bpo-34736: improve error message for invalid length b64decode inputs (GH-9563)
Improvements:
1. Include the number of valid data characters in the error message.
2. Mention "number of data characters" rather than "length".
https://bugs.python.org/issue34736
(cherry picked from commit 1fba2ffc37da52c08db51fe4360459990b0311c9)
Co-authored-by: Tal Einat <taleinat+github@gmail.com>
diff --git a/Lib/test/test_binascii.py b/Lib/test/test_binascii.py
index 7418a9ce9..8e37d55 100644
--- a/Lib/test/test_binascii.py
+++ b/Lib/test/test_binascii.py
@@ -3,6 +3,7 @@
import unittest
import binascii
import array
+import re
# Note: "*_hex" functions are aliases for "(un)hexlify"
b2a_functions = ['b2a_base64', 'b2a_hex', 'b2a_hqx', 'b2a_qp', 'b2a_uu',
@@ -127,7 +128,10 @@
# Test base64 with invalid number of valid characters (1 mod 4)
def assertInvalidLength(data):
- with self.assertRaisesRegex(binascii.Error, r'(?i)invalid.+length'):
+ n_data_chars = len(re.sub(br'[^A-Za-z0-9/+]', br'', data))
+ expected_errmsg_re = \
+ r'(?i)Invalid.+number of data characters.+' + str(n_data_chars)
+ with self.assertRaisesRegex(binascii.Error, expected_errmsg_re):
binascii.a2b_base64(self.type2test(data))
assertInvalidLength(b'a')