style: avoid a chained traceback on dns parsing error

diff --git a/psycopg/psycopg/conninfo.py b/psycopg/psycopg/conninfo.py
index 3b21f838f0972a243251a27e3895a8bec2ff9599..38d1f7dabc43d16a43e18b990156ca6b22f60c4c 100644 (file)
--- a/psycopg/psycopg/conninfo.py
+++ b/psycopg/psycopg/conninfo.py
@@ -95,7 +95,7 @@ def _parse_conninfo(conninfo: str) -> List[pq.ConninfoOption]:
     try:
         return pq.Conninfo.parse(conninfo.encode())
     except e.OperationalError as ex:
-        raise e.ProgrammingError(str(ex))
+        raise e.ProgrammingError(str(ex)) from None
 
 
 re_escape = re.compile(r"([\\'])")