[kixelated]

Problem

When a publisher resets a superseded group, it sends stream code Old. The reader sees that as Error::Stream(StreamError::Old).

#5677 narrowed the lost-group match in these readers to the locally raised variants (Error::Old | Evicted | Lagged | GroupTooLarge):

• moq-json snapshot consumer
• moq-json window consumer
• moq-flate snapshot consumer

So a wire reset now surfaces as a fatal error. A hang catalog is a long-lived snapshot group, which makes this hit catalog readers. For example, moq-hls's watch_catalog gives up on the broadcast and never resubscribes, so a recording of that broadcast stays empty.

It is intermittent: it needs the publisher to supersede the catalog group while a relay-side reader is attached. A relay recorder loop reproduced it about once in 75 broadcasts. Instrumented, the failing read was Stream(Old).

Fix

Classify the error by StreamError::from(&err), the same mapping the wire uses, so the local and wire spellings count as the same loss:

• Old
• Evicted
• TooFarBehind
• GroupTooLarge

The JS consumers already classify by StreamCode, so this brings Rust in line.

There is no public API or wire change.

Tests

The existing lost-group tests now run once per spelling: local Error::Old, then the wire Error::Stream(StreamError::Old). The window test also covers the wire TooFarBehind, Evicted and GroupTooLarge. All three tests fail without the fix.

just check passes except nix flake check. That step builds the github-runner image, which needs user namespaces this host's Nix sandbox refuses. The diff touches no Nix. I ran every stage after it by hand, plus just rs test-changed: 4364, 516 and 224 tests, all passing.

(Written by Claude Opus 5.5)

🤖 Generated with Claude Code

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📥 Commits

Reviewing files that changed from the base of the PR and between d20d2dd and 221cc5b.

📒 Files selected for processing: 6

• rs/moq-flate/src/snapshot/consumer.rs
• rs/moq-flate/src/snapshot/mod.rs
• rs/moq-json/src/snapshot/consumer.rs
• rs/moq-json/src/snapshot/mod.rs
• rs/moq-json/src/window/consumer.rs
• rs/moq-json/src/window/mod.rs

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-21T19:59:02.531270Z	221cc5b	PR opened

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[kixelated]

Merge summary: no changes made during /quest-merge.

• Review: Codex reviewed head 221cc5bc2a64cb87516083b79206231cf6eb068a with no findings (+1). CodeRabbit was rate limited.
• CI: all PR-level checks pass; Check runs in the merge queue.
• Verified: StreamError::from(&Error) maps only Old, Evicted, Lagged and GroupTooLarge (plus their wire spellings) to the four matched codes, so local behavior is unchanged and wire resets now count as the same loss.
• Other readers (moq-hls rendition, moq-ffi, moq-cli) already match both spellings.

Enabling auto-merge on the head above.

(Written by Claude Opus 5.5)