Work around nanoarrow bug

Author: WillAyd

pandas/_libs/arrow_string_accumulations.cc

@@ -36,9 +36,25 @@ static auto CumSum(struct ArrowArrayStream *array_stream,
   bool seen_na = false;
   std::stringstream ss{};
 
+  // TODO: we can simplify this further if we just iterate on the array
+  // and not the array view, but there is an upstream bug in nanoarrow
+  // that prevents that
+  // https://github.com/apache/arrow-nanoarrow/issues/701
+  nanoarrow::UniqueArrayView array_view{};
+  nanoarrow::UniqueSchema schema{};
+  NANOARROW_THROW_NOT_OK(
+      ArrowArrayStreamGetSchema(array_stream, schema.get(), nullptr));
+
   nanoarrow::ViewArrayStream array_stream_view(array_stream);
   for (const auto &array : array_stream_view) {
-    for (const auto &sv : nanoarrow::ViewArrayAsBytes<OffsetSize>(&array)) {
+    array_view.reset();
+    NANOARROW_THROW_NOT_OK(
+        ArrowArrayViewInitFromSchema(array_view.get(), schema.get(), nullptr));
+    NANOARROW_THROW_NOT_OK(
+        ArrowArrayViewSetArray(array_view.get(), &array, nullptr));
+
+    for (const auto &sv :
+         nanoarrow::ViewArrayAsBytes<OffsetSize>(array_view.get())) {
       if ((!sv || seen_na) && !skipna) {
         seen_na = true;
         ArrowArrayAppendNull(out, 1);
@@ -68,9 +84,25 @@ static auto CumMinOrMax(struct ArrowArrayStream *array_stream,
   bool seen_na = false;
   std::optional<std::string> current_str{};
 
+  // TODO: we can simplify this further if we just iterate on the array
+  // and not the array view, but there is an upstream bug in nanoarrow
+  // that prevents that
+  // https://github.com/apache/arrow-nanoarrow/issues/701
+  nanoarrow::UniqueArrayView array_view{};
+  nanoarrow::UniqueSchema schema{};
+  NANOARROW_THROW_NOT_OK(
+      ArrowArrayStreamGetSchema(array_stream, schema.get(), nullptr));
+
   nanoarrow::ViewArrayStream array_stream_view(array_stream);
   for (const auto &array : array_stream_view) {
-    for (const auto &sv : nanoarrow::ViewArrayAsBytes<OffsetSize>(&array)) {
+    array_view.reset();
+    NANOARROW_THROW_NOT_OK(
+        ArrowArrayViewInitFromSchema(array_view.get(), schema.get(), nullptr));
+    NANOARROW_THROW_NOT_OK(
+        ArrowArrayViewSetArray(array_view.get(), &array, nullptr));
+
+    for (const auto &sv :
+         nanoarrow::ViewArrayAsBytes<OffsetSize>(array_view.get())) {
       if ((!sv || seen_na) && !skipna) {
         seen_na = true;
         ArrowArrayAppendNull(out, 1);