Adding upstream version 26.6.0.

Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>

tests/dialects/test_dune.py

@@ -0,0 +1,23 @@
+from tests.dialects.test_dialect import Validator
+
+
+class TestDune(Validator):
+    dialect = "dune"
+
+    def test_dune(self):
+        self.validate_identity("CAST(x AS INT256)")
+        self.validate_identity("CAST(x AS UINT256)")
+
+        self.validate_all(
+            "SELECT 0xdeadbeef",
+            read={
+                "dune": "SELECT X'deadbeef'",
+                "postgres": "SELECT x'deadbeef'",
+                "trino": "SELECT X'deadbeef'",
+            },
+            write={
+                "dune": "SELECT 0xdeadbeef",
+                "postgres": "SELECT x'deadbeef'",
+                "trino": "SELECT X'deadbeef'",
+            },
+        )