Fix helper function tests

tests/torchtune/training/checkpointing/test_checkpointer_utils.py

@@ -4,6 +4,7 @@
 # This source code is licensed under the BSD-style license found in the
 # LICENSE file in the root directory of this source tree.
 
+import os
 from copy import deepcopy
 from pathlib import Path
 
@@ -278,88 +279,85 @@ def test_output_dir_ckpt_dir_few_levels_down(self):
 class TestGetAllCheckpointsInDir:
     """Series of tests for the ``get_all_checkpoints_in_dir`` function."""
 
-    def test_get_all_ckpts_simple(self, tmp_dir):
-        ckpt_dir_0 = tmp_dir / "epoch_0"
+    def test_get_all_ckpts_simple(self, tmpdir):
+        tmpdir = Path(tmpdir)
+        ckpt_dir_0 = tmpdir / "epoch_0"
         ckpt_dir_0.mkdir(parents=True, exist_ok=True)
 
-        ckpt_dir_1 = tmp_dir / "epoch_1"
-        ckpt_dir_1.mkdir(parents=True, exist_ok=True)
+        ckpt_dir_1 = tmpdir / "epoch_1"
+        ckpt_dir_1.mkdir()
 
-        all_ckpts = get_all_checkpoints_in_dir(tmp_dir)
+        all_ckpts = get_all_checkpoints_in_dir(tmpdir)
         assert len(all_ckpts) == 2
         assert all_ckpts == [ckpt_dir_0, ckpt_dir_1]
 
-    def test_get_all_ckpts_with_pattern_that_matches_some(self, tmp_dir):
+    def test_get_all_ckpts_with_pattern_that_matches_some(self, tmpdir):
         """Test that we only return the checkpoints that match the pattern."""
-        ckpt_dir_0 = tmp_dir / "epoch_0"
+        tmpdir = Path(tmpdir)
+        ckpt_dir_0 = tmpdir / "epoch_0"
         ckpt_dir_0.mkdir(parents=True, exist_ok=True)
 
-        ckpt_dir_1 = tmp_dir / "step_1"
-        ckpt_dir_1.mkdir(parents=True, exist_ok=True)
+        ckpt_dir_1 = tmpdir / "step_1"
+        ckpt_dir_1.mkdir()
 
-        all_ckpts = get_all_checkpoints_in_dir(tmp_dir)
+        all_ckpts = get_all_checkpoints_in_dir(tmpdir)
         assert len(all_ckpts) == 1
         assert all_ckpts == [ckpt_dir_0]
 
-    def test_get_all_ckpts_override_pattern(self, tmp_dir):
+    def test_get_all_ckpts_override_pattern(self, tmpdir):
         """Test that we can override the default pattern and it works."""
-        ckpt_dir_0 = tmp_dir / "epoch_0"
+        tmpdir = Path(tmpdir)
+        ckpt_dir_0 = tmpdir / "epoch_0"
         ckpt_dir_0.mkdir(parents=True, exist_ok=True)
 
-        ckpt_dir_1 = tmp_dir / "step_1"
-        ckpt_dir_1.mkdir(parents=True, exist_ok=True)
+        ckpt_dir_1 = tmpdir / "step_1"
+        ckpt_dir_1.mkdir()
 
-        all_ckpts = get_all_checkpoints_in_dir(tmp_dir, pattern="step_*")
+        all_ckpts = get_all_checkpoints_in_dir(tmpdir, pattern="step_*")
         assert len(all_ckpts) == 1
         assert all_ckpts == [ckpt_dir_1]
 
-    def test_get_all_ckpts_only_return_dirs(self, tmp_dir):
+    def test_get_all_ckpts_only_return_dirs(self, tmpdir):
         """Test that even if a file matches the pattern, we only return directories."""
-        ckpt_dir_0 = tmp_dir / "epoch_0"
+        tmpdir = Path(tmpdir)
+        ckpt_dir_0 = tmpdir / "epoch_0"
         ckpt_dir_0.mkdir(parents=True, exist_ok=True)
 
-        file = tmp_dir / "epoch_1"
-        ckpt_dir_1.touch()
+        file = tmpdir / "epoch_1"
+        file.touch()
 
-        all_ckpts = get_all_checkpoints_in_dir(tmp_dir)
+        all_ckpts = get_all_checkpoints_in_dir(tmpdir)
         assert len(all_ckpts) == 1
         assert all_ckpts == [ckpt_dir_0]
 
-    def test_get_all_ckpts_non_unique(self, tmp_dir):
-        """Test that we return all checkpoints, even if they have the same name."""
-        ckpt_dir_0 = tmp_dir / "epoch_0"
-        ckpt_dir_0.mkdir(parents=True, exist_ok=True)
-
-        ckpt_dir_1 = tmp_dir / "epoch_0"
-        ckpt_dir_1.mkdir(parents=True, exist_ok=True)
-
-        all_ckpts = get_all_checkpoints_in_dir(tmp_dir)
-        assert len(all_ckpts) == 2
-        assert all_ckpts == [ckpt_dir_0, ckpt_dir_1]
-
 
 class TestPruneSurplusCheckpoints:
     """Series of tests for the ``prune_surplus_checkpoints`` function."""
 
-    def test_prune_surplus_checkpoints_simple(self, tmp_dir):
-        ckpt_dir_0 = tmp_dir / "epoch_0"
+    def test_prune_surplus_checkpoints_simple(self, tmpdir):
+        tmpdir = Path(tmpdir)
+        ckpt_dir_0 = tmpdir / "epoch_0"
         ckpt_dir_0.mkdir(parents=True, exist_ok=True)
 
-        ckpt_dir_1 = tmp_dir / "epoch_1"
-        ckpt_dir_1.mkdir(parents=True, exist_ok=True)
+        ckpt_dir_1 = tmpdir / "epoch_1"
+        ckpt_dir_1.mkdir()
 
-        prune_surplus_checkpoints(tmp_dir, 1)
-        remaining_ckpts = os.listdir(tmp_dir)
+        prune_surplus_checkpoints([ckpt_dir_0, ckpt_dir_1], 1)
+        remaining_ckpts = os.listdir(tmpdir)
         assert len(remaining_ckpts) == 1
         assert remaining_ckpts == ["epoch_1"]
 
-    def test_prune_surplus_checkpoints_keep_last_invalid(self, tmp_dir):
+    def test_prune_surplus_checkpoints_keep_last_invalid(self, tmpdir):
         """Test that we raise an error if keep_last_n_checkpoints is not >= 1"""
-        ckpt_dir_0 = tmp_dir / "epoch_0"
+        tmpdir = Path(tmpdir)
+        ckpt_dir_0 = tmpdir / "epoch_0"
         ckpt_dir_0.mkdir(parents=True, exist_ok=True)
 
-        ckpt_dir_1 = tmp_dir / "epoch_1"
-        ckpt_dir_1.mkdir(parents=True, exist_ok=True)
+        ckpt_dir_1 = tmpdir / "epoch_1"
+        ckpt_dir_1.mkdir()
 
-        with pytest.raises(ValueError, match="keep_last_n_checkpoints must be >= 1"):
-            prune_surplus_checkpoints(tmp_dir, 0)
+        with pytest.raises(
+            ValueError,
+            match="keep_last_n_checkpoints must be greater than or equal to 1",
+        ):
+            prune_surplus_checkpoints([ckpt_dir_0, ckpt_dir_1], 0)