How to use the @vuepress/shared-utils.fs.writeFile function in @vuepress/shared-utils

async function workaroundEmptyStyleChunk () {
    const styleChunk = stats.children[0].assets.find(a => {
      return /styles\.\w{8}\.js$/.test(a.name)
    })
    if (!styleChunk) return
    const styleChunkPath = path.resolve(outDir, styleChunk.name)
    const styleChunkContent = await fs.readFile(styleChunkPath, 'utf-8')
    await fs.remove(styleChunkPath)
    // prepend it to app.js.
    // this is necessary for the webpack runtime to work properly.
    const appChunk = stats.children[0].assets.find(a => {
      return /app\.\w{8}\.js$/.test(a.name)
    })
    const appChunkPath = path.resolve(outDir, appChunk.name)
    const appChunkContent = await fs.readFile(appChunkPath, 'utf-8')
    await fs.writeFile(appChunkPath, styleChunkContent + appChunkContent)
  }
}

async function workaroundEmptyStyleChunk (stats, outDir) {
  const styleChunk = stats.children[0].assets.find(a => {
    return /styles\.\w{8}\.js$/.test(a.name)
  })
  if (!styleChunk) return
  const styleChunkPath = path.resolve(outDir, styleChunk.name)
  const styleChunkContent = await fs.readFile(styleChunkPath, 'utf-8')
  await fs.remove(styleChunkPath)
  // prepend it to app.js.
  // this is necessary for the webpack runtime to work properly.
  const appChunk = stats.children[0].assets.find(a => {
    return /app\.\w{8}\.js$/.test(a.name)
  })
  const appChunkPath = path.resolve(outDir, appChunk.name)
  const appChunkContent = await fs.readFile(appChunkPath, 'utf-8')
  await fs.writeFile(appChunkPath, styleChunkContent + appChunkContent)
}

async function workaroundEmptyStyleChunk () {
    const styleChunk = stats.children[0].assets.find(a => {
      return /styles\.\w{8}\.js$/.test(a.name)
    })
    if (!styleChunk) return
    const styleChunkPath = path.resolve(outDir, styleChunk.name)
    const styleChunkContent = await fs.readFile(styleChunkPