fix(history): return undefined when there is no history sync notification

[jlucaso1]

getHistoryMsg threw a Boom 400 for any message that is not a history sync — which is most messages.

That breaks the shape a drop-in caller writes:

const h = getHistoryMsg(msg)
if (!h) return   // never reached: the line above already threw

Upstream returns undefined here. Absent is the ordinary case for this helper, not an error condition: every message that is not a history sync takes that path.

Change

Returns undefined, and the return type says | undefined so a caller who ignores it gets a type error rather than a runtime one. The Boom import is dropped along with the throw — it was the only use in the file.

The compatibility test asserted the throw; it now asserts the value, and covers two cases it did not before: a message with no content at all, and a missing argument.

assert.equal(getHistoryMsg({ conversation: 'not a history sync' }), undefined)
assert.equal(getHistoryMsg({}), undefined)
assert.equal(getHistoryMsg(undefined as never), undefined)

Registry

get-history-msg-throws-instead-of-undefined is deleted. After the change the deep pure:getHistoryMsg target runs 5001 inputs with 0 findings and 0 excused, so the entry excuses nothing and an allowlist that outlives its divergence is how the same bug comes back. Open findings 22 → 21.

Breaking change

Callers who relied on the throw to signal "not a history sync" — via try/catch — stop seeing it. That behaviour was the defect, and no caller inside this repository depended on it: getHistoryMsg has no internal call sites, only the export and its test.

Validation

tsc --noEmit, oxlint, oxfmt --check clean. npm test 1182 pass / 0 fail. npm run fuzz 185 pass / 0 fail.

🤖 Generated with Claude Code

https://claude.ai/code/session_01RvtvVVWQs8AeBqSzS1JpCg

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Generated by Claude Code

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Summary by cubic

Return undefined from getHistoryMsg when a message has no history-sync notification, matching upstream and preventing crashes in common code paths. This fixes the drop-in pattern where callers check for absence instead of handling exceptions.

• Bug Fixes

  • getHistoryMsg returns undefined instead of throwing for non-history messages.
  • Removed Boom usage and updated tests (added no-content and missing-arg cases).
  • Deleted the obsolete divergence registry entry.

• Migration

  • If you relied on an exception to signal “not a history sync,” replace try/catch with an undefined check.

^{Written for commit cb11209. Summary will update on new commits.}

Summary by CodeRabbit

• Bug Fixes

  • Updated history message handling to return no result for messages without history data instead of raising an error.
  • Preserved normalization for messages containing valid history notifications.

• Tests

  • Updated compatibility checks to cover missing, empty, and undefined message inputs.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: edefc8e3-d86c-46c6-87fa-164d575f339d

📥 Commits

Reviewing files that changed from the base of the PR and between a7ffb68 and cb11209.

📒 Files selected for processing (3)

• src/Utils/process-history-message.ts
• src/__fuzz__/harness/divergence.ts
• src/__tests__/public-helpers-compatibility.test.ts

💤 Files with no reviewable changes (1)

• src/fuzz/harness/divergence.ts

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📝 Walkthrough

Walkthrough

getHistoryMsg now returns undefined for messages without history-sync notifications. The public compatibility test covers these inputs, and the fuzz divergence allowlist entry is removed.

Changes

History message behavior

Layer / File(s)	Summary
History message contract and validation src/Utils/process-history-message.ts, src/__tests__/public-helpers-compatibility.test.ts, src/__fuzz__/harness/divergence.ts	getHistoryMsg returns a normalized notification when present and undefined when absent. Compatibility tests cover non-history messages, empty objects, and undefined. The obsolete fuzz divergence entry is removed.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• oxidezap/baileyrs#43: Introduced the related getHistoryMsg fuzz-divergence expectation.

Poem

A rabbit found a message bare,
No history notification there.
“Return undefined,” said the hare,
The tests now check the answer fair.
No Boom hops through the codebase air.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: returning undefined when no history sync notification exists.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

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