Fix vacation delegate split creating phantom self-DM reports by MelvinBot · Pull Request #84541 · Expensify/App

MelvinBot · 2026-03-09T08:34:03Z

Explanation of Change

When a vacation delegate splits an expense, getMoneyRequestParticipantsFromReport() tries to look up the owner's policy expense chat via getReportOrDraftReport(report.chatReportID). However, vacation delegates don't have the expense owner's policy expense chat in their Onyx store (unlike copilot delegation, vacation delegation doesn't switch sessions). This causes chatReport to be undefined, and the function falls through to the else branch which returns an empty participants array [].

This empty array cascades through the split flow:

participants.at(0) ?? ({} as Participant) coerces [] to {}
Number(undefined) produces NaN for payerAccountID
getChatByParticipants([NaN, payeeAccountID]) finds no match
buildOptimisticChatReport creates phantom chat reports with NaN participants
These phantom reports appear as duplicate self-DMs in the LHN

The fix adds a fallback branch in getMoneyRequestParticipantsFromReport(): when the chat report is missing from Onyx but the report is a known expense report with chatReportID and policyID, we construct the participant directly from the expense report's own metadata. This mirrors the same participant shape that the function would produce if the policy expense chat were present.

Fixed Issues

$ #76671
PROPOSAL: #76671 (comment)

Tests

Set up 4 accounts in a workspace: Account A (owner), Account B (approver), Account C (vacation delegate), Account D (submitter)
As Account A, invite B, C, D to the workspace and set B as approver
As Account B, set Account C as vacation delegate
As Account D, submit an expense to the workspace chat
Log in as Account C (the vacation delegate)
Navigate to the expense report, open the expense detail
Tap "More" > "Split" > "Save"
Navigate to Inbox
Verify there are NO self-DMs in the LHN from the split action
Verify no infinite loading headers appear

Verify that no errors appear in the JS console

Offline tests

N/A - This fix addresses participant resolution logic that runs during the optimistic data creation phase. Offline behavior is unchanged since the split flow already handles optimistic updates.

QA Steps

Set up 4 accounts in a workspace: Account A (owner), Account B (approver), Account C (vacation delegate), Account D (submitter)
As Account A, invite B, C, D to the workspace and set B as approver
As Account B, set Account C as vacation delegate
As Account D, submit an expense to the workspace chat
Log in as Account C (the vacation delegate)
Navigate to the expense report, open the expense detail
Tap "More" > "Split" > "Save"
Navigate to Inbox
Verify there are NO duplicate self-DMs in the LHN
Verify no infinite loading headers appear when clicking any chat
Also verify that non-delegate splits still work normally (no regression)

Verify that no errors appear in the JS console