/unit/test_tournament.py
@@ -12,6 +12,7 @@
 from unittest.mock import MagicMock, patch
 
 import axelrod
+from axelrod.load_data_ import axl_filename
 import numpy as np
 import pandas as pd
 from axelrod.tests.property import (
@@ -88,7 +89,7 @@ def setUpClass(cls):
             [200, 200, 1, 200, 200],
         ]
 
-        cls.filename = "test_outputs/test_tournament.csv"
+        cls.filename = axl_filename("test_outputs/test_tournament.csv")
 
     def setUp(self):
         self.test_tournament = axelrod.Tournament(
@@ -733,7 +734,9 @@ def test_write_to_csv_with_results(self):
         )
         tournament.play(filename=self.filename, progress_bar=False)
         df = pd.read_csv(self.filename)
-        expected_df = pd.read_csv("test_outputs/expected_test_tournament.csv")
+        expected_df = pd.read_csv(
+            axl_filename("test_outputs/expected_test_tournament.csv")
+        )
         self.assertTrue(df.equals(expected_df))
 
     def test_write_to_csv_without_results(self):
@@ -747,7 +750,7 @@ def test_write_to_csv_without_results(self):
         tournament.play(filename=self.filename, progress_bar=False, build_results=False)
         df = pd.read_csv(self.filename)
         expected_df = pd.read_csv(
-            "test_outputs/expected_test_tournament_no_results.csv"
+            axl_filename("test_outputs/expected_test_tournament_no_results.csv")
         )
         self.assertTrue(df.equals(expected_df))
 

From 21a5a8f9687388e4923668b6facc633cd740df49 Mon Sep 17 00:00:00 2001
From: "T.J. Gaffney" <gaffney.tj@gmail.com>
Date: Sat, 4 Apr 2020 12:50:09 -0700
Subject: [PATCH 2/4] Add test_axl_filename

---
 axelrod/tests/unit/test_load_data.py | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 axelrod/tests/unit/test_load_data.py

diff --git a/axelrod/tests/unit/test_load_data.py b/axelrod/tests/unit/test_load_data.py
new file mode 100644
index 000000000..52119f3ec
--- /dev/null
+++ b/axelrod/tests/unit/test_load_data.py
@@ -0,0 +1,15 @@
+import os
+import unittest
+
+from axelrod.load_data_ import axl_filename
+
+
+class TestLoadData(unittest.TestCase):
+    def test_axl_filename(self):
+        actual_fn = axl_filename("axelrod/strategies/titfortat.py")
+
+        # First go from "unit" up to "tests", then up to "axelrod"
+        dirname = os.path.dirname(__file__)
+        expected_fn = os.path.join(dirname, "../../strategies/titfortat.py")
+
+        self.assertTrue(os.path.samefile(actual_fn, expected_fn))

From f5bad9f8896dbbe697418f611a142df0d538ab4c Mon Sep 17 00:00:00 2001
From: "T.J. Gaffney" <gaffney.tj@gmail.com>
Date: Mon, 6 Apr 2020 02:19:41 -0700
Subject: [PATCH 3/4] Update axl_filename to use pathlib and take multiple
 arguments

---
 axelrod/load_data_.py                         | 27 ++++++++++++-----
 axelrod/tests/integration/test_tournament.py  | 30 +++++++++++--------
 .../tests/unit/test_deterministic_cache.py    |  6 ++--
 axelrod/tests/unit/test_fingerprint.py        |  8 ++---
 axelrod/tests/unit/test_plot.py               |  2 +-
 axelrod/tests/unit/test_resultset.py          |  2 +-
 axelrod/tests/unit/test_tournament.py         |  6 ++--
 requirements.txt                              |  1 +
 8 files changed, 50 insertions(+), 32 deletions(-)

diff --git a/axelrod/load_data_.py b/axelrod/load_data_.py
index 812c0a208..26b309127 100644
--- a/axelrod/load_data_.py
+++ b/axelrod/load_data_.py
@@ -1,17 +1,28 @@
+import pathlib
 from typing import Dict, List, Text, Tuple
 
-import os
 import pkg_resources
 
 
-def axl_filename(axl_path: Text) -> Text:
-    """Get the path to Axelrod/<axl_path> from the working directory."""
-    # Working directory
-    dirname = os.path.dirname(__file__)
+def axl_filename(*axl_path: Text) -> Text:
+    """Given a path under Axelrod/, return absolute filepath.
 
