Skip to content
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
9 changes: 6 additions & 3 deletions pyiceberg/io/pyarrow.py
Original file line number Diff line number Diff line change
Expand Up @@ -2073,9 +2073,12 @@ def list(self, list_type: ListType, list_array: pa.Array | None, value_array: pa
if isinstance(list_array, (pa.ListArray, pa.LargeListArray, pa.FixedSizeListArray)) and value_array is not None:
list_initializer = pa.large_list if isinstance(list_array, pa.LargeListArray) else pa.list_
if isinstance(value_array, pa.StructArray):
# This can be removed once this has been fixed:
# https://github.com/apache/arrow/issues/38809
list_array = pa.LargeListArray.from_arrays(list_array.offsets, value_array)
# Rebuilding is what applies the projection to the element struct. A plain
# cast would not do: Iceberg renames by field-id, while cast matches the
# element fields by name and would silently null out any renamed one. The
# mask has to be carried over because the offsets buffer alone cannot
# express a null list, only an empty one.
list_array = pa.LargeListArray.from_arrays(list_array.offsets, value_array, mask=list_array.is_null())
value_array = self._cast_if_needed(list_type.element_field, value_array)
arrow_field = list_initializer(self._construct_field(list_type.element_field, value_array.type))
return list_array.cast(arrow_field)
Expand Down
5 changes: 1 addition & 4 deletions tests/integration/test_reads.py
Original file line number Diff line number Diff line change
Expand Up @@ -994,10 +994,7 @@ def test_null_list_and_map(catalog: Catalog) -> None:
arrow_table = table_test_empty_list_and_map.scan().to_arrow()
assert arrow_table["col_list"].to_pylist() == [None, []]
assert arrow_table["col_map"].to_pylist() == [None, []]
# This should be:
# assert arrow_table["col_list_with_struct"].to_pylist() == [None, [{'test': 1}]]
# Once https://github.com/apache/arrow/issues/38809 has been fixed
assert arrow_table["col_list_with_struct"].to_pylist() == [[], [{"test": 1}]]
assert arrow_table["col_list_with_struct"].to_pylist() == [None, [{"test": 1}]]


@pytest.mark.integration
Expand Down
71 changes: 71 additions & 0 deletions tests/io/test_pyarrow.py
Original file line number Diff line number Diff line change
Expand Up @@ -3210,6 +3210,77 @@ def test__to_requested_schema_float_promotion(
assert result.column(0).to_pylist() == [1.5, 2.25, 3.0, None]


def test__to_requested_schema_null_list_of_structs() -> None:
"""Test that a null list survives the write path when its element is a struct."""
requested_schema = Schema(
NestedField(
1,
"col_list_with_struct",
ListType(11, StructType(NestedField(111, "test", IntegerType(), required=False)), element_required=False),
required=False,
),
NestedField(2, "col_list", ListType(21, IntegerType(), element_required=False), required=False),
)
file_schema = requested_schema

arrow_schema = pa.schema(
[
pa.field("col_list_with_struct", pa.list_(pa.struct([pa.field("test", pa.int32())]))),
pa.field("col_list", pa.list_(pa.int32())),
]
)
batch = pa.RecordBatch.from_arrays(
[
pa.array([[{"test": 1}], [], None], type=arrow_schema.field(0).type),
pa.array([[1], [], None], type=arrow_schema.field(1).type),
],
schema=arrow_schema,
)

result = _to_requested_schema(
requested_schema, file_schema, batch, downcast_ns_timestamp_to_us=False, include_field_ids=False
)

# A null list and an empty list are different values, and only the struct-element
# case ever collapsed the former into the latter.
assert result.column(0).to_pylist() == [[{"test": 1}], [], None]
assert result.column(1).to_pylist() == [[1], [], None]


def test__to_requested_schema_renamed_field_in_list_of_structs() -> None:
"""Test that a field renamed inside a list element keeps its values."""
file_schema = Schema(
NestedField(
1,
"col",
ListType(11, StructType(NestedField(111, "before", IntegerType(), required=False)), element_required=False),
required=False,
),
)
requested_schema = Schema(
NestedField(
1,
"col",
ListType(11, StructType(NestedField(111, "after", IntegerType(), required=False)), element_required=False),
required=False,
),
)

arrow_schema = pa.schema([pa.field("col", pa.list_(pa.struct([pa.field("before", pa.int32())])))])
batch = pa.RecordBatch.from_arrays(
[pa.array([[{"before": 1}], [], None, [{"before": 3}]], type=arrow_schema.field(0).type)],
schema=arrow_schema,
)

result = _to_requested_schema(
requested_schema, file_schema, batch, downcast_ns_timestamp_to_us=False, include_field_ids=False
)

# Rebuilding the list from the projected element array is what carries the rename.
# Casting instead would match the element fields by name and yield nulls throughout.
assert result.column(0).to_pylist() == [[{"after": 1}], [], None, [{"after": 3}]]


def test_pyarrow_file_io_fs_by_scheme_cache() -> None:
# It's better to set up multi-region minio servers for an integration test once `endpoint_url` argument
# becomes available for `resolve_s3_region`
Expand Down