From cd492d43a2980faf0ef4a3f99c665023a506414c Mon Sep 17 00:00:00 2001 From: Sam Ezeh Date: Thu, 25 Aug 2022 11:13:24 +0100 Subject: gh-76728: Coerce DictReader and DictWriter fieldnames argument to a list (GH-32225) --- Lib/csv.py | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Lib/csv.py') diff --git a/Lib/csv.py b/Lib/csv.py index bfc850ee96d..0de5656a4ee 100644 --- a/Lib/csv.py +++ b/Lib/csv.py @@ -81,6 +81,8 @@ register_dialect("unix", unix_dialect) class DictReader: def __init__(self, f, fieldnames=None, restkey=None, restval=None, dialect="excel", *args, **kwds): + if fieldnames is not None and iter(fieldnames) is fieldnames: + fieldnames = list(fieldnames) self._fieldnames = fieldnames # list of keys for the dict self.restkey = restkey # key to catch long rows self.restval = restval # default value for short rows @@ -133,6 +135,8 @@ class DictReader: class DictWriter: def __init__(self, f, fieldnames, restval="", extrasaction="raise", dialect="excel", *args, **kwds): + if fieldnames is not None and iter(fieldnames) is fieldnames: + fieldnames = list(fieldnames) self.fieldnames = fieldnames # list of keys for the dict self.restval = restval # for writing short dicts if extrasaction.lower() not in ("raise", "ignore"): -- cgit v1.2.3