-    # We go up a dir because this code is located in Axelrod/axelrod and
-    # axl_path is from the top-level Axelrod dir.
-    return os.path.join(dirname, "..", axl_path)
+    Parameters
+    ----------
+    axl_path
+        Path to file located under top-level Axelrod directory, with file names
+        separated at "/".  For example, to get the path to "Axelrod/xxx/yyy.py"
+        call this function with axl_filename("xxx", "yyy.py").
+
+    Returns
+    -------
+        Absolute path to the given path.
+    """
+    # We go up a dir because this code is located in Axelrod/axelrod.
+    path = pathlib.Path(__file__).resolve().parent.parent
+    for p in axl_path:
+        path = path / p
+    return str(path)
 
 
 def load_file(filename: str, directory: str) -> List[List[str]]:
diff --git a/axelrod/tests/integration/test_tournament.py b/axelrod/tests/integration/test_tournament.py
index c03fa818f..df986c02b 100644
--- a/axelrod/tests/integration/test_tournament.py
+++ b/axelrod/tests/integration/test_tournament.py
@@ -33,20 +33,22 @@ def setUpClass(cls):
         ]
         cls.expected_outcome.sort()
 
-    @given(tournaments(
-        strategies=axelrod.short_run_time_strategies,
-        min_size=10,
-        max_size=30,
-        min_turns=2,
-        max_turns=210,
-        min_repetitions=1,
-        max_repetitions=4,
-    ))
+    @given(
+        tournaments(
+            strategies=axelrod.short_run_time_strategies,
+            min_size=10,
+            max_size=30,
+            min_turns=2,
+            max_turns=210,
+            min_repetitions=1,
+            max_repetitions=4,
+        )
+    )
     @settings(max_examples=1)
     def test_big_tournaments(self, tournament):
         """A test to check that tournament runs with a sample of non-cheating
         strategies."""
-        filename = axl_filename("test_outputs/test_tournament.csv")
+        filename = axl_filename("test_outputs", "test_tournament.csv")
         self.assertIsNone(
             tournament.play(progress_bar=False, filename=filename, build_results=False)
         )
@@ -91,7 +93,9 @@ def test_repeat_tournament_deterministic(self):
                 turns=2,
                 repetitions=2,
             )
-            files.append(axl_filename("test_outputs/stochastic_tournament_{}.csv".format(_)))
+            files.append(
+                axl_filename("test_outputs", "stochastic_tournament_{}.csv".format(_))
+            )
             tournament.play(progress_bar=False, filename=files[-1], build_results=False)
         self.assertTrue(filecmp.cmp(files[0], files[1]))
 
@@ -114,7 +118,9 @@ def test_repeat_tournament_stochastic(self):
                 turns=2,
                 repetitions=2,
             )
-            files.append(axl_filename("test_outputs/stochastic_tournament_{}.csv".format(_)))
+            files.append(
+                axl_filename("test_outputs", "stochastic_tournament_{}.csv".format(_))
+            )
             tournament.play(progress_bar=False, filename=files[-1], build_results=False)
         self.assertTrue(filecmp.cmp(files[0], files[1]))
 
