fix(generate): warn users when extra rule can lead to parser hang#4750
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WillLillis merged 1 commit intotree-sitter:masterfrom Aug 30, 2025
Merged
fix(generate): warn users when extra rule can lead to parser hang#4750WillLillis merged 1 commit intotree-sitter:masterfrom
WillLillis merged 1 commit intotree-sitter:masterfrom
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amaanq
approved these changes
Aug 29, 2025
clason
reviewed
Aug 29, 2025
When a *named* rule in the extras is able to match the empty string, parsing can hang in certain situations (i.e. near EOF).
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The problem
When a named rule in extras is able to match the empty string, parsing can hang in certain situations (i.e. near EOF). This is demonstrated by #4405.
The Solution
There isn't a great way to fix the actual hang in the core lib. An easy workaround for grammar authors is to simply inline the rule in question into extras. The CLI will now warn during generation if such a case is detected.
tree-sitter parsehangs parsing string literal #4405