add specific tests for check_array_indexer

Author: jorisvandenbossche

pandas/tests/indexing/test_check_indexer.py

@@ -0,0 +1,87 @@
+import numpy as np
+import pytest
+
+import pandas as pd
+import pandas._testing as tm
+from pandas.api.indexers import check_array_indexer
+
+
+@pytest.mark.parametrize(
+    "indexer, expected",
+    [
+        # integer
+        ([1, 2], np.array([1, 2], dtype=np.intp)),
+        (np.array([1, 2], dtype="int64"), np.array([1, 2], dtype=np.intp)),
+        (pd.array([1, 2], dtype="Int32"), np.array([1, 2], dtype=np.intp)),
+        (pd.Index([1, 2]), np.array([1, 2], dtype=np.intp)),
+        # boolean
+        ([True, False, True], np.array([True, False, True], dtype=np.bool_)),
+        (np.array([True, False, True]), np.array([True, False, True], dtype=np.bool_)),
+        (
+            pd.array([True, False, True], dtype="boolean"),
+            np.array([True, False, True], dtype=np.bool_),
+        ),
+        # other
+        ([], np.array([], dtype=np.intp)),
+    ],
+)
+def test_valid_input(indexer, expected):
+    array = np.array([1, 2, 3])
+    result = check_array_indexer(array, indexer)
+    tm.assert_numpy_array_equal(result, expected)
+
+
+@pytest.mark.parametrize(
+    "indexer", [[True, False, None], pd.array([True, False, None], dtype="boolean")],
+)
+def test_bool_raise_missing_values(indexer):
+    array = np.array([1, 2, 3])
+
+    msg = "Cannot mask with a boolean indexer containing NA values"
+    with pytest.raises(ValueError, match=msg):
+        check_array_indexer(array, indexer)
+
+
+@pytest.mark.parametrize(
+    "indexer",
+    [
+        [True, False],
+        pd.array([True, False], dtype="boolean"),
+        np.array([True, False], dtype=np.bool_),
+    ],
+)
+def test_bool_raise_length(indexer):
+    array = np.array([1, 2, 3])
+
+    msg = "Boolean index has wrong length"
+    with pytest.raises(IndexError, match=msg):
+        check_array_indexer(array, indexer)
+
+
+@pytest.mark.parametrize(
+    "indexer", [[0, 1, None], pd.array([0, 1, pd.NA], dtype="Int64")],
+)
+def test_int_raise_missing_values(indexer):
+    array = np.array([1, 2, 3])
+
+    msg = "Cannot index with an integer indexer containing NA values"
+    with pytest.raises(ValueError, match=msg):
+        check_array_indexer(array, indexer)
+
+
+@pytest.mark.parametrize(
+    "indexer",
+    [
+        [0.0, 1.0],
+        np.array([1.0, 2.0], dtype="float64"),
+        np.array([True, False], dtype=object),
+        pd.Index([True, False], dtype=object),
+        pd.array(["a", "b"], dtype="string"),
+    ],
+)
+def test_raise_invalid_array_dtypes(indexer):
+    array = np.array([1, 2, 3])
+
+    msg = "arrays used as indices must be of integer or boolean type"
+    with pytest.raises(IndexError, match=msg):
+        check_array_indexer(array, indexer)