GeezerVison is showing github.com — gh-159739: Validate newline replacement in TextIOWrapper.write by jelle-openai · Pull Request #160191 · python/cpython
Conversation
jelle-openai
commented
Oct 22, 2026
•
edited by bedevere-app
Bot
Loading
Uh oh!
There was an error while loading. Please reload this page.
A str subclass can override replace() and return a non-string while TextIOWrapper.write() translates newlines. The C implementation then treats the result as Unicode and can crash. Reject an invalid replacement with TypeError. Backport to 3.15 and 3.14; on 3.14, put the regression test in Lib/test/test_io.py.
Sorry, something went wrong.
Uh oh!
There was an error while loading. Please reload this page.
A str subclass can override replace() and return a non-string while TextIOWrapper.write() translates newlines. The C implementation then treats the result as Unicode and can crash. Reject an invalid replacement with TypeError. Backport to 3.15 and 3.14; on 3.14, put the regression test in Lib/test/test_io.py.
Uh oh!
There was an error while loading. Please reload this page.
Sorry, something went wrong.
Uh oh!
There was an error while loading. Please reload this page.
JelleZijlstra
pushed a commit
that referenced
this pull request
Oct 24, 2026
…GH-160191) (#160487)
A str subclass can override replace() and return a non-string while TextIOWrapper.write() translates newlines. The C implementation then treats the result as Unicode and can crash. Reject an invalid replacement with TypeError. Backport to 3.15 and 3.14; on 3.14, put the regression test in Lib/test/test_io.py.
(cherry picked from commit c6796a1)
Uh oh!
There was an error while loading. Please reload this page.
Assignees
No one assigned
Milestone
No milestone
Development
Successfully merging this pull request may close these issues.
Uh oh!
There was an error while loading. Please reload this page.
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.