From dfed8c3be0612a199c1a554422ea818f2fa50586 Mon Sep 17 00:00:00 2001
From: "s.kyon" <251157463+skyon0522-ai@users.noreply.github.com>
Date: Fri, 9 Oct 2026 00:26:40 +0900
Subject: [PATCH] GH-45880: [C++][Python] Return TypeError for map parent
 indices

---
 cpp/src/arrow/compute/kernels/vector_nested.cc      |  2 ++
 cpp/src/arrow/compute/kernels/vector_nested_test.cc | 12 ++++++++++++
 python/pyarrow/tests/test_array.py                  | 11 +++++++++++
 3 files changed, 25 insertions(+)

diff --git a/cpp/src/arrow/compute/kernels/vector_nested.cc b/cpp/src/arrow/compute/kernels/vector_nested.cc
index d515e60fbee2..e0d881c2a5a8 100644
--- a/cpp/src/arrow/compute/kernels/vector_nested.cc
+++ b/cpp/src/arrow/compute/kernels/vector_nested.cc
@@ -167,6 +167,8 @@ struct ListParentIndicesArray {
                              type.ToString());
   }
 
+  Status Visit(const MapType& type) { return Visit(static_cast<const DataType&>(type)); }
+
   static Result<std::shared_ptr<ArrayData>> Exec(KernelContext* ctx,
                                                  const std::shared_ptr<ArrayData>& input,
                                                  int64_t base_output_offset = 0) {
diff --git a/cpp/src/arrow/compute/kernels/vector_nested_test.cc b/cpp/src/arrow/compute/kernels/vector_nested_test.cc
index 07f9c44db52a..afafe1469859 100644
--- a/cpp/src/arrow/compute/kernels/vector_nested_test.cc
+++ b/cpp/src/arrow/compute/kernels/vector_nested_test.cc
@@ -271,6 +271,18 @@ TEST(TestVectorNested, ListParentIndices) {
   }
 }
 
+TEST(TestVectorNested, ListParentIndicesMap) {
+  auto input =
+      ArrayFromJSON(map(utf8(), uint16()), R"([[["a", 1], ["b", 2]], [["c", 3]]])");
+  auto chunked =
+      std::make_shared<ChunkedArray>(ArrayVector{input->Slice(0, 1), input->Slice(1)});
+  for (const auto& datum : {Datum(input), Datum(chunked)}) {
+    EXPECT_RAISES_WITH_MESSAGE_THAT(TypeError,
+                                    ::testing::HasSubstr("expects list input, got map"),
+                                    CallFunction("list_parent_indices", {datum}));
+  }
+}
+
 TEST(TestVectorNested, ListParentIndicesChunkedArray) {
   const auto types = {
       list(int16()),
diff --git a/python/pyarrow/tests/test_array.py b/python/pyarrow/tests/test_array.py
index 74ff837e16e8..0e6e16a40f92 100644
--- a/python/pyarrow/tests/test_array.py
+++ b/python/pyarrow/tests/test_array.py
@@ -3369,6 +3369,17 @@ def test_list_value_parent_indices(list_type):
     assert arr.value_parent_indices().equals(expected)
 
 
+def test_map_value_parent_indices():
+    arr = pa.array([{'a': 1, 'b': 2}, {'c': 3}],
+                   type=pa.map_(pa.utf8(), pa.uint16()))
+
+    message = "expects list input, got map"
+    with pytest.raises(pa.ArrowTypeError, match=message):
+        arr.value_parent_indices()
+    with pytest.raises(pa.ArrowTypeError, match=message):
+        pc.list_parent_indices(arr)
+
+
 @pytest.mark.parametrize(('offset_type', 'list_type'),
                          [(pa.int32(), pa.list_(pa.int32())),
                           (pa.int32(), pa.list_(pa.int32(), list_size=2)),