diff --git a/axelrod/tests/unit/test_deterministic_cache.py b/axelrod/tests/unit/test_deterministic_cache.py
index 4e2f46e41..8d5d3fcd6 100644
--- a/axelrod/tests/unit/test_deterministic_cache.py
+++ b/axelrod/tests/unit/test_deterministic_cache.py
@@ -13,8 +13,8 @@ class TestDeterministicCache(unittest.TestCase):
     def setUpClass(cls):
         cls.test_key = (TitForTat(), Defector())
         cls.test_value = [(C, D), (D, D), (D, D)]
-        cls.test_save_file = axl_filename("test_outputs/test_cache_save.txt")
-        cls.test_load_file = axl_filename("test_outputs/test_cache_load.txt")
+        cls.test_save_file = axl_filename("test_outputs", "test_cache_save.txt")
+        cls.test_load_file = axl_filename("test_outputs", "test_cache_load.txt")
         test_data_to_pickle = {("Tit For Tat", "Defector"): [(C, D), (D, D), (D, D)]}
         cls.test_pickle = pickle.dumps(test_data_to_pickle)
 
@@ -93,7 +93,7 @@ def test_load(self):
         self.assertEqual(self.cache[self.test_key], self.test_value)
 
     def test_load_error_for_inccorect_format(self):
-        filename = axl_filename("test_outputs/test.cache")
+        filename = axl_filename("test_outputs", "test.cache")
         with open(filename, "wb") as io:
             pickle.dump(range(5), io)
 
diff --git a/axelrod/tests/unit/test_fingerprint.py b/axelrod/tests/unit/test_fingerprint.py
index 05cc287a4..c0a225209 100644
--- a/axelrod/tests/unit/test_fingerprint.py
+++ b/axelrod/tests/unit/test_fingerprint.py
@@ -212,7 +212,7 @@ def test_temp_file_creation(self):
         self.assertFalse(os.path.isfile(filename))
 
     def test_fingerprint_with_filename(self):
-        filename = axl_filename("test_outputs/test_fingerprint.csv")
+        filename = axl_filename("test_outputs", "test_fingerprint.csv")
         af = AshlockFingerprint(axl.TitForTat)
         af.fingerprint(
             turns=1, repetitions=1, step=0.5, progress_bar=False, filename=filename
@@ -426,7 +426,7 @@ def test_init_with_not_default_number(self):
         )
 
     def test_fingerprint_with_filename(self):
-        filename = axl_filename("test_outputs/test_fingerprint.csv")
+        filename = axl_filename("test_outputs", "test_fingerprint.csv")
         strategy = axl.TitForTat()
         tf = TransitiveFingerprint(strategy)
         tf.fingerprint(turns=1, repetitions=1, progress_bar=False, filename=filename)
@@ -440,7 +440,7 @@ def test_serial_fingerprint(self):
         tf.fingerprint(
             repetitions=1,
             progress_bar=False,
-            filename=axl_filename("test_outputs/tran_fin.csv"),
+            filename=axl_filename("test_outputs", "tran_fin.csv"),
         )
         self.assertEqual(tf.data.shape, (50, 50))
 
@@ -453,7 +453,7 @@ def test_parallel_fingerprint(self):
 
     def test_analyse_cooperation_ratio(self):
         tf = TransitiveFingerprint(axl.TitForTat)
-        filename = axl_filename("test_outputs/test_fingerprint.csv")
+        filename = axl_filename("test_outputs", "test_fingerprint.csv")
         with open(filename, "w") as f:
             f.write(
                 """Interaction index,Player index,Opponent index,Repetition,Player name,Opponent name,Actions
diff --git a/axelrod/tests/unit/test_plot.py b/axelrod/tests/unit/test_plot.py
index a48624d0f..52ce0d45e 100644
--- a/axelrod/tests/unit/test_plot.py
+++ b/axelrod/tests/unit/test_plot.py
@@ -11,7 +11,7 @@
 class TestPlot(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
-        cls.filename = axl_filename("test_outputs/test_results.csv")
+        cls.filename = axl_filename("test_outputs", "test_results.csv")
 
