SNOW-1887104: Update OBJECT semantics

src/snowflake/snowpark/_internal/type_utils.py

@@ -198,6 +198,8 @@ def convert_sf_to_sp_type(
         return ArrayType(semi_structured_fill)
     if column_type_name == "VARIANT":
         return VariantType()
+    if context._should_use_structured_type_semantics() and column_type_name == "OBJECT":
+        return StructType()
     if column_type_name in {"OBJECT", "MAP"}:
         return MapType(semi_structured_fill, semi_structured_fill)
     if column_type_name == "GEOGRAPHY":
@@ -678,6 +680,10 @@ def python_type_to_snow_type(
             if tp_args
             else None
         )
+        if (
+            key_type is None or value_type is None
+        ) and context._should_use_structured_type_semantics():
+            return StructType(), False
         return MapType(key_type, value_type), False
 
     if installed_pandas:

src/snowflake/snowpark/_internal/udf_utils.py

@@ -1261,7 +1261,11 @@ def create_python_udf_or_sp(
 
     if replace and if_not_exists:
         raise ValueError("options replace and if_not_exists are incompatible")
-    if isinstance(return_type, StructType) and not return_type.structured:
+    if (
+        isinstance(return_type, StructType)
+        and not return_type.structured
+        and object_type != TempObjectType.AGGREGATE_FUNCTION
+    ):
         return_sql = f'RETURNS TABLE ({",".join(f"{field.name} {convert_sp_to_sf_type(field.datatype)}" for field in return_type.fields)})'
     elif installed_pandas and isinstance(return_type, PandasDataFrameType):
         return_sql = f'RETURNS TABLE ({",".join(f"{name} {convert_sp_to_sf_type(datatype)}" for name, datatype in zip(return_type.col_names, return_type.col_types))})'

src/snowflake/snowpark/types.py

@@ -403,15 +403,9 @@ def __init__(
         value_contains_null: bool = True,
     ) -> None:
         if context._should_use_structured_type_semantics():
-            if (key_type is None and value_type is not None) or (
-                key_type is not None and value_type is None
-            ):
-                raise ValueError(
-                    "Must either set both key_type and value_type or leave both unset."
-                )
-            self.structured = (
-                structured if structured is not None else key_type is not None
-            )
+            if key_type is None or value_type is None:
+                raise ValueError("MapType requires key and value type be set.")
+            self.structured = True
             self.key_type = key_type
             self.value_type = value_type
         else:
@@ -476,10 +470,6 @@ def valueType(self):
 
     def _fill_ast(self, ast: proto.SpDataType) -> None:
         ast.sp_map_type.structured = self.structured
-        if self.key_type is None or self.value_type is None:
-            raise NotImplementedError(
-                "SNOW-1862700: AST does not support empty key or value type."
-            )
         self.key_type._fill_ast(ast.sp_map_type.key_ty)
         self.value_type._fill_ast(ast.sp_map_type.value_ty)
 

src/snowflake/snowpark/udaf.py

@@ -40,7 +40,7 @@
     warning,
 )
 from snowflake.snowpark.column import Column
-from snowflake.snowpark.types import DataType, MapType
+from snowflake.snowpark.types import DataType, MapType, StructType
 
 # Python 3.8 needs to use typing.Iterable because collections.abc.Iterable is not subscriptable
 # Python 3.9 can use both
@@ -717,7 +717,7 @@ def _do_register_udaf(
                     "_do_register_udaf",
                     "Snowflake does not support structured maps as return type for UDAFs. Downcasting to semi-structured object.",
                 )
-                return_type = MapType()
+                return_type = StructType()
 
         # Capture original parameters.
         if _emit_ast:

tests/integ/scala/test_datatype_suite.py

@@ -6,7 +6,6 @@
 
 # Many of the tests have been moved to unit/scala/test_datattype_suite.py
 from decimal import Decimal
-from unittest import mock
 
 import logging
 import pytest
@@ -533,18 +532,10 @@ def test_structured_dtypes_negative(structured_type_session, structured_type_sup
     if not structured_type_support:
         pytest.skip("Test requires structured type support.")
 
-    # SNOW-1862700: Map Type missing element or value fails to generate AST.
-    with pytest.raises(
-        NotImplementedError, match="AST does not support empty key or value type."
-    ):
-        x = MapType()
-        x._fill_ast(mock.Mock())
+    with pytest.raises(ValueError, match="MapType requires key and value type be set."):
+        MapType()
 
-    # Maptype requires both key and value type be set if either is set
-    with pytest.raises(
-        ValueError,
-        match="Must either set both key_type and value_type or leave both unset.",
-    ):
+    with pytest.raises(ValueError, match="MapType requires key and value type be set."):
         MapType(StringType())
 
 
@@ -586,7 +577,7 @@ def finish(self) -> dict:
             "Snowflake does not support structured maps as return type for UDAFs. Downcasting to semi-structured object."
             in caplog.text
         )
-        assert MapCollector._return_type == MapType()
+        assert MapCollector._return_type == StructType()
 
 
 @pytest.mark.skipif(
@@ -978,8 +969,8 @@ def test_structured_dtypes_cast(structured_type_session, structured_type_support
     expected_semi_schema = StructType(
         [
             StructField("ARR", ArrayType(), nullable=True),
-            StructField("MAP", MapType(), nullable=True),
-            StructField("OBJ", MapType(), nullable=True),
+            StructField("MAP", StructType(), nullable=True),
+            StructField("OBJ", StructType(), nullable=True),
         ]
     )
     expected_structured_schema = StructType(
@@ -1008,8 +999,8 @@ def test_structured_dtypes_cast(structured_type_session, structured_type_support
         schema=StructType(
             [
                 StructField("arr", ArrayType()),
-                StructField("map", MapType()),
-                StructField("obj", MapType()),
+                StructField("map", StructType()),
+                StructField("obj", StructType()),
             ]
         ),
     )