[3.10] bpo-44630: Fix assertion errors in csv module (GH-27127) (GH-27129)
Fix incorrect handling of exceptions when interpreting dialect objects in
the csv module. Not clearing exceptions between calls to
PyObject_GetAttrString() causes assertion failures in pydebug mode (or with
assertions enabled).
Add a minimal test that would've caught this (passing None as dialect, or
any object that isn't a csv.Dialect subclass, which the csv module allows
and caters to, even though it is not documented.) In pydebug mode, the test
triggers the assertion failure in the old code.
Contributed-By: T. Wouters [Google]
(cherry picked from commit 0093876328afa330224c9d887c18dee0b3117852)
Co-authored-by: T. Wouters <thomas@python.org>
Automerge-Triggered-By: GH:gpshead
diff --git a/Lib/test/test_csv.py b/Lib/test/test_csv.py
index 225f5c7..18b86aa 100644
--- a/Lib/test/test_csv.py
+++ b/Lib/test/test_csv.py
@@ -458,9 +458,15 @@ class testC(csv.excel):
class testUni(csv.excel):
delimiter = "\u039B"
+ class unspecified():
+ # A class to pass as dialect but with no dialect attributes.
+ pass
+
csv.register_dialect('testC', testC)
try:
self.compare_dialect_123("1,2,3\r\n")
+ self.compare_dialect_123("1,2,3\r\n", dialect=None)
+ self.compare_dialect_123("1,2,3\r\n", dialect=unspecified)
self.compare_dialect_123("1\t2\t3\r\n", testA)
self.compare_dialect_123("1:2:3\r\n", dialect=testB())
self.compare_dialect_123("1|2|3\r\n", dialect='testC')