         cls.players = [axelrod.Alternator(), axelrod.TitForTat(), axelrod.Defector()]
         cls.repetitions = 3
diff --git a/axelrod/tests/unit/test_resultset.py b/axelrod/tests/unit/test_resultset.py
index 37237d8fc..addd87236 100644
--- a/axelrod/tests/unit/test_resultset.py
+++ b/axelrod/tests/unit/test_resultset.py
@@ -648,7 +648,7 @@ class TestResultSetSpatialStructure(TestResultSet):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = axl_filename("test_outputs/test_results_spatial.csv")
+        cls.filename = axl_filename("test_outputs", "test_results_spatial.csv")
         cls.players = [axelrod.Alternator(), axelrod.TitForTat(), axelrod.Defector()]
         cls.turns = 5
         cls.edges = [(0, 1), (0, 2)]
diff --git a/axelrod/tests/unit/test_tournament.py b/axelrod/tests/unit/test_tournament.py
index c1a096ff6..4f8a1ff51 100644
--- a/axelrod/tests/unit/test_tournament.py
+++ b/axelrod/tests/unit/test_tournament.py
@@ -89,7 +89,7 @@ def setUpClass(cls):
             [200, 200, 1, 200, 200],
         ]
 
-        cls.filename = axl_filename("test_outputs/test_tournament.csv")
+        cls.filename = axl_filename("test_outputs", "test_tournament.csv")
 
     def setUp(self):
         self.test_tournament = axelrod.Tournament(
@@ -735,7 +735,7 @@ def test_write_to_csv_with_results(self):
         tournament.play(filename=self.filename, progress_bar=False)
         df = pd.read_csv(self.filename)
         expected_df = pd.read_csv(
-            axl_filename("test_outputs/expected_test_tournament.csv")
+            axl_filename("test_outputs", "expected_test_tournament.csv")
         )
         self.assertTrue(df.equals(expected_df))
 
@@ -750,7 +750,7 @@ def test_write_to_csv_without_results(self):
         tournament.play(filename=self.filename, progress_bar=False, build_results=False)
         df = pd.read_csv(self.filename)
         expected_df = pd.read_csv(
-            axl_filename("test_outputs/expected_test_tournament_no_results.csv")
+            axl_filename("test_outputs", "expected_test_tournament_no_results.csv")
         )
         self.assertTrue(df.equals(expected_df))
 
diff --git a/requirements.txt b/requirements.txt
index 5c3b872b2..98c84f82d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,6 +5,7 @@ hypothesis==3.2
 matplotlib>=2.0.0
 numpy>=1.9.2
 pandas>=0.18.1
+pathlib>=1.0.1
 prompt-toolkit>=1.0.7
 scipy>=0.19.0
 toolz>=0.8.0

From 25514fcf064949d1b62b3aa1d31e293c78c9f518 Mon Sep 17 00:00:00 2001
From: "T.J. Gaffney" <gaffney.tj@gmail.com>
Date: Mon, 6 Apr 2020 04:50:48 -0700
Subject: [PATCH 4/4] Change axl_filename to take a pathlib.Path

---
 axelrod/load_data_.py                         | 14 ++++-----
 axelrod/plot.py                               |  4 ++-
 axelrod/tests/integration/test_tournament.py  | 14 ++++-----
 .../tests/unit/test_deterministic_cache.py    | 10 +++++--
 axelrod/tests/unit/test_fingerprint.py        | 19 +++++++-----
 axelrod/tests/unit/test_load_data.py          |  4 ++-
 axelrod/tests/unit/test_plot.py               |  4 ++-
 axelrod/tests/unit/test_resultset.py          | 13 +++++---
 axelrod/tests/unit/test_tournament.py         | 30 +++++++------------
 9 files changed, 59 insertions(+), 53 deletions(-)

diff --git a/axelrod/load_data_.py b/axelrod/load_data_.py
index 26b309127..ac29250fd 100644
--- a/axelrod/load_data_.py
+++ b/axelrod/load_data_.py
@@ -4,25 +4,21 @@
 import pkg_resources
 
 
-def axl_filename(*axl_path: Text) -> Text:
+def axl_filename(path: pathlib.Path) -> pathlib.Path:
     """Given a path under Axelrod/, return absolute filepath.
 
