NotificationsYou must be signed in to change notification settings
Fork34k
Star71.3k

gh-144001: Add ignorechars parameter to Base64 decoder#144009

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to ourterms of service andprivacy statement. We’ll occasionally send you account related emails.

Already on GitHub?Sign in to your account

Jump to bottom

Closed

moneebullah25 wants to merge6 commits intopython:mainfrommoneebullah25:gh-144001-add-ignorechars-base64

Closed

gh-144001: Add ignorechars parameter to Base64 decoder#144009

moneebullah25 wants to merge6 commits intopython:mainfrommoneebullah25:gh-144001-add-ignorechars-base64

Conversation

Copy link

Contributor

moneebullah25 commentedJan 18, 2026•
edited
Loading

Summary

Add theignorechars parameter tobinascii.a2b_base64() andbase64.b64decode()
When provided, only characters in this set will be silently ignored during decoding
Other non-base64 characters will cause abinascii.Error
Similar to the existingignorechars parameter inbase64.a85decode()

This addresses the feature request in#144001 where the existingstrict_mode/validate parameters are "all-or-nothing" - either all non-alphabet characters are rejected, or all are ignored. The newignorechars parameter allows selective filtering (e.g., ignoring whitespace while rejecting other invalid characters).

API

# Ignore only whitespace, reject other invalid charsbase64.b64decode(b'YWJj\n',ignorechars=b'\n')# OK: b'abc'base64.b64decode(b'YWJj!',ignorechars=b'\n')# Error# Strict: reject all non-base64base64.b64decode(b'YWJj\n',ignorechars=b'')# Error# Default behavior unchangedbase64.b64decode(b'YWJj\n')# OK: b'abc' (ignores all)