fix(compiler-dom): improve HTML nesting validation to allow any child element within template tag (vuejs#13320)

close vuejs#13318

Author: edison1105

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

@@ -1,4 +1,5 @@
 import { type CompilerError, compile } from '../../src'
+import { isValidHTMLNesting } from '../../src/htmlNesting'
 
 describe('validate html nesting', () => {
   it('should warn with p > div', () => {
@@ -17,4 +18,185 @@ describe('validate html nesting', () => {
     })
     expect(err).toBeUndefined()
   })
+
+  // #13318
+  it('should not warn when parent tag is template', () => {
+    let err: CompilerError | undefined
+    compile(`<template><tr/></template>`, {
+      onWarn: e => (err = e),
+    })
+    expect(err).toBeUndefined()
+  })
+})
+
+/**
+ * Copied from https://github.com/MananTank/validate-html-nesting
+ * with ISC license
+ */
+describe('isValidHTMLNesting', () => {
+  test('form', () => {
+    // invalid
+    expect(isValidHTMLNesting('form', 'form')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('form', 'div')).toBe(true)
+    expect(isValidHTMLNesting('form', 'input')).toBe(true)
+    expect(isValidHTMLNesting('form', 'select')).toBe(true)
+    expect(isValidHTMLNesting('form', 'button')).toBe(true)
+    expect(isValidHTMLNesting('form', 'label')).toBe(true)
+    expect(isValidHTMLNesting('form', 'h1')).toBe(true)
+  })
+
+  test('p', () => {
+    // invalid
+    expect(isValidHTMLNesting('p', 'p')).toBe(false)
+    expect(isValidHTMLNesting('p', 'div')).toBe(false)
+    expect(isValidHTMLNesting('p', 'hr')).toBe(false)
+    expect(isValidHTMLNesting('p', 'blockquote')).toBe(false)
+    expect(isValidHTMLNesting('p', 'pre')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('p', 'a')).toBe(true)
+    expect(isValidHTMLNesting('p', 'span')).toBe(true)
+    expect(isValidHTMLNesting('p', 'abbr')).toBe(true)
+    expect(isValidHTMLNesting('p', 'button')).toBe(true)
+    expect(isValidHTMLNesting('p', 'b')).toBe(true)
+    expect(isValidHTMLNesting('p', 'i')).toBe(true)
+    expect(isValidHTMLNesting('p', 'input')).toBe(true)
+    expect(isValidHTMLNesting('p', 'label')).toBe(true)
+  })
+
+  test('a', () => {
+    // invalid
+    expect(isValidHTMLNesting('a', 'a')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('a', 'div')).toBe(true)
+    expect(isValidHTMLNesting('a', 'span')).toBe(true)
+  })
+
+  test('button', () => {
+    // invalid
+    expect(isValidHTMLNesting('button', 'button')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('button', 'div')).toBe(true)
+    expect(isValidHTMLNesting('button', 'span')).toBe(true)
+  })
+
+  test('table', () => {
+    // invalid
+    expect(isValidHTMLNesting('table', 'tr')).toBe(false)
+    expect(isValidHTMLNesting('table', 'table')).toBe(false)
+    expect(isValidHTMLNesting('table', 'td')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('table', 'thead')).toBe(true)
+    expect(isValidHTMLNesting('table', 'tbody')).toBe(true)
+    expect(isValidHTMLNesting('table', 'tfoot')).toBe(true)
+    expect(isValidHTMLNesting('table', 'caption')).toBe(true)
+    expect(isValidHTMLNesting('table', 'colgroup')).toBe(true)
+  })
+
+  test('td', () => {
+    // valid
+    expect(isValidHTMLNesting('td', 'span')).toBe(true)
+    expect(isValidHTMLNesting('tr', 'td')).toBe(true)
+
+    // invalid
+    expect(isValidHTMLNesting('td', 'td')).toBe(false)
+    expect(isValidHTMLNesting('div', 'td')).toBe(false)
+  })
+
+  test('tbody', () => {
+    // invalid
+    expect(isValidHTMLNesting('tbody', 'td')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('tbody', 'tr')).toBe(true)
+  })
+
+  test('tr', () => {
+    // invalid
+    expect(isValidHTMLNesting('tr', 'tr')).toBe(false)
+    expect(isValidHTMLNesting('table', 'tr')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('tbody', 'tr')).toBe(true)
+    expect(isValidHTMLNesting('thead', 'tr')).toBe(true)
+    expect(isValidHTMLNesting('tfoot', 'tr')).toBe(true)
+    expect(isValidHTMLNesting('tr', 'td')).toBe(true)
+    expect(isValidHTMLNesting('tr', 'th')).toBe(true)
+  })
+
+  test('li', () => {
+    // invalid
+    expect(isValidHTMLNesting('li', 'li')).toBe(false)
+    // valid
+    expect(isValidHTMLNesting('li', 'div')).toBe(true)
+    expect(isValidHTMLNesting('li', 'ul')).toBe(true)
+  })
+
+  test('headings', () => {
+    // invalid
+    expect(isValidHTMLNesting('h1', 'h1')).toBe(false)
+    expect(isValidHTMLNesting('h2', 'h1')).toBe(false)
+    expect(isValidHTMLNesting('h3', 'h1')).toBe(false)
+    expect(isValidHTMLNesting('h1', 'h6')).toBe(false)
+
+    // valid
+    expect(isValidHTMLNesting('h1', 'div')).toBe(true)
+  })
+
+  describe('SVG', () => {
+    test('svg', () => {
+      // invalid non-svg tags as children
+      expect(isValidHTMLNesting('svg', 'div')).toBe(false)
+      expect(isValidHTMLNesting('svg', 'img')).toBe(false)
+      expect(isValidHTMLNesting('svg', 'p')).toBe(false)
+      expect(isValidHTMLNesting('svg', 'h2')).toBe(false)
+      expect(isValidHTMLNesting('svg', 'span')).toBe(false)
+
+      // valid non-svg tags as children
+      expect(isValidHTMLNesting('svg', 'a')).toBe(true)
+      expect(isValidHTMLNesting('svg', 'textarea')).toBe(true)
+      expect(isValidHTMLNesting('svg', 'input')).toBe(true)
+      expect(isValidHTMLNesting('svg', 'select')).toBe(true)
+
+      // valid svg tags as children
+      expect(isValidHTMLNesting('svg', 'g')).toBe(true)
+      expect(isValidHTMLNesting('svg', 'ellipse')).toBe(true)
+      expect(isValidHTMLNesting('svg', 'feOffset')).toBe(true)
+    })
+
+    test('foreignObject', () => {
+      // valid
+      expect(isValidHTMLNesting('foreignObject', 'g')).toBe(true)
+      expect(isValidHTMLNesting('foreignObject', 'div')).toBe(true)
+      expect(isValidHTMLNesting('foreignObject', 'a')).toBe(true)
+      expect(isValidHTMLNesting('foreignObject', 'textarea')).toBe(true)
+    })
+
+    test('g', () => {
+      // valid
+      expect(isValidHTMLNesting('g', 'div')).toBe(true)
+      expect(isValidHTMLNesting('g', 'p')).toBe(true)
+      expect(isValidHTMLNesting('g', 'a')).toBe(true)
+      expect(isValidHTMLNesting('g', 'textarea')).toBe(true)
+      expect(isValidHTMLNesting('g', 'g')).toBe(true)
+    })
+
+    test('dl', () => {
+      // valid
+      expect(isValidHTMLNesting('dl', 'dt')).toBe(true)
+      expect(isValidHTMLNesting('dl', 'dd')).toBe(true)
+      expect(isValidHTMLNesting('dl', 'div')).toBe(true)
+      expect(isValidHTMLNesting('div', 'dt')).toBe(true)
+      expect(isValidHTMLNesting('div', 'dd')).toBe(true)
+
+      // invalid
+      expect(isValidHTMLNesting('span', 'dt')).toBe(false)
+      expect(isValidHTMLNesting('span', 'dd')).toBe(false)
+    })
+  })
 })

packages/compiler-dom/src/htmlNesting.ts

@@ -11,6 +11,11 @@
  * returns true if given parent-child nesting is valid HTML
  */
 export function isValidHTMLNesting(parent: string, child: string): boolean {
+  // if the parent is a template, it can have any child
+  if (parent === 'template') {
+    return true
+  }
+
   // if we know the list of children that are the only valid children for the given parent
   if (parent in onlyValidChildren) {
     return onlyValidChildren[parent].has(child)