From: Evan You <yyx990803@gmail.com>
Date: Wed, 9 Nov 2022 12:50:02 +0000 (+0800)
Subject: fix(watch): ensure oldValue in multi-source watcher is always an array
X-Git-Tag: v3.2.43~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=23e85e21a50926c48dea4f978e212e4301c20037;p=thirdparty%2Fvuejs%2Fcore.git

fix(watch): ensure oldValue in multi-source watcher is always an array

fix #7070
---

diff --git a/packages/runtime-core/__tests__/apiWatch.spec.ts b/packages/runtime-core/__tests__/apiWatch.spec.ts
index c9db365736..029146b520 100644
--- a/packages/runtime-core/__tests__/apiWatch.spec.ts
+++ b/packages/runtime-core/__tests__/apiWatch.spec.ts
@@ -183,10 +183,10 @@ describe('api: watch', () => {
     let called = false
     watch(
       [a, b],
-      (newVal, oldVal) => {
+      ([newA, newB], [oldA, oldB]) => {
         called = true
-        expect(newVal).toMatchObject([undefined, undefined])
-        expect(oldVal).toBeUndefined()
+        expect([newA, newB]).toMatchObject([undefined, undefined])
+        expect([oldA, oldB]).toMatchObject([undefined, undefined])
       },
       { immediate: true }
     )
diff --git a/packages/runtime-core/src/apiWatch.ts b/packages/runtime-core/src/apiWatch.ts
index 180843cf74..99445be77d 100644
--- a/packages/runtime-core/src/apiWatch.ts
+++ b/packages/runtime-core/src/apiWatch.ts
@@ -335,7 +335,7 @@ function doWatch(
           // pass undefined as the old value when it's changed for the first time
           oldValue === INITIAL_WATCHER_VALUE ||
           (isMultiSource && oldValue[0] === INITIAL_WATCHER_VALUE)
-            ? undefined
+            ? []
             : oldValue,
           onCleanup
         ])