     Parameters
     ----------
     axl_path
-        Path to file located under top-level Axelrod directory, with file names
-        separated at "/".  For example, to get the path to "Axelrod/xxx/yyy.py"
-        call this function with axl_filename("xxx", "yyy.py").
+        A pathlib.Path object with the relative directory under Axelrod/
 
     Returns
     -------
-        Absolute path to the given path.
+        A pathlib.Path object with the absolute directory.
     """
     # We go up a dir because this code is located in Axelrod/axelrod.
-    path = pathlib.Path(__file__).resolve().parent.parent
-    for p in axl_path:
-        path = path / p
-    return str(path)
+    axl_path = pathlib.Path(__file__).resolve().parent.parent
+    return axl_path / path
 
 
 def load_file(filename: str, directory: str) -> List[List[str]]:
diff --git a/axelrod/plot.py b/axelrod/plot.py
index 2349a802f..edc596529 100644
--- a/axelrod/plot.py
+++ b/axelrod/plot.py
@@ -4,6 +4,7 @@
 import matplotlib
 import matplotlib.pyplot as plt
 import matplotlib.transforms as transforms
+import pathlib
 import tqdm
 from numpy import arange, median, nan_to_num
 
@@ -324,7 +325,8 @@ def save_all_plots(
 
         for method, name in plots:
             f = getattr(self, method)(title="{} - {}".format(title_prefix, name))
-            f.savefig(axl_filename("{}_{}.{}".format(prefix, method, filetype)))
+            path = pathlib.Path("{}_{}.{}".format(prefix, method, filetype))
+            f.savefig(axl_filename(path))
             plt.close(f)
 
             if progress_bar:
diff --git a/axelrod/tests/integration/test_tournament.py b/axelrod/tests/integration/test_tournament.py
index b4cb21d92..3e031450e 100644
--- a/axelrod/tests/integration/test_tournament.py
+++ b/axelrod/tests/integration/test_tournament.py
@@ -1,6 +1,7 @@
 import unittest
 
 import filecmp
+import pathlib
 
 import axelrod as axl
 from axelrod.load_data_ import axl_filename
@@ -49,7 +50,8 @@ def setUpClass(cls):
     def test_big_tournaments(self, tournament):
         """A test to check that tournament runs with a sample of non-cheating
         strategies."""
-        filename = axl_filename("test_outputs", "test_tournament.csv")
+        path = pathlib.Path("test_outputs/test_tournament.csv")
+        filename = axl_filename(path)
         self.assertIsNone(
             tournament.play(progress_bar=False, filename=filename, build_results=False)
         )
@@ -94,9 +96,8 @@ def test_repeat_tournament_deterministic(self):
                 turns=2,
                 repetitions=2,
             )
-            files.append(
-                axl_filename("test_outputs", "stochastic_tournament_{}.csv".format(_))
-            )
+            path = pathlib.Path("test_outputs/stochastic_tournament_{}.csv".format(_))
+            files.append(axl_filename(path))
             tournament.play(progress_bar=False, filename=files[-1], build_results=False)
         self.assertTrue(filecmp.cmp(files[0], files[1]))
 
@@ -119,9 +120,8 @@ def test_repeat_tournament_stochastic(self):
                 turns=2,
                 repetitions=2,
             )
-            files.append(
-                axl_filename("test_outputs", "stochastic_tournament_{}.csv".format(_))
-            )
+            path = pathlib.Path("test_outputs/stochastic_tournament_{}.csv".format(_))
+            files.append(axl_filename(path))
             tournament.play(progress_bar=False, filename=files[-1], build_results=False)
         self.assertTrue(filecmp.cmp(files[0], files[1]))
 
diff --git a/axelrod/tests/unit/test_deterministic_cache.py b/axelrod/tests/unit/test_deterministic_cache.py
index 3278e1af0..82d11904c 100644
--- a/axelrod/tests/unit/test_deterministic_cache.py
+++ b/axelrod/tests/unit/test_deterministic_cache.py
@@ -1,5 +1,6 @@
 import unittest
 import os
+import pathlib
 import pickle
 
