Fix: parse python model column types with dialect (#3633)

Author: treysp

sqlmesh/core/model/decorator.py

@@ -71,7 +71,9 @@ def __init__(self, name: t.Optional[str] = None, is_sql: bool = False, **kwargs:
             column_name: (
                 column_type
                 if isinstance(column_type, exp.DataType)
-                else exp.DataType.build(str(column_type))
+                else exp.DataType.build(
+                    str(column_type), dialect=self.kwargs.get("dialect", self._dialect)
+                )
             )
             for column_name, column_type in self.kwargs.pop("columns", {}).items()
         }

tests/core/test_model.py

@@ -10,6 +10,7 @@
 import pytest
 from pytest_mock.plugin import MockerFixture
 from sqlglot import exp, parse_one
+from sqlglot.errors import ParseError
 from sqlglot.schema import MappingSchema
 from sqlmesh.cli.example_project import init_example_project
 
@@ -5310,6 +5311,27 @@ def test(context, **kwargs):
     assert m.time_column.column.sql() == '"Y"'
     assert m.time_column.format == "%Y-%m-%d"
 
+    # column type parseable by default dialect: no error
+    model._dialect = "clickhouse"
+
+    @model("good", columns={'"COL"': "DateTime64(9)"})
+    def a_model(context):
+        pass
+
+    # column type not parseable by default dialect and no explicit dialect: error
+    model._dialect = "snowflake"
+
+    with pytest.raises(ParseError, match="No expression was parsed from 'DateTime64\(9\)'"):
+
+        @model("bad", columns={'"COL"': "DateTime64(9)"})
+        def a_model(context):
+            pass
+
+    # column type not parseable by default dialect and explicit dialect specified: no error
+    @model("good", columns={'"COL"': "DateTime64(9)"}, dialect="clickhouse")
+    def a_model(context):
+        pass
+
     model._dialect = None