Prevent ReDoS in Spanish sentence splitting regex #1084
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Gallaecio
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Jan 11, 2023
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Closing and reopening to re-trigger CI jobs… |
In Spanish, questions start with an upside down question mark: > ¿Vos bueno? This was already handled in the original regex, but the original regex was vulnerable for regular expression denial of service (ReDoS). In the new regex, we either search for normal end-of-sentence optionally followed by a ¿ or ¡, or a ¿ or ¡ on its own. A change is that the normal end-of-sentence (.!?;…) has to come before the ¡ or ¿, but I think this is acceptable. This PR also adds some Spanish test cases. These hit the sentence splitting logic, but the exact result of the splitting is not tested. Fixes scrapinghub#869
Consume whitespace if there is any, but still match if there isn't. This makes most sense for \n followed immediately by ¿. This also means we don't have to backtrack if there isn't any whitespace after a line ending.
Sjord
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I rebased to master. |
The previous code wouldn't remove multiple empty strings in a row, due to modifying the list during the loop. We use `filter` with the default identity function instead.
serhii73
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Jan 11, 2023
wRAR
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Jan 11, 2023
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We have a new release with this PR. Thank you @Sjord |
dotlambda
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In Spanish, questions start with an upside down question mark:
This was already handled in the original regex, but the original regex was vulnerable for regular expression denial of service (ReDoS). In the new regex, we either search for normal end-of-sentence optionally followed by a ¿ or ¡, or a ¿ or ¡ on its own. A change is that the normal end-of-sentence (.!?;…) has to come before the ¡ or ¿, but I think this is acceptable.
This PR also adds some Spanish test cases. These hit the sentence splitting logic, but the exact result of the splitting is not tested.
Fixes #869