 import axelrod as axl
@@ -13,8 +14,10 @@ class TestDeterministicCache(unittest.TestCase):
     def setUpClass(cls):
         cls.test_key = (axl.TitForTat(), axl.Defector())
         cls.test_value = [(C, D), (D, D), (D, D)]
-        cls.test_save_file = axl_filename("test_outputs", "test_cache_save.txt")
-        cls.test_load_file = axl_filename("test_outputs", "test_cache_load.txt")
+        save_path = pathlib.Path("test_outputs/test_cache_save.txt")
+        cls.test_save_file = axl_filename(save_path)
+        load_path = pathlib.Path("test_outputs/test_cache_load.txt")
+        cls.test_load_file = axl_filename(load_path)
         test_data_to_pickle = {("Tit For Tat", "Defector"): [(C, D), (D, D), (D, D)]}
         cls.test_pickle = pickle.dumps(test_data_to_pickle)
 
@@ -93,7 +96,8 @@ def test_load(self):
         self.assertEqual(self.cache[self.test_key], self.test_value)
 
     def test_load_error_for_inccorect_format(self):
-        filename = axl_filename("test_outputs", "test.cache")
+        path = pathlib.Path("test_outputs/test.cache")
+        filename = axl_filename(path)
         with open(filename, "wb") as io:
             pickle.dump(range(5), io)
 
diff --git a/axelrod/tests/unit/test_fingerprint.py b/axelrod/tests/unit/test_fingerprint.py
index b8f481307..f60a93e7a 100644
--- a/axelrod/tests/unit/test_fingerprint.py
+++ b/axelrod/tests/unit/test_fingerprint.py
@@ -2,12 +2,10 @@
 from unittest.mock import patch
 
 import os
-
 from tempfile import mkstemp
-
 import matplotlib.pyplot
-
 import numpy as np
+import pathlib
 
 import axelrod as axl
 from axelrod.fingerprint import AshlockFingerprint, Point, TransitiveFingerprint
@@ -201,7 +199,8 @@ def test_temp_file_creation(self):
 
         RecordedMksTemp.reset_record()
         af = AshlockFingerprint(axl.TitForTat)
-        filename = axl_filename("test_outputs/test_fingerprint.csv")
+        path = pathlib.Path("test_outputs/test_fingerprint.csv")
+        filename = axl_filename(path)
 
         self.assertEqual(RecordedMksTemp.record, [])
 
@@ -217,7 +216,8 @@ def test_temp_file_creation(self):
         self.assertFalse(os.path.isfile(filename))
 
     def test_fingerprint_with_filename(self):
-        filename = axl_filename("test_outputs", "test_fingerprint.csv")
+        path = pathlib.Path("test_outputs/test_fingerprint.csv")
+        filename = axl_filename(path)
         af = AshlockFingerprint(axl.TitForTat)
         af.fingerprint(
             turns=1, repetitions=1, step=0.5, progress_bar=False, filename=filename
@@ -431,7 +431,8 @@ def test_init_with_not_default_number(self):
         )
 
     def test_fingerprint_with_filename(self):
-        filename = axl_filename("test_outputs", "test_fingerprint.csv")
+        path = pathlib.Path("test_outputs/test_fingerprint.csv")
+        filename = axl_filename(path)
         strategy = axl.TitForTat()
         tf = TransitiveFingerprint(strategy)
         tf.fingerprint(turns=1, repetitions=1, progress_bar=False, filename=filename)
@@ -442,10 +443,11 @@ def test_fingerprint_with_filename(self):
     def test_serial_fingerprint(self):
         strategy = axl.TitForTat()
         tf = TransitiveFingerprint(strategy)
+        path = pathlib.Path("test_outputs/test_fingerprint.csv")
         tf.fingerprint(
             repetitions=1,
             progress_bar=False,
-            filename=axl_filename("test_outputs", "tran_fin.csv"),
+            filename=axl_filename(path),
         )
         self.assertEqual(tf.data.shape, (50, 50))
 
@@ -458,7 +460,8 @@ def test_parallel_fingerprint(self):
 
     def test_analyse_cooperation_ratio(self):
         tf = TransitiveFingerprint(axl.TitForTat)
-        filename = axl_filename("test_outputs", "test_fingerprint.csv")
+        path = pathlib.Path("test_outputs/test_fingerprint.csv")
+        filename = axl_filename(path)
         with open(filename, "w") as f:
             f.write(
                 """Interaction index,Player index,Opponent index,Repetition,Player name,Opponent name,Actions
diff --git a/axelrod/tests/unit/test_load_data.py b/axelrod/tests/unit/test_load_data.py
index 52119f3ec..6dd880335 100644
--- a/axelrod/tests/unit/test_load_data.py
+++ b/axelrod/tests/unit/test_load_data.py
@@ -1,4 +1,5 @@
 import os
+import pathlib
 import unittest
 
 from axelrod.load_data_ import axl_filename
@@ -6,7 +7,8 @@
 
 class TestLoadData(unittest.TestCase):
     def test_axl_filename(self):
-        actual_fn = axl_filename("axelrod/strategies/titfortat.py")
+        path = pathlib.Path("axelrod/strategies/titfortat.py")
+        actual_fn = axl_filename(path)
 
         # First go from "unit" up to "tests", then up to "axelrod"
         dirname = os.path.dirname(__file__)
diff --git a/axelrod/tests/unit/test_plot.py b/axelrod/tests/unit/test_plot.py
index 90d4a083e..89d40d8d9 100644
--- a/axelrod/tests/unit/test_plot.py
+++ b/axelrod/tests/unit/test_plot.py
@@ -3,6 +3,7 @@
 import tempfile
 import matplotlib
 import matplotlib.pyplot as plt
+import pathlib
 
 from numpy import mean
 
@@ -13,7 +14,8 @@
 class TestPlot(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
-        cls.filename = axl_filename("test_outputs", "test_results.csv")
+        path = pathlib.Path("test_outputs/test_results.csv")
+        cls.filename = axl_filename(path)
 
         cls.players = [axl.Alternator(), axl.TitForTat(), axl.Defector()]
         cls.repetitions = 3
diff --git a/axelrod/tests/unit/test_resultset.py b/axelrod/tests/unit/test_resultset.py
index 1d988c615..8bd0be3af 100644
--- a/axelrod/tests/unit/test_resultset.py
+++ b/axelrod/tests/unit/test_resultset.py
@@ -4,6 +4,7 @@
 import pandas as pd
 from dask.dataframe.core import DataFrame
 from numpy import mean, nanmedian, std
+import pathlib
 
 import axelrod as axl
 from axelrod.load_data_ import axl_filename
@@ -19,7 +20,8 @@ class TestResultSet(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = axl_filename("test_outputs", "test_results.csv")
+        path = pathlib.Path("test_outputs/test_results.csv")
+        cls.filename = str(axl_filename(path))
 
         cls.players = [axl.Alternator(), axl.TitForTat(), axl.Defector()]
         cls.repetitions = 3
@@ -677,7 +679,8 @@ class TestResultSetSpatialStructure(TestResultSet):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = axl_filename("test_outputs", "test_results_spatial.csv")
+        path = pathlib.Path("test_outputs/test_results_spatial.csv")
+        cls.filename = str(axl_filename(path))
         cls.players = [axl.Alternator(), axl.TitForTat(), axl.Defector()]
         cls.turns = 5
         cls.edges = [(0, 1), (0, 2)]
@@ -857,7 +860,8 @@ class TestResultSetSpatialStructureTwo(TestResultSetSpatialStructure):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = axl_filename("test_outputs", "test_results_spatial_two.csv")
+        path = pathlib.Path("test_outputs/test_results_spatial_two.csv")
+        cls.filename = str(axl_filename(path))
         cls.players = [
             axl.Alternator(),
             axl.TitForTat(),
@@ -1058,7 +1062,8 @@ class TestResultSetSpatialStructureThree(TestResultSetSpatialStructure):
     @classmethod
     def setUpClass(cls):
 
-        cls.filename = axl_filename("test_outputs", "test_results_spatial_three.csv")
+        path = pathlib.Path("test_outputs/test_results_spatial_three.csv")
+        cls.filename = str(axl_filename(path))
         cls.players = [
             axl.Alternator(),
             axl.TitForTat(),
diff --git a/axelrod/tests/unit/test_tournament.py b/axelrod/tests/unit/test_tournament.py
index 0ad0799a2..70410457a 100644
--- a/axelrod/tests/unit/test_tournament.py
+++ b/axelrod/tests/unit/test_tournament.py
@@ -7,6 +7,7 @@
 import io
 import logging
 import os
+import pathlib
 import pickle
 import warnings
 from multiprocessing import Queue, cpu_count
@@ -90,7 +91,8 @@ def setUpClass(cls):
             [200, 200, 1, 200, 200],
         ]
 
-        cls.filename = axl_filename("test_outputs", "test_tournament.csv")
+        path = pathlib.Path("test_outputs/test_tournament.csv")
+        cls.filename = axl_filename(path)
 
     def setUp(self):
         self.test_tournament = axl.Tournament(
@@ -110,9 +112,7 @@ def test_init(self):
             noise=0.2,
         )
         self.assertEqual(len(tournament.players), len(test_strategies))
-        self.assertIsInstance(
-            tournament.players[0].match_attributes["game"], axl.Game
-        )
+        self.assertIsInstance(tournament.players[0].match_attributes["game"], axl.Game)
         self.assertEqual(tournament.game.score((C, C)), (3, 3))
         self.assertEqual(tournament.turns, self.test_turns)
         self.assertEqual(tournament.repetitions, 10)
@@ -415,9 +415,7 @@ def test_progress_bar_play_parallel(self):
     # these two examples were identified by hypothesis.
     @example(
         tournament=axl.Tournament(
-            players=[axl.BackStabber(), axl.MindReader()],
-            turns=2,
-            repetitions=1,
+            players=[axl.BackStabber(), axl.MindReader()], turns=2, repetitions=1,
         )
     )
     @example(
@@ -735,9 +733,8 @@ def test_write_to_csv_with_results(self):
         )
         tournament.play(filename=self.filename, progress_bar=False)
         df = pd.read_csv(self.filename)
-        expected_df = pd.read_csv(
-            axl_filename("test_outputs", "expected_test_tournament.csv")
-        )
+        path = pathlib.Path("test_outputs/expected_test_tournament.csv")
+        expected_df = pd.read_csv(axl_filename(path))
         self.assertTrue(df.equals(expected_df))
 
     def test_write_to_csv_without_results(self):
@@ -750,9 +747,8 @@ def test_write_to_csv_without_results(self):
         )
         tournament.play(filename=self.filename, progress_bar=False, build_results=False)
         df = pd.read_csv(self.filename)
-        expected_df = pd.read_csv(
-            axl_filename("test_outputs", "expected_test_tournament_no_results.csv")
-        )
+        path = pathlib.Path("test_outputs/expected_test_tournament_no_results.csv")
+        expected_df = pd.read_csv(axl_filename(path))
         self.assertTrue(df.equals(expected_df))
 
 
@@ -808,16 +804,12 @@ def test_init(self):
     # these two examples were identified by hypothesis.
     @example(
         tournament=axl.Tournament(
-            players=[axl.BackStabber(), axl.MindReader()],
-            prob_end=0.2,
-            repetitions=1,
+            players=[axl.BackStabber(), axl.MindReader()], prob_end=0.2, repetitions=1,
         )
     )
     @example(
         tournament=axl.Tournament(
-            players=[axl.ThueMorse(), axl.MindReader()],
-            prob_end=0.2,
-            repetitions=1,
+            players=[axl.ThueMorse(), axl.MindReader()], prob_end=0.2, repetitions=1,
         )
     )
     def test_property_serial_play(self, tournament):