fix(build): show dead link line numbers (#5230)

__tests__/unit/node/markdown/plugins/link.test.ts

@@ -48,4 +48,17 @@ describe('node/markdown/plugins/link', () => {
       'href="/foo.html?title=Cat&oldid=916388819#:~:text=Claws-,Like%20almost,the%20Felidae%2C,-cats"'
     )
   })
+
+  test('records source line numbers for collected links', async () => {
+    const env: {
+      cleanUrls: boolean
+      links?: string[]
+      linkLines?: number[]
+    } = { cleanUrls: false }
+
+    await md.renderAsync('Intro\n\n[Missing](./missing.md)\n', env)
+
+    expect(env.links).toEqual(['./missing'])
+    expect(env.linkLines).toEqual([3])
+  })
 })

__tests__/unit/node/markdownToVue.test.ts

@@ -0,0 +1,69 @@
+import { mkdtemp, rm, writeFile } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import path from 'node:path'
+import { resolveConfig } from 'node/config'
+import { createMarkdownToVueRenderFn } from 'node/markdownToVue'
+
+describe('node/markdownToVue', () => {
+  let root: string | undefined
+
+  afterEach(async () => {
+    if (root) {
+      await rm(root, { recursive: true, force: true })
+      root = undefined
+    }
+  })
+
+  test('records source line numbers for dead links', async () => {
+    root = await mkdtemp(path.join(tmpdir(), 'vitepress-dead-link-'))
+
+    const file = path.join(root, 'index.md')
+    const src = '# Home\n\nIntro\n\n[Missing](./missing.md)\n'
+    await writeFile(file, src)
+
+    const siteConfig = await resolveConfig(root, 'build', 'production')
+    const render = await createMarkdownToVueRenderFn(
+      siteConfig.srcDir,
+      { cache: false },
+      '/',
+      false,
+      false,
+      siteConfig
+    )
+
+    const result = await render(src, file, 'public')
+
+    expect(result.deadLinks).toContainEqual({
+      url: './missing',
+      file,
+      line: 5
+    })
+  })
+
+  test('records source line numbers after frontmatter', async () => {
+    root = await mkdtemp(path.join(tmpdir(), 'vitepress-dead-link-'))
+
+    const file = path.join(root, 'index.md')
+    const src =
+      '---\ntitle: Home\n---\n# Home\n\nIntro\n\n[Missing](./missing.md)\n'
+    await writeFile(file, src)
+
+    const siteConfig = await resolveConfig(root, 'build', 'production')
+    const render = await createMarkdownToVueRenderFn(
+      siteConfig.srcDir,
+      { cache: false },
+      '/',
+      false,
+      false,
+      siteConfig
+    )
+
+    const result = await render(src, file, 'public')
+
+    expect(result.deadLinks).toContainEqual({
+      url: './missing',
+      file,
+      line: 8
+    })
+  })
+})

src/node/markdown/plugins/link.ts

@@ -19,6 +19,20 @@ export const linkPlugin = (
   base: string,
   slugify: (str: string) => string
 ) => {
+  md.core.ruler.after('inline', 'vitepress_link_lines', (state) => {
+    for (const token of state.tokens) {
+      if (token.type !== 'inline' || !token.children || !token.map) continue
+
+      const line = token.map[0] + 1
+      for (const child of token.children) {
+        if (child.type === 'link_open') {
+          child.meta ??= {}
+          child.meta.vpLine = line
+        }
+      }
+    }
+  })
+
   md.renderer.rules.link_open = (
     tokens,
     idx,
@@ -41,7 +55,7 @@ export const linkPlugin = (
         })
         // catch localhost links as dead link
         if (url.replace(EXTERNAL_URL_RE, '').startsWith('//localhost:')) {
-          pushLink(url, env)
+          pushLink(url, env, token.meta?.vpLine)
         }
         hrefAttr[1] = url
       } else {
@@ -58,7 +72,7 @@ export const linkPlugin = (
           // skip links to files (other than html/md)
           treatAsHtml(pathname)
         ) {
-          normalizeHref(hrefAttr, env)
+          normalizeHref(hrefAttr, env, token.meta?.vpLine)
         } else if (url.startsWith('#')) {
           hrefAttr[1] = decodeURI(normalizeHash(hrefAttr[1]))
         }
@@ -75,7 +89,11 @@ export const linkPlugin = (
     return self.renderToken(tokens, idx, options)
   }
 
-  function normalizeHref(hrefAttr: [string, string], env: MarkdownEnv) {
+  function normalizeHref(
+    hrefAttr: [string, string],
+    env: MarkdownEnv,
+    line?: number
+  ) {
     let url = hrefAttr[1]
 
     const indexMatch = url.match(indexRE)
@@ -106,7 +124,7 @@ export const linkPlugin = (
     }
 
     // export it for existence check
-    pushLink(url.replace(/\.html$/, ''), env)
+    pushLink(url.replace(/\.html$/, ''), env, line)
 
     // markdown-it encodes the uri
     hrefAttr[1] = decodeURI(url)
@@ -116,8 +134,12 @@ export const linkPlugin = (
     return str ? encodeURI('#' + slugify(decodeURI(str).slice(1))) : ''
   }
 
-  function pushLink(link: string, env: MarkdownEnv) {
+  function pushLink(link: string, env: MarkdownEnv, line?: number) {
     const links = env.links || (env.links = [])
     links.push(link)
+    if (line != null) {
+      const linkLines = env.linkLines || (env.linkLines = [])
+      linkLines[links.length - 1] = line
+    }
   }
 }

src/node/markdownToVue.ts

@@ -28,7 +28,7 @@ const cache = new LRUCache<string, MarkdownCompileResult>({ max: 1024 })
 export interface MarkdownCompileResult {
   vueSrc: string
   pageData: PageData
-  deadLinks: { url: string; file: string }[]
+  deadLinks: { url: string; file: string; line?: number }[]
   includes: string[]
 }
 
@@ -151,17 +151,24 @@ export async function createMarkdownToVueRenderFn(
     }
     const html = await md.renderAsync(src, env)
     const {
+      content,
       frontmatter = {},
       headers = [],
+      linkLines = [],
       links = [],
       sfcBlocks,
       title = ''
     } = env
+    const contentLineOffset = countLineBreaks(
+      content && src.endsWith(content) ? src.slice(0, -content.length) : ''
+    )
 
     // validate data.links
     const deadLinks: MarkdownCompileResult['deadLinks'] = []
-    const recordDeadLink = (url: string) => {
+    const recordDeadLink = (url: string, line?: number) => {
-      deadLinks.push({ url, file: fileOrig })
+      deadLinks.push(
+        line == null ? { url, file: fileOrig } : { url, file: fileOrig, line }
+      )
     }
 
     function shouldIgnoreDeadLink(url: string) {
@@ -185,7 +192,12 @@ export async function createMarkdownToVueRenderFn(
 
     if (links && siteConfig?.ignoreDeadLinks !== true) {
       const dir = path.dirname(file)
-      for (let url of links) {
+      for (const [index, rawUrl] of links.entries()) {
+        let url = rawUrl
+        const line =
+          linkLines[index] == null
+            ? undefined
+            : linkLines[index] + contentLineOffset
         const { pathname } = new URL(url, 'http://a.com')
         if (!treatAsHtml(pathname)) continue
 
@@ -207,7 +219,7 @@ export async function createMarkdownToVueRenderFn(
           !fs.existsSync(path.resolve(dir, publicDir, `${resolved}.html`)) &&
           !shouldIgnoreDeadLink(url)
         ) {
-          recordDeadLink(url)
+          recordDeadLink(url, line)
         }
       }
     }
@@ -332,6 +344,10 @@ const inferDescription = (frontmatter: Record<string, any>) => {
   return (head && getHeadMetaContent(head, 'description')) || ''
 }
 
+function countLineBreaks(str: string) {
+  return str.match(/\r?\n/g)?.length ?? 0
+}
+
 const getHeadMetaContent = (head: HeadConfig[], name: string) => {
   if (!head || !head.length) {
     return undefined

src/node/plugin.ts

@@ -422,14 +422,15 @@ function logDeadLinks(
   devMode = false
 ) {
   const logged = new Set<string>()
-  deadLinks.forEach(({ url, file }, i) => {
+  deadLinks.forEach(({ url, file, line }, i) => {
-    const key = `${file}:::${url}`
+    const location = line == null ? file : `${file}:${line}`
+    const key = `${location}:::${url}`
     if (logged.has(key)) return
     logged.add(key)
     const prefix = '\n'.repeat(i === 0 ? (devMode ? 1 : 2) : 0)
     logger.warn(
       c.yellow(
-        `${prefix}(!) Found dead link ${c.cyan(url)} in file ${c.white(c.dim(file))}`
+        `${prefix}(!) Found dead link ${c.cyan(url)} in file ${c.white(c.dim(location))}`
       )
     )
   })

types/shared.d.ts

@@ -223,6 +223,7 @@ export interface MarkdownEnv {
   relativePath: string
   cleanUrls: boolean
   links?: string[]
+  linkLines?: number[]
   includes?: string[]
   realPath?: string
   localeIndex?: string