test: add xfail test for duckdb map NULL bug

ibis/backends/tests/test_map.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import duckdb
 import numpy as np
 import pandas as pd
 import pandas.testing as tm
@@ -11,6 +12,7 @@
 import ibis.common.exceptions as exc
 import ibis.expr.datatypes as dt
 from ibis.backends.tests.errors import PsycoPg2InternalError, Py4JJavaError
+from ibis.expr import operations as ops
 
 pytestmark = [
     pytest.mark.never(
@@ -42,6 +44,16 @@ def test_map_nulls(con, kv):
     assert con.execute(m) is None
 
 
+@pytest.mark.xfail(
+    raises=duckdb.BinderException,
+    reason="https://github.com/ibis-project/ibis/issues/8632",
+)
+def test_map_null_workaround_xfail():
+    null = ibis.literal(None, type="array<int64>")
+    m = ops.Map(null, [1, 2]).to_expr()
+    assert ibis.duckdb.connect().execute(m) is None
+
+
 @pytest.mark.notimpl(["pandas", "dask"])
 def test_map_table(backend):
     table = backend.map