fix: bail stringification for slots

fix #1281, close #1286

packages/compiler-dom/__tests__/transforms/stringifyStatic.spec.ts

@@ -250,7 +250,7 @@ describe('stringify static html', () => {
     })
   })
 
-  test('should bail on break content with innerHTML (eg.tables related tags)', () => {
+  test('should bail on tags that has placement constraints (eg.tables related tags)', () => {
     const { ast } = compileWithStringify(
       `<table><tbody>${repeat(
         `<tr class="foo"><td>foo</td></tr>`,
@@ -262,4 +262,36 @@ describe('stringify static html', () => {
       type: NodeTypes.VNODE_CALL // not CALL_EXPRESSION
     })
   })
+
+  test('should bail inside slots', () => {
+    const { ast } = compileWithStringify(
+      `<foo>${repeat(
+        `<div class="foo"></div>`,
+        StringifyThresholds.ELEMENT_WITH_BINDING_COUNT
+      )}</foo>`
+    )
+    expect(ast.hoists.length).toBe(
+      StringifyThresholds.ELEMENT_WITH_BINDING_COUNT
+    )
+    ast.hoists.forEach(node => {
+      expect(node).toMatchObject({
+        type: NodeTypes.VNODE_CALL // not CALL_EXPRESSION
+      })
+    })
+
+    const { ast: ast2 } = compileWithStringify(
+      `<foo><template #foo>${repeat(
+        `<div class="foo"></div>`,
+        StringifyThresholds.ELEMENT_WITH_BINDING_COUNT
+      )}</template></foo>`
+    )
+    expect(ast2.hoists.length).toBe(
+      StringifyThresholds.ELEMENT_WITH_BINDING_COUNT
+    )
+    ast2.hoists.forEach(node => {
+      expect(node).toMatchObject({
+        type: NodeTypes.VNODE_CALL // not CALL_EXPRESSION
+      })
+    })
+  })
 })

packages/compiler-dom/src/transforms/stringifyStatic.ts

@@ -59,7 +59,15 @@ type StringifiableNode = PlainElementNode | TextCallNode
  *
  * This optimization is only performed in Node.js.
  */
-export const stringifyStatic: HoistTransform = (children, context) => {
+export const stringifyStatic: HoistTransform = (children, context, parent) => {
+  if (
+    parent.type === NodeTypes.ELEMENT &&
+    (parent.tagType === ElementTypes.COMPONENT ||
+      parent.tagType === ElementTypes.TEMPLATE)
+  ) {
+    return
+  }
+
   let nc = 0 // current node count
   let ec = 0 // current element with binding count
   const currentChunk: StringifiableNode[] = []