From fb099c9ef134166ecaf3905c0d8b2995245f3ded Mon Sep 17 00:00:00 2001 From: R David Murray Date: Tue, 19 Nov 2013 13:16:20 -0500 Subject: [PATCH] #19449: Handle non-string keys when generating 'fieldnames' error. csv was handling non-string keys fine except for the error message generated when a non-string key was not in 'fieldnames'. Fix by Tomas Grahn, full patch-with-test by Vajrasky Kok (tweaked slightly). --- Lib/csv.py | 2 +- Lib/test/test_csv.py | 12 ++++++++++++ Misc/NEWS | 3 +++ 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/Lib/csv.py b/Lib/csv.py index da3bc44e7ac..a56eed88c86 100644 --- a/Lib/csv.py +++ b/Lib/csv.py @@ -146,7 +146,7 @@ class DictWriter: wrong_fields = [k for k in rowdict if k not in self.fieldnames] if wrong_fields: raise ValueError("dict contains fields not in fieldnames: " - + ", ".join(wrong_fields)) + + ", ".join([repr(x) for x in wrong_fields])) return [rowdict.get(key, self.restval) for key in self.fieldnames] def writerow(self, rowdict): diff --git a/Lib/test/test_csv.py b/Lib/test/test_csv.py index 976e6205b71..479ebd9bf22 100644 --- a/Lib/test/test_csv.py +++ b/Lib/test/test_csv.py @@ -570,6 +570,18 @@ class TestDictFields(unittest.TestCase): fileobj = StringIO() self.assertRaises(TypeError, csv.DictWriter, fileobj) + def test_write_fields_not_in_fieldnames(self): + with TemporaryFile("w+", newline='') as fileobj: + writer = csv.DictWriter(fileobj, fieldnames = ["f1", "f2", "f3"]) + # Of special note is the non-string key (issue 19449) + with self.assertRaises(ValueError) as cx: + writer.writerow({"f4": 10, "f2": "spam", 1: "abc"}) + exception = str(cx.exception) + self.assertIn("fieldnames", exception) + self.assertIn("'f4'", exception) + self.assertNotIn("'f2'", exception) + self.assertIn("1", exception) + def test_read_dict_fields(self): with TemporaryFile("w+") as fileobj: fileobj.write("1,2,abc\r\n") diff --git a/Misc/NEWS b/Misc/NEWS index 897bbc23d7a..4278e952f54 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -13,6 +13,9 @@ Core and Builtins Library ------- +- Issue #19449: in csv's writerow, handle non-string keys when generating the + error message that certain keys are not in the 'fieldnames' list. + - Fix test.support.bind_port() to not cause an error when Python was compiled on a system with SO_REUSEPORT defined in the headers but run on a system with an OS kernel that does not support that reasonably new socket option.