ENH: searchsorted: add input validation for parameter 'side'

Author: mdhaber

src/array_api_extra/_delegation.py

@@ -691,6 +691,10 @@ def searchsorted(
     if xp is None:
         xp = array_namespace(x1, x2)
 
+    if side not in {"left", "right"}:
+        message = "`side` must be either 'left' or 'right'."
+        raise ValueError(message)
+
     xp_default_int = _funcs.default_dtype(xp, kind="integral")
     y_0d = xp.asarray(x2).ndim == 0
     x_1d = x1.ndim <= 1

tests/test_funcs.py

@@ -1769,6 +1769,11 @@ def xp_searchsorted(
 @pytest.mark.skip_xp_backend(Backend.DASK, reason="no take_along_axis")
 @pytest.mark.skip_xp_backend(Backend.SPARSE, reason="no searchsorted")
 class TestSearchsorted:
+    def test_input_validation(self, xp: ModuleType):
+        message = "`side` must be either 'left' or 'right'."
+        with pytest.raises(ValueError, match=message):
+            _ = searchsorted(xp.asarray([1, 2]), xp.asarray([1, 2]), side="center")  # type: ignore[arg-type]  # pyright: ignore[reportArgumentType]
+
     @pytest.mark.parametrize("side", ["left", "right"])
     @pytest.mark.parametrize("ties", [False, True])
     @pytest.mark.parametrize(