Fix: Stop splitting surrogate-pairs in diff-match-patch deltas #91
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dmsnell
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See google/diff-match-patch#80 There have been certain cases where consecutive surrogate pairs crash `diff-match-patch` when it's building the _delta string_. This is because the diffing algorithm finds a common prefix up to and including half of the surrogate pair match when three consecutive code points share the same high surrogate. ``` // before - \ud83d\ude4b\ud83d\ue4b // after - \ud83d\ude4b\ud83d\ue4c\ud83d\ude4b // deltas - eq \ud83d\ude4b\ud83d -> add \ude4c -> eq \ud83d \ude4b ``` This crashes when trying to encode the invalid sequence of UTF-16 code units into `URIEncode`, which expects a valid Unicode string. After the fix the delta groups are normalized to prevent this situation and the `node-simperium` library should be able to process those problematic changesets.
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See: Simperium/node-simperium#91 See: google/diff-match-patch#80 There have been certain cases where consecutive surrogate pairs crash `diff-match-patch` when it's building the _delta string_. This is because the diffing algorithm finds a common prefix up to and including half of the surrogate pair match when three consecutive code points share the same high surrogate. ``` // before - \ud83d\ude4b\ud83d\ue4b // after - \ud83d\ude4b\ud83d\ue4c\ud83d\ude4b // deltas - eq \ud83d\ude4b\ud83d -> add \ude4c -> eq \ud83d \ude4b ``` This crashes when trying to encode the invalid sequence of UTF-16 code units into `URIEncode`, which expects a valid Unicode string. After the fix the delta groups are normalized to prevent this situation and the `node-simperium` library should be able to process those problematic changesets. This patch updates the dependency on the patched version of `node-simperium`.
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* Fix: No more crashing/skipped changes for certain changes See: Simperium/node-simperium#91 See: google/diff-match-patch#80 There have been certain cases where consecutive surrogate pairs crash `diff-match-patch` when it's building the _delta string_. This is because the diffing algorithm finds a common prefix up to and including half of the surrogate pair match when three consecutive code points share the same high surrogate. ``` // before - \ud83d\ude4b\ud83d\ue4b // after - \ud83d\ude4b\ud83d\ue4c\ud83d\ude4b // deltas - eq \ud83d\ude4b\ud83d -> add \ude4c -> eq \ud83d \ude4b ``` This crashes when trying to encode the invalid sequence of UTF-16 code units into `URIEncode`, which expects a valid Unicode string. After the fix the delta groups are normalized to prevent this situation and the `node-simperium` library should be able to process those problematic changesets. This patch updates the dependency on the patched version of `node-simperium`.
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See google/diff-match-patch#80
There have been certain cases where consecutive surrogate pairs crash
diff-match-patchwhen it's building the delta string. This isbecause the diffing algorithm finds a common prefix up to and including
half of the surrogate pair match when three consecutive code points
share the same high surrogate.
This crashes when trying to encode the invalid sequence of UTF-16 code
units into
URIEncode, which expects a valid Unicode string.After the fix the delta groups are normalized to prevent this situation
and the
node-simperiumlibrary should be able to process thoseproblematic changesets.