checkpoint-postgres: handle null chars in metadata (#1885)

libs/checkpoint-postgres/tests/test_sync.py

@@ -101,3 +101,12 @@ class TestPostgresSaver:
             } == {"", "inner"}
 
             # TODO: test before and limit params
+
+    def test_null_chars(self) -> None:
+        with PostgresSaver.from_conn_string(DEFAULT_URI) as saver:
+            config = saver.put(self.config_1, self.chkpnt_1, {"my_key": "\x00abc"}, {})
+            assert saver.get_tuple(config).metadata["my_key"] == "abc"
+            assert (
+                list(saver.list(None, filter={"my_key": "abc"}))[0].metadata["my_key"]
+                == "abc"
+            )