From a096a58e412dc37ae618a3b4702f591c580d376a Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Mon, 14 Sep 2020 12:41:35 -0400
Subject: [PATCH] fix(compiler-core): fix v-if block handling for components
 that fail to resolve

fix #2058
---
 .../compiler-core/__tests__/transforms/vIf.spec.ts   |  4 +++-
 packages/compiler-core/src/transforms/vIf.ts         | 12 ++----------
 2 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/packages/compiler-core/__tests__/transforms/vIf.spec.ts b/packages/compiler-core/__tests__/transforms/vIf.spec.ts
index a93c6053..315497a5 100644
--- a/packages/compiler-core/__tests__/transforms/vIf.spec.ts
+++ b/packages/compiler-core/__tests__/transforms/vIf.spec.ts
@@ -93,10 +93,12 @@ describe('compiler: v-if', () => {
       expect((node.branches[0].children[0] as ElementNode).tagType).toBe(
         ElementTypes.COMPONENT
       )
+      // #2058 since a component may fail to resolve and fallback to a plain
+      // element, it still needs to be made a block
       expect(
         ((node.branches[0].children[0] as ElementNode)!
           .codegenNode as VNodeCall)!.isBlock
-      ).toBe(false)
+      ).toBe(true)
     })
 
     test('v-if + v-else', () => {
diff --git a/packages/compiler-core/src/transforms/vIf.ts b/packages/compiler-core/src/transforms/vIf.ts
index bebf3eb9..2c003492 100644
--- a/packages/compiler-core/src/transforms/vIf.ts
+++ b/packages/compiler-core/src/transforms/vIf.ts
@@ -29,8 +29,7 @@ import {
   CREATE_BLOCK,
   FRAGMENT,
   CREATE_COMMENT,
-  OPEN_BLOCK,
-  TELEPORT
+  OPEN_BLOCK
 } from '../runtimeHelpers'
 import { injectProp, findDir, findProp } from '../utils'
 import { PatchFlags, PatchFlagNames } from '@vue/shared'
@@ -255,14 +254,7 @@ function createChildrenCodegenNode(
     const vnodeCall = (firstChild as ElementNode)
       .codegenNode as BlockCodegenNode
     // Change createVNode to createBlock.
-    if (
-      vnodeCall.type === NodeTypes.VNODE_CALL &&
-      // component vnodes are always tracked and its children are
-      // compiled into slots so no need to make it a block
-      ((firstChild as ElementNode).tagType !== ElementTypes.COMPONENT ||
-        // teleport has component type but isn't always tracked
-        vnodeCall.tag === TELEPORT)
-    ) {
+    if (vnodeCall.type === NodeTypes.VNODE_CALL) {
       vnodeCall.isBlock = true
       helper(OPEN_BLOCK)
       helper(CREATE_BLOCK)