Spell out expected pairs in test

tests/test_unit/test_kinematics.py

@@ -1,5 +1,3 @@
-import itertools
-
 import numpy as np
 import pytest
 import xarray as xr
@@ -313,54 +311,44 @@ def test_cdist_with_single_dim_inputs(valid_dataset, selection_fn, request):
         assert isinstance(kinematics._cdist(a, b, "individuals"), xr.DataArray)
 
 
-def expected_pairwise_distances(pairs, input_ds, dim):
-    """Return a list of the expected data variable names
-    for pairwise distances tests.
-    """
-    if pairs == "all":
-        paired_elements = list(
-            itertools.combinations(getattr(input_ds, dim).values, 2)
-        )
-    else:
-        paired_elements = [
-            (elem1, elem2)
-            for elem1, elem2_list in pairs.items()
-            for elem2 in (
-                [elem2_list] if isinstance(elem2_list, str) else elem2_list
-            )
-        ]
-    expected_data = [
-        f"dist_{elem1}_{elem2}" for elem1, elem2 in paired_elements
-    ]
-    return expected_data
-
-
 @pytest.mark.parametrize(
-    "dim, pairs",
+    "dim, pairs, expected_data_vars",
     [
-        ("individuals", {"id_1": ["id_2"]}),  # list input
-        ("individuals", {"id_1": "id_2"}),  # string input
-        ("individuals", {"id_1": ["id_2"], "id_2": "id_1"}),
-        ("individuals", "all"),  # all pairs
-        ("keypoints", {"centroid": ["left"]}),  # list input
-        ("keypoints", {"centroid": "left"}),  # string input
-        ("keypoints", {"centroid": ["left"], "left": "right"}),
-        ("keypoints", "all"),  # all pairs
+        ("individuals", {"id_1": ["id_2"]}, None),  # list input
+        ("individuals", {"id_1": "id_2"}, None),  # string input
+        (
+            "individuals",
+            {"id_1": ["id_2"], "id_2": "id_1"},
+            [("id_1", "id_2"), ("id_2", "id_1")],
+        ),
+        ("individuals", "all", None),  # all pairs
+        ("keypoints", {"centroid": ["left"]}, None),  # list input
+        ("keypoints", {"centroid": "left"}, None),  # string input
+        (
+            "keypoints",
+            {"centroid": ["left"], "left": "right"},
+            [("centroid", "left"), ("left", "right")],
+        ),
+        (
+            "keypoints",
+            "all",
+            [("centroid", "left"), ("centroid", "right"), ("left", "right")],
+        ),  # all pairs
     ],
 )
 def test_compute_pairwise_distances_with_valid_pairs(
-    valid_poses_dataset_uniform_linear_motion, dim, pairs
+    valid_poses_dataset_uniform_linear_motion, dim, pairs, expected_data_vars
 ):
     """Test that the expected pairwise distances are computed
     for valid ``pairs`` inputs.
     """
     result = kinematics.compute_pairwise_distances(
         valid_poses_dataset_uniform_linear_motion.position, dim, pairs
     )
-    expected_data_vars = expected_pairwise_distances(
-        pairs, valid_poses_dataset_uniform_linear_motion, dim
-    )
     if isinstance(result, dict):
+        expected_data_vars = [
+            f"dist_{pair[0]}_{pair[1]}" for pair in expected_data_vars
+        ]
         assert set(result.keys()) == set(expected_data_vars)
     else:  # expect single DataArray
         assert isinstance(result, xr.DataArray)