NousResearch/hermes-agent

LSP document sync broken by non-BMP characters

Cluster 116094. Data as of

Nothing open on GitHub. Fix merged in #116790 on 20 Sep 2026. Check it covers your case.

The short answer

0open issues
0open PRs
3items grouped
Known?
Yes. 3 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #116790. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #116790. That is separate from the fix event.
Still open
Nothing open on GitHub.

These issues and fixes address a bug where LSP incremental text synchronization produces stale or incorrect document state when the content contains non-BMP (multi-byte) Unicode characters, due to incorrect UTF-16 code unit handling in replacement ranges.

Open issues0

No open issues.

Open PRs0

No open pull requests.

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

  • #116790 fix(lsp): incremental servers keep an exact document mirror after non-BMP characters (#116094, salvage #116097)

    merged to main

    files: agent/lsp/client.py, tests/agent/lsp/_mock_lsp_server.py, tests/agent/lsp/test_incremental_unicode.py

1 PR closed without merging

From the close comments: merged via another change 1

  • #116097 fix(lsp): use UTF-16 units for document replacement ranges · merged via another change → d23d6e8, #116790, #116094, #116097
Closed issues · 1
  • Closed#116094bug(lsp): incremental replacements leave stale text after non-BMP characters
How this cluster was grouped
  • Link evidence (structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
  • Pairwise link density 0.67: the share of item pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. 1.00 means every pair is linked.

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At a glance

Merged PRs
#116790
Closed issues
1
Attempts
1 PR closed without merging
Fix link checked
20 Sep 2026

For your agent

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