fix(history): tolerate non-array message content in blocksToText - #262
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dex0shubham wants to merge 1 commit into
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fix(history): tolerate non-array message content in blocksToText#262dex0shubham wants to merge 1 commit into
dex0shubham wants to merge 1 commit into
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blocksToText handled the string case then fell into `for (const blk of content)`,
assuming an array. An untrusted body carrying `content: null` (or any non-array)
makes the for...of throw `TypeError: content is not iterable`. The collapse path
reaches it with raw, unvalidated content (messagesToHistorySegments -> blocksToText
on assistant turns, and via withoutTypedUserText which returns null unchanged for
user turns), so a single `{"role":"assistant","content":null}` turn 502s the whole
request ("pxpipe transform failed").
Every sibling serializer/scanner in this module already guards this
(findClosedPrefixBoundary, withoutTypedUserText, splitUserTyped, messageCacheControl
all `if (!Array.isArray(...))`). Add the same guard so a malformed turn serializes
to empty and passes through.
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Problem
blocksToText(src/core/history.ts) handles thestringcase, then does:assuming an array. An untrusted request body can carry a non-array
content(e.g.{"role":"assistant","content":null}), andfor...of nullthrowsTypeError: content is not iterable.The collapse path reaches this with raw, unvalidated content:
messagesToHistorySegmentscallsblocksToText(m.content)for assistant turns (and viawithoutTypedUserText, which returnsnullunchanged, for user turns), andreq.messagesis only checked with an outerArray.isArray— individualcontentfields are never validated. The throw propagates out oftransformRequestand is turned into a 502 "pxpipe transform failed" at the proxy, so one malformed turn fails the whole request.Every sibling in the module already guards exactly this shape and passes it through:
findClosedPrefixBoundary,withoutTypedUserText,splitUserTyped,messageCacheControl(and the OpenAI-path twinchatContentToText).blocksToTextwas the lone exception.Fix
Add the same
!Array.isArray(content)guard, returning''— a malformed turn serializes to empty and passes through instead of 502ing.Added a unit test (
blocksToText(null)/undefined), verified it throws on the old code and passes with the fix.Full suite green (1207/1207);
typecheckclean.