Write a SuiteScript 2.x script to set lot number and bin assignments on an Item Receipt subrecord (InventoryDetail) when receiving components against a work order

Verified steps

1. Load or create the item receipt record in dynamic mode: var rec = record.load({type: record.Type.ITEM_RECEIPT, id: receiptId, isDynamic: true}).
2. Select the target line using rec.selectLine({sublistId: 'item', line: lineIndex}) before accessing the inventory detail subrecord.
3. Get the subrecord: var invDetail = rec.getCurrentSublistSubrecord({sublistId: 'item', fieldId: 'inventorydetail'}).
4. Add an inventory assignment line: invDetail.selectNewLine({sublistId: 'inventoryassignment'}); invDetail.setCurrentSublistValue({sublistId: 'inventoryassignment', fieldId: 'receiptinventorynumber', value: '<lot>'}); invDetail.setCurrentSublistValue({sublistId: 'inventoryassignment', fieldId: 'quantity', value: qty}); invDetail.commitLine({sublistId: 'inventoryassignment'}).
5. Commit the parent line with rec.commitLine({sublistId: 'item'}) after setting the subrecord, then call rec.save().
6. Validate that the feature 'MULTILOCINVT' or 'LOTNUMBEREDINVENTORY' is enabled for the item; otherwise the inventorydetail subrecord field will be null.