fix: inline merchant field is not disabled for unreported per diem expense

src/libs/actions/TransactionInlineEdit.ts

@@ -27,7 +27,16 @@ import {
     shouldEnableNegative,
 } from '@libs/ReportUtils';
 import {hasEnabledTags} from '@libs/TagsOptionsListUtils';
-import {calculateTaxAmount, getCurrency, getOriginalTransactionWithSplitInfo, getTaxValue, isDistanceRequest, isExpenseUnreported, isScanning} from '@libs/TransactionUtils';
+import {
+    calculateTaxAmount,
+    getCurrency,
+    getOriginalTransactionWithSplitInfo,
+    getTaxValue,
+    isDistanceRequest,
+    isExpenseUnreported,
+    isPerDiemRequest,
+    isScanning,
+} from '@libs/TransactionUtils';
 import CONST from '@src/CONST';
 import ONYXKEYS from '@src/ONYXKEYS';
 import type {
@@ -422,15 +431,20 @@ function getTransactionEditPermissions({
                 return false;
             }
 
+            // Per diem amount is derived from the rate and cannot be edited
+            if (isPerDiemRequest(transaction)) {
+                return false;
+            }
+
             // Amount field shows "Scanning..." during SmartScan
             if (isTransactionScanning) {
                 return false;
             }
         }
 
         if (field === CONST.EDIT_REQUEST_FIELD.MERCHANT) {
-            // Distance expenses cannot have their merchant edited
-            if (isDistanceRequest(transaction)) {
+            // Distance and per diem expenses cannot have their merchant edited
+            if (isDistanceRequest(transaction) || isPerDiemRequest(transaction)) {
                 return false;
             }
 

tests/unit/inlineEditing/TransactionInlineEdit.test.ts

@@ -173,6 +173,36 @@ describe('getTransactionEditPermissions', () => {
         });
     });
 
+    describe('per diem requests', () => {
+        it('should disable amount and merchant for per diem requests', () => {
+            const perDiemTransaction: Transaction = {
+                ...baseTransaction,
+                reportID: CONST.REPORT.UNREPORTED_REPORT_ID,
+                comment: {
+                    type: CONST.TRANSACTION.TYPE.CUSTOM_UNIT,
+                    customUnit: {
+                        name: CONST.CUSTOM_UNITS.NAME_PER_DIEM_INTERNATIONAL,
+                    },
+                },
+            };
+
+            const permissions = getTransactionEditPermissions({
+                ...baseUnreportedParams,
+                transaction: perDiemTransaction,
+            });
+
+            expect(permissions).toMatchObject({
+                canEditCategory: true,
+                canEditDate: true,
+                canEditDescription: true,
+                canEditTag: true,
+                // Amount and merchant are derived from the rate and cannot be edited
+                canEditAmount: false,
+                canEditMerchant: false,
+            } satisfies TransactionEditPermissions);
+        });
+    });
+
     describe('split expenses', () => {
         it('should handle field permissions correctly for split expense children', () => {
             const splitTransaction: Transaction = {
@@ -360,6 +390,24 @@ describe('getTransactionEditPermissions', () => {
             } satisfies Partial<TransactionEditPermissions>);
         });
 
+        it('should respect per diem request restrictions', () => {
+            const permissions = getTransactionEditPermissions({
+                ...baseUnreportedParams,
+                transaction: {
+                    ...unreportedTransaction,
+                    comment: {
+                        type: CONST.TRANSACTION.TYPE.CUSTOM_UNIT,
+                        customUnit: {name: CONST.CUSTOM_UNITS.NAME_PER_DIEM_INTERNATIONAL},
+                    },
+                },
+            });
+
+            expect(permissions).toMatchObject({
+                canEditAmount: false,
+                canEditMerchant: false,
+            } satisfies Partial<TransactionEditPermissions>);
+        });
+
         it('should disable category editing when workspace selection is required', () => {
             const permissions = getTransactionEditPermissions({
                 ...baseUnreportedParams,