Fix: normalize column names in column_descriptions dict (#2731)

Author: treysp

sqlmesh/core/model/meta.py

@@ -219,6 +219,8 @@ def _columns_validator(
     def _column_descriptions_validator(
         cls, vs: t.Any, values: t.Dict[str, t.Any]
     ) -> t.Optional[t.Dict[str, str]]:
+        dialect = values.get("dialect")
+
         if vs is None:
             return None
 
@@ -228,10 +230,15 @@ def _column_descriptions_validator(
         if isinstance(vs, (exp.Tuple, exp.Array)):
             vs = vs.expressions
 
-        col_descriptions = (
+        raw_col_descriptions = (
             vs if isinstance(vs, dict) else {v.this.name: v.expression.name for v in vs}
         )
 
+        col_descriptions = {
+            normalize_identifiers(k, dialect=dialect).name: v
+            for k, v in raw_col_descriptions.items()
+        }
+
         columns_to_types = values.get("columns_to_types_")
         if columns_to_types:
             for column_name in col_descriptions:

tests/core/test_model.py

@@ -1752,6 +1752,35 @@ def my_model(context):
         assert not mock_logger.call_args
 
 
+def test_python_model_decorator_col_descriptions() -> None:
+    # `columns` and `column_descriptions` column names are different cases, but name normalization makes both lower
+    @model("col_descriptions", columns={"col": "int"}, column_descriptions={"COL": "a column"})
+    def a_model(context):
+        pass
+
+    py_model = model.get_registry()["col_descriptions"].model(
+        module_path=Path("."),
+        path=Path("."),
+    )
+
+    assert py_model.columns_to_types.keys() == py_model.column_descriptions.keys()
+
+    # error: `columns` and `column_descriptions` column names are different cases, quoting preserves case
+    @model(
+        "col_descriptions_quoted",
+        columns={'"col"': "int"},
+        column_descriptions={'"COL"': "a column"},
+    )
+    def b_model(context):
+        pass
+
+    with pytest.raises(ConfigError, match="a description is provided for column 'COL'"):
+        py_model = model.get_registry()["col_descriptions_quoted"].model(
+            module_path=Path("."),
+            path=Path("."),
+        )
+
+
 def test_star_expansion(assert_exp_eq) -> None:
     context = Context(config=Config())