SNOW-1569916: fix local testing default timestamp timezone issue

CHANGELOG.md

@@ -17,6 +17,7 @@
 #### Bug Fixes
 
 - Fixed a bug where the truncate mode in `DataFrameWriter.save_as_table` incorrectly handled DataFrames containing only a subset of columns from the existing table.
+- Fixed a bug where function `to_timestamp` does not set the default timezone of the column datatype.
 
 ### Snowpark pandas API Updates
 
@@ -81,6 +82,7 @@
 
 - Fixed a bug where Window Functions LEAD and LAG do not handle option `ignore_nulls` properly.
 - Fixed a bug where values were not populated into the result DataFrame during the insertion of table merge operation.
+- Fixed a bug where the truncate mode in `DataFrameWriter.save_as_table` incorrectly handled DataFrames containing only a subset of columns from the existing table.
 
 #### Improvements
 

src/snowflake/snowpark/mock/_functions.py

@@ -22,6 +22,8 @@
 from snowflake.snowpark._internal.analyzer.expression import FunctionExpression
 from snowflake.snowpark.mock._options import numpy, pandas
 from snowflake.snowpark.mock._snowflake_data_type import (
+    _TIMESTAMP_TYPE_MAPPING,
+    _TIMESTAMP_TYPE_TIMEZONE_MAPPING,
     ColumnEmulator,
     ColumnType,
     TableEmulator,
@@ -943,7 +945,11 @@ def mock_to_timestamp(
     try_cast: bool = False,
 ):
     result = mock_to_timestamp_ntz(column, fmt, try_cast)
-    result.sf_type = ColumnType(TimestampType(), column.sf_type.nullable)
+
+    result.sf_type = ColumnType(
+        TimestampType(_TIMESTAMP_TYPE_TIMEZONE_MAPPING[_TIMESTAMP_TYPE_MAPPING]),
+        column.sf_type.nullable,
+    )
     return result
 
 

src/snowflake/snowpark/mock/_snowflake_data_type.py

@@ -19,6 +19,7 @@
     MapType,
     NullType,
     StringType,
+    TimestampTimeZone,
     TimestampType,
     TimeType,
     VariantType,
@@ -32,6 +33,17 @@
 PandasDataframeType = object if not installed_pandas else pd.DataFrame
 PandasSeriesType = object if not installed_pandas else pd.Series
 
+# https://docs.snowflake.com/en/sql-reference/parameters#label-timestamp-type-mapping
+# SNOW-1630258 for local testing session parameters support
+_TIMESTAMP_TYPE_MAPPING = "TIMESTAMP_NTZ"
+
+
+_TIMESTAMP_TYPE_TIMEZONE_MAPPING = {
+    "TIMESTAMP_NTZ": TimestampTimeZone.NTZ,
+    "TIMESTAMP_LTZ": TimestampTimeZone.LTZ,
+    "TIMESTAMP_TZ": TimestampTimeZone.TZ,
+}
+
 
 class Operator:
     def op(self, *operands):
@@ -302,6 +314,13 @@ def coerce_t1_into_t2(t1: DataType, t2: DataType) -> Optional[DataType]:
     elif isinstance(t1, (TimeType, TimestampType, MapType, ArrayType)):
         if isinstance(t2, VariantType):
             return t2
+        if isinstance(t1, TimestampType) and isinstance(t2, TimestampType):
+            if (
+                t1.tz is TimestampTimeZone.DEFAULT
+                and t2.tz is TimestampTimeZone.NTZ
+                and _TIMESTAMP_TYPE_MAPPING == "TIMESTAMP_NTZ"
+            ):
+                return t2
     return None
 
 

tests/integ/scala/test_dataframe_suite.py

@@ -1654,7 +1654,7 @@ def test_flatten_in_session(session):
     )
 
 
-def test_createDataFrame_with_given_schema(session, local_testing_mode):
+def test_createDataFrame_with_given_schema(session):
     schema = StructType(
         [
             StructField("string", StringType(84)),
@@ -1728,12 +1728,7 @@ def test_createDataFrame_with_given_schema(session, local_testing_mode):
             StructField("number", DecimalType(10, 3)),
             StructField("boolean", BooleanType()),
             StructField("binary", BinaryType()),
-            StructField(
-                "timestamp",
-                TimestampType(TimestampTimeZone.NTZ)
-                if not local_testing_mode
-                else TimestampType(),
-            ),  # depends on TIMESTAMP_TYPE_MAPPING
+            StructField("timestamp", TimestampType(TimestampTimeZone.NTZ)),
             StructField("timestamp_ntz", TimestampType(TimestampTimeZone.NTZ)),
             StructField("timestamp_ltz", TimestampType(TimestampTimeZone.LTZ)),
             StructField("timestamp_tz", TimestampType(TimestampTimeZone.TZ)),
@@ -1759,7 +1754,7 @@ def test_createDataFrame_with_given_schema_time(session):
     assert df.collect() == data
 
 
-def test_createDataFrame_with_given_schema_timestamp(session, local_testing_mode):
+def test_createDataFrame_with_given_schema_timestamp(session):
     schema = StructType(
         [
             StructField("timestamp", TimestampType()),
@@ -1780,7 +1775,7 @@ def test_createDataFrame_with_given_schema_timestamp(session, local_testing_mode
 
     assert (
         schema_str
-        == f"StructType([StructField('TIMESTAMP', TimestampType({'' if local_testing_mode else 'tz=ntz'}), nullable=True), "
+        == "StructType([StructField('TIMESTAMP', TimestampType(tz=ntz), nullable=True), "
         "StructField('TIMESTAMP_NTZ', TimestampType(tz=ntz), nullable=True), "
         "StructField('TIMESTAMP_LTZ', TimestampType(tz=ltz), nullable=True), "
         "StructField('TIMESTAMP_TZ', TimestampType(tz=tz), nullable=True)])"

tests/integ/scala/test_function_suite.py

@@ -3839,6 +3839,35 @@ def test_convert_timezone(session, local_testing_mode):
             ],
         )
 
+        df = TestData.datetime_primitives1(session).select("timestamp", "timestamp_ntz")
+
+        Utils.check_answer(
+            df.select(
+                *[
+                    convert_timezone(lit("UTC"), col, lit("Asia/Shanghai"))
+                    for col in df.columns
+                ]
+            ),
+            [
+                Row(
+                    datetime(2024, 2, 1, 4, 0),
+                    datetime(2017, 2, 24, 4, 0, 0, 456000),
+                )
+            ],
+        )
+
+        df = TestData.datetime_primitives1(session).select(
+            "timestamp_ltz", "timestamp_tz"
+        )
+        with pytest.raises(SnowparkSQLException):
+            # convert_timezone function does not accept non-TimestampTimeZone.NTZ datetime
+            df.select(
+                *[
+                    convert_timezone(lit("UTC"), col, lit("Asia/Shanghai"))
+                    for col in df.columns
+                ]
+            ).collect()
+
         LocalTimezone.set_local_timezone()