cover all cases

Author: lucascolley

src/array_api_extra/_lib/_utils.py

@@ -42,6 +42,7 @@ def in1d(
                 mask |= x1 == a
         return mask
 
+    rev_idx = xp.empty(0)  # placeholder
     if not assume_unique:
         x1, rev_idx = xp.unique_inverse(x1)
         x2 = xp.unique_values(x2)
@@ -61,7 +62,4 @@ def in1d(
 
     if assume_unique:
         return ret[: x1.shape[0]]
-    # https://github.com/KotlinIsland/basedmypy/issues/826
-    # https://github.com/pylint-dev/pylint/issues/10095
-    # pylint: disable=possibly-used-before-assignment
-    return xp.take(ret, rev_idx, axis=0)  # type: ignore[possibly-undefined]  # pyright: ignore[reportPossiblyUnboundVariable]
+    return xp.take(ret, rev_idx, axis=0)

tests/test_utils.py

@@ -1,17 +1,24 @@
 from __future__ import annotations  # https://github.com/pylint-dev/pylint/pull/9990
 
+import typing
+
 # data-apis/array-api-strict#6
 import array_api_strict as xp  # type: ignore[import-untyped]  # pyright: ignore[reportMissingTypeStubs]
+import pytest
 from numpy.testing import assert_array_equal
 
 from array_api_extra._lib._utils import in1d
 
+if typing.TYPE_CHECKING:
+    from array_api_extra._lib._typing import Array
+
 
 # some test coverage already provided by TestSetDiff1D
 class TestIn1D:
-    def test_no_invert_assume_unique(self):
+    # cover both code paths
+    @pytest.mark.parametrize("x2", [xp.arange(9), xp.arange(15)])
+    def test_no_invert_assume_unique(self, x2: Array):
         x1 = xp.asarray([3, 8, 20])
-        x2 = xp.arange(15)
         expected = xp.asarray([True, True, False])
         actual = in1d(x1, x2, xp=xp)
         assert_array_equal(actual, expected)