Adding upstream version 18.2.0.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tests/dataframe/unit/dataframe_test_base.py

@@ -0,0 +1,23 @@
+import typing as t
+import unittest
+
+import sqlglot
+from sqlglot import MappingSchema
+from sqlglot.dataframe.sql import SparkSession
+from sqlglot.dataframe.sql.dataframe import DataFrame
+from sqlglot.helper import ensure_list
+
+
+class DataFrameTestBase(unittest.TestCase):
+    def setUp(self) -> None:
+        sqlglot.schema = MappingSchema()
+        SparkSession._instance = None
+
+    def compare_sql(
+        self, df: DataFrame, expected_statements: t.Union[str, t.List[str]], pretty=False
+    ):
+        actual_sqls = df.sql(pretty=pretty)
+        expected_statements = ensure_list(expected_statements)
+        self.assertEqual(len(expected_statements), len(actual_sqls))
+        for expected, actual in zip(expected_statements, actual_sqls):
+            self.assertEqual(expected, actual)