fix(compiler-core): comments in the <pre> tag should be removed in production mode

packages/compiler-core/src/parse.ts

@@ -246,6 +246,15 @@ function parseChildren(
       if (first && first.type === NodeTypes.TEXT) {
         first.content = first.content.replace(/^\r?\n/, '')
       }
+      if (!__DEV__ && !context.options.comments) {
+        for (let i = 0; i < nodes.length; i++) {
+          const node = nodes[i]
+          if (node.type === NodeTypes.COMMENT) {
+            removedWhitespace = true
+            nodes[i] = null as any
+          }
+        }
+      }
     }
   }
 

packages/compiler-core/src/transforms/transformText.ts

@@ -9,6 +9,7 @@ import {
 import { isText } from '../utils'
 import { CREATE_TEXT } from '../runtimeHelpers'
 import { PatchFlags, PatchFlagNames } from '@vue/shared'
+import { getStaticType } from './hoistStatic'
 
 // Merge adjacent text nodes and expressions into a single expression
 // e.g. <div>abc {{ d }} {{ e }}</div> should have a single expression node as child.
@@ -78,7 +79,7 @@ export const transformText: NodeTransform = (node, context) => {
             callArgs.push(child)
           }
           // mark dynamic text with flag so it gets patched inside a block
-          if (!context.ssr && child.type !== NodeTypes.TEXT) {
+          if (!context.ssr && !getStaticType(child)) {
             callArgs.push(
               `${PatchFlags.TEXT} /* ${PatchFlagNames[PatchFlags.TEXT]} */`
             )

packages/compiler-dom/__tests__/parse.spec.ts

@@ -159,6 +159,25 @@ describe('DOM parser', () => {
       ])
     })
 
+    // #2217
+    test('comments in the <pre> tag should be removed in production mode', () => {
+      __DEV__ = false
+      const rawText = `<p/><!-- foo --><p/>`
+      const ast = parse(`<pre>${rawText}</pre>`, parserOptions)
+      __DEV__ = true
+
+      expect((ast.children[0] as ElementNode).children).toMatchObject([
+        {
+          type: NodeTypes.ELEMENT,
+          tag: 'p'
+        },
+        {
+          type: NodeTypes.ELEMENT,
+          tag: 'p'
+        }
+      ])
+    })
+
     // #945
     test('&nbsp; should not be condensed', () => {
       const nbsp = String.fromCharCode(160)