add test for downcast schema

Author: kevinjqliu

tests/table/test_init.py

@@ -1091,6 +1091,20 @@ def test_schema_mismatch_additional_field(table_schema_simple: Schema) -> None:
         _check_schema_compatible(table_schema_simple, other_schema)
 
 
+def test_schema_downcast(table_schema_simple: Schema) -> None:
+    # large_string type is compatible with string type
+    other_schema = pa.schema((
+        pa.field("foo", pa.large_string(), nullable=True),
+        pa.field("bar", pa.int32(), nullable=False),
+        pa.field("baz", pa.bool_(), nullable=True),
+    ))
+
+    try:
+        _check_schema_compatible(table_schema_simple, other_schema)
+    except Exception:
+        pytest.fail("Unexpected Exception raised when calling `_check_schema`")
+
+
 def test_table_properties(example_table_metadata_v2: Dict[str, Any]) -> None:
     # metadata properties are all strings
     for k, v in example_table_metadata_v2["properties"].items():