New submission from Andrei Kulakov <andrei....@gmail.com>:
In csv.DictWriter, the arg `extrasaction` case is handled inconsistently: - if it's misspelled, e.g. ignor instead of 'ignore', a ValueError is raised by the __init__ method. - if it's 'Ignore', 'IGNORE', it will work properly - if it's 'raise', it will also work properly - BUT: if it's 'Raise' or 'RAISE', it will have the same effect as 'ignore' The code is here: https://github.com/python/cpython/blob/main/Lib/csv.py#L135-L146 [ins] In [1]: from csv import DictWriter [ins] In [4]: d=DictWriter(open('testcsv','w'),'abc',extrasaction='IGNORE') [ins] In [5]: list(d._dict_to_list(dict(d=1))) Out[6]: ['', '', ''] [ins] In [7]: d=DictWriter(open('testcsv','w'),'abc',extrasaction='RAISE') [ins] In [8]: list( d._dict_to_list(dict(d=1)) ) Out[8]: ['', '', ''] [ins] In [9]: d=DictWriter(open('testcsv','w'),'abc',extrasaction='TEST') --------------------------------------------------------------------------- ValueError Traceback (most recent call last) <ipython-input-9-953d1100c7f9> in <module> ----> 1 d=DictWriter(open('testcsv','w'),'abc',extrasaction='TEST') /usr/local/Cellar/python@3.9/3.9.1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/csv.py in __init__(self, f, fieldnames, restval, extrasaction, dialect, *args, **kwds) 134 self.restval = restval # for writing short dicts 135 if extrasaction.lower() not in ("raise", "ignore"): --> 136 raise ValueError("extrasaction (%s) must be 'raise' or 'ignore'" 137 % extrasaction) 138 self.extrasaction = extrasaction ValueError: extrasaction (TEST) must be 'raise' or 'ignore' [ins] In [10]: d=DictWriter(open('testcsv','w'),'abc',extrasaction='raise') [ins] In [11]: list( d._dict_to_list(dict(d=1)) ) --------------------------------------------------------------------------- ValueError Traceback (most recent call last) <ipython-input-11-1fde207e1805> in <module> ----> 1 list( d._dict_to_list(dict(d=1)) ) /usr/local/Cellar/python@3.9/3.9.1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/csv.py in _dict_to_list(self, rowdict) 147 wrong_fields = rowdict.keys() - self.fieldnames 148 if wrong_fields: --> 149 raise ValueError("dict contains fields not in fieldnames: " 150 + ", ".join([repr(x) for x in wrong_fields])) 151 return (rowdict.get(key, self.restval) for key in self.fieldnames) ValueError: dict contains fields not in fieldnames: 'd' ---- I propose to accept any case of Raise, RAISE, etc, to have the effect of 'raise'. I can put up the PR if that sounds good. ---------- components: Library (Lib) messages: 396536 nosy: andrei.avk priority: normal severity: normal status: open title: csv.DictWriter: inconsistency in handling of extrasaction arg versions: Python 3.10, Python 3.11, Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue44512> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
