我正在使用 firebase 云功能和 firestore 交易来减少基于购买的产品的可用数量。部署时,它返回错误“错误 TS7030:并非所有代码路径都返回值”
这是代码
import * as functions from 'firebase-functions';
import * as admin from 'firebase-admin';
admin.initializeApp();
const db = admin.firestore()
exports.newOrder = functions.firestore
.document('orders/{orderId}')
.onCreate(async (snap, context) => {
    try {
        const data = snap.data();
        if (data === undefined) return null
        const itemList = data.list as Array<any>
        const productId: Set<string> = new Set<string>();
        itemList.forEach((item) => {
            productId.add(item.id)
        })
        return db.runTransaction(async t => {
            const promises: Promise<admin.firestore.DocumentSnapshot>[] = []
            productId.forEach(i => {
                const p = admin.firestore().doc('Products/' + …Run Code Online (Sandbox Code Playgroud) typescript tslint google-cloud-functions google-cloud-firestore