Fix using() to not mutate closure-captured kwargs dict#3044
Merged
birkenfeld merged 1 commit intopygments:masterfrom Feb 20, 2026
Merged
Fix using() to not mutate closure-captured kwargs dict#3044birkenfeld merged 1 commit intopygments:masterfrom
birkenfeld merged 1 commit intopygments:masterfrom
Conversation
using() callbacks called kwargs.update(lexer.options), permanently mutating the dict captured from the class definition. This caused two problems: 1. Accumulated state across calls — the dict grew with each invocation, mixing in options from previous instances. 2. Wrong precedence — lexer.options (parent) overwrote kwargs (explicit), so e.g. using(PhpLexer, startinline=True) could be overridden by the parent lexer's startinline=False. Use a fresh copy per call, with explicit kwargs taking priority over inherited options.
Member
|
Makes sense to me, thanks. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Problem
using()callbacks mutate the closure-capturedkwargsdict viakwargs.update(lexer.options). This causes two issues:State accumulation: The dict grows with each invocation, mixing in options from previous lexer instances.
Wrong precedence:
kwargs.update(lexer.options)gives the parent lexer's generic options priority over the explicitly-provided kwargs. For example,using(PhpLexer, startinline=True)can be overridden if the parent lexer was created withstartinline=False.Fix
Create a fresh dict per callback invocation. Start from lexer.options and then overlay explicit kwargs, so user-specified arguments take priority: