From 30fd4b59c981f806f862bcf8621c0b71da5890af Mon Sep 17 00:00:00 2001
From: BeiYuShuiGuoLvDeKongQi <958414905@qq.com>
Date: Sun, 26 Apr 2020 21:38:53 +0800
Subject: [PATCH 1/2] fix(namespace): apply every namespace in slot when call
 applyNS (#11315)

---
 src/core/vdom/create-element.ts               | 11 +++++
 test/unit/modules/vdom/create-element.spec.ts | 43 +++++++++++++++++++
 2 files changed, 54 insertions(+)

diff --git a/src/core/vdom/create-element.ts b/src/core/vdom/create-element.ts
index 62dd004c34a..bad54d97fa0 100644
--- a/src/core/vdom/create-element.ts
+++ b/src/core/vdom/create-element.ts
@@ -157,6 +157,17 @@ function applyNS(vnode, ns, force?: boolean) {
       }
     }
   }
+
+  // #11315
+  if (isObject(vnode.componentOptions) && isDef(vnode.componentOptions.children)) {
+    for (var i = 0, l = vnode.componentOptions.children.length; i < l; i++) {
+      var child = vnode.componentOptions.children[i]
+      if (isDef(child.tag) && (
+        isUndef(child.ns) || (isTrue(force) && child.tag !== 'svg'))) {
+        applyNS(child, ns, force)
+      }
+    }
+  }
 }
 
 // ref #5318
diff --git a/test/unit/modules/vdom/create-element.spec.ts b/test/unit/modules/vdom/create-element.spec.ts
index f97b4bc07cf..7ba8730c42c 100644
--- a/test/unit/modules/vdom/create-element.spec.ts
+++ b/test/unit/modules/vdom/create-element.spec.ts
@@ -147,6 +147,49 @@ describe('create-element', () => {
     expect(vnode.children[0].children[1].ns).toBe('svg')
   })
 
+  // #11315
+  it('render svg foreignObject nested component slot with correct namespace', () => {
+    const vm = new Vue({
+      template: `
+        <svg>
+          <box></box>
+        </svg>
+      `,
+      components: {
+        'box': {
+          template: `
+            <foreignObject>
+              <comp-with-slot>
+                <p></p><svg></svg>
+              </comp-with-slot>
+            </foreignObject>
+          `,
+          components: {
+            'comp-with-slot': {
+              template: `
+                <div>
+                  <slot />
+                </div>
+              `
+            }
+          }
+        }
+      }
+    }).$mount()
+    const box = vm.$children[0]
+    const compWithSlot = box.$children[0]
+    expect(box.$vnode.ns).toBe('svg')
+    expect(box._vnode.tag).toBe('foreignObject')
+    expect(box._vnode.ns).toBe('svg')
+    expect(compWithSlot.$vnode.ns).toBeUndefined()
+    expect(compWithSlot._vnode.tag).toBe('div')
+    expect(compWithSlot._vnode.ns).toBeUndefined()
+    expect(compWithSlot._vnode.children[0].tag).toBe('p')
+    expect(compWithSlot._vnode.children[0].ns).toBeUndefined()
+    expect(compWithSlot._vnode.children[1].tag).toBe('svg')
+    expect(compWithSlot._vnode.children[1].ns).toBe('svg')
+  })
+
   // #6642
   it('render svg foreignObject component with correct namespace', () => {
     const vm = new Vue({

From 446b2ce9ec5ebff3bb03d59c66c6c154c79339a3 Mon Sep 17 00:00:00 2001
From: Rairn <958414905@qq.com>
Date: Mon, 2 Jan 2023 15:34:24 +0800
Subject: [PATCH 2/2] refactor: extract variable

---
 src/core/vdom/create-element.ts | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/core/vdom/create-element.ts b/src/core/vdom/create-element.ts
index bad54d97fa0..6abade56757 100644
--- a/src/core/vdom/create-element.ts
+++ b/src/core/vdom/create-element.ts
@@ -146,9 +146,14 @@ function applyNS(vnode, ns, force?: boolean) {
     ns = undefined
     force = true
   }
-  if (isDef(vnode.children)) {
-    for (let i = 0, l = vnode.children.length; i < l; i++) {
-      const child = vnode.children[i]
+  const children =
+    vnode.children ||
+    // #11315
+    (vnode.componentOptions && vnode.componentOptions.children)
+
+  if (isDef(children)) {
+    for (let i = 0, l = children.length; i < l; i++) {
+      const child = children[i]
       if (
         isDef(child.tag) &&
         (isUndef(child.ns) || (isTrue(force) && child.tag !== 'svg'))
@@ -157,17 +162,6 @@ function applyNS(vnode, ns, force?: boolean) {
       }
     }
   }
-
-  // #11315
-  if (isObject(vnode.componentOptions) && isDef(vnode.componentOptions.children)) {
-    for (var i = 0, l = vnode.componentOptions.children.length; i < l; i++) {
-      var child = vnode.componentOptions.children[i]
-      if (isDef(child.tag) && (
-        isUndef(child.ns) || (isTrue(force) && child.tag !== 'svg'))) {
-        applyNS(child, ns, force)
-      }
-    }
-  }
 }
 
 // ref #5318