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A handler can return Err(SuspensionRequest) to park the current rewritable unit on the heap and exit write()/end() with the non-poisoning RewritingError::Suspended; HtmlRewriter::resume() continues from a StateMachineBookmark. - take_owned() on each rewritable unit deep-copies borrowed byte slices so the unit outlives the write() stack frame - Arena::shift advances a start offset instead of memmoving the tail (a suspended rewrite re-feeds its unconsumed tail on every resume) - the pending captured-text flush is hoisted from Dispatcher::handle_tag into the lexer actions so every suspension point has a uniform shape - end_mut() is the non-consuming end() for a rewriter that may suspend in a document-end handler Bun uses this so an async JS content handler can suspend the rewrite and resume it from a promise reaction instead of spinning a nested event loop inside write(). See oven-sh/bun#36733.
The upstream ci.yml triggers on push: branches: [master] only, so an additive bun.yml runs cargo test --features=integration_test on pushes/PRs to bun without touching ci.yml (keeps rebases onto upstream clean).
…epth
The selector-VM open-element stack had two per-token scans that go
quadratic (or worse) on pathological nesting:
* Stack::pop_up_to did a full rposition() over the open stack for
every end tag. A stray end tag that matches nothing still walked
the whole stack, so N unclosed opens plus N stray closes was O(N^2):
"<a></b>".repeat(100_000) (~700 KB) burned ~25s of CPU.
* try_exec_hereditary_jumps_without_attrs walked every ancestor and
re-executed its hereditary_jumps for every start tag. For a selector
like "div div" over N nested <div>s every item carries the same
address range, so the walk is O(depth) per tag and O(N^2) overall;
k-arm chains ("div div div") compound to O(N^k).
Both paths are reachable from HtmlRewriter with any element-handler
registration, so untrusted HTML can pin a CPU core via sub-MB input.
Memory stays linear so max_allowed_memory_usage does not bound it.
Changes:
* Stack now keeps open_name_counts: HashMap<LocalName, usize> so
pop_up_to rejects a name not on the stack in O(1). When the name is
present the rposition scan length equals the subsequent drain
length, so total scan work over a document is bounded by total
pushes.
* Stack now keeps active_hereditary_jumps: Vec<(AddressRange, usize)>,
the distinct hereditary-jump ranges currently contributed by any
open item, each paired with the shallowest depth that introduced it.
Descendant matching iterates this flat list (bounded by program
size, not depth) and pop_up_to prunes it by depth. The per-item
has_ancestor_with_hereditary_jumps flag and the
HereditaryJumpPtr.stack_offset resume coordinate are removed.
* LocalName gets a manual Hash impl that ASCII-lowercases the Bytes
arm so it agrees with the existing case-insensitive PartialEq.
Without this, keying a HashMap on LocalName is unsound for any name
that falls off LocalNameHash (custom elements, >12 chars, chars
outside a-zA-Z1-6). This also fixes the same latent contract
violation in TypedChildCounterMap.
Re-executing the same address range against the same start tag was
already a no-op after the matched-id set union in add_execution_branch,
so dedup-once execution is observationally equivalent.
…et_text. Previously `Comment::set_text` only rejected the canonical `-->` terminator, but a WHATWG-conformant browser also closes a comment on three more byte sequences: 1. `--!>` anywhere in the body (comment-end-bang state). 2. A leading `>` (abrupt-closing-of-empty-comment from comment-start). 3. A leading `->` (abrupt-closing-of-empty-comment from comment-start-dash). (cherry picked from commit ba25359) Port to the v2.7.2 base: `set_text` keeps `BytesCow::from_str_without_replacements` plus `into_owned()`, and the CHANGELOG.md hunk is dropped because this branch has no v3.0.0 section.
This was referenced Sep 13, 2026
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Closing: the The port for the v2.7.2 lineage is kept for Bun's pin while Bun's main is on that lineage: |
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Problem
Comment::set_textrejects-->only (src/rewritable_units/tokens/comment.rs:70). The HTML tokenizer also ends a comment at--!>(comment end bang state), and ends an empty comment at<!-->and<!--->(abrupt closing of empty comment). So text with--!>anywhere, or with a leading>or->, ends the comment early and the rest of the text becomes markup:set_text("x--!><img src=x onerror=alert(1)>")serializes to<!--x--!><img src=x onerror=alert(1)>-->.Fix
bun, with-x.set_textreturnsCommentTextError::CommentClosingSequencefor all four forms. The error text is upstream's new one:Comment text shouldn't contain a comment-closing sequence.set_textkeeps the v2.7.2BytesCow::from_str_without_replacements(..)plusinto_owned()(upstream had moved toowned_from_str_without_replacements). TheCHANGELOG.mdhunk is dropped because this branch has no v3.0.0 section.cargo test --features=integration_test(172 + 3 + 32 + 2 pass). In Bun,comment.text = "x--!>...",">..."and"->..."now throw, and near misses such as--!,x--,a->bstill round-trip.Please merge without squash, or tell me the new sha. Bun pins this branch by commit in
scripts/build/deps/lolhtml.ts.Bun side: oven-sh/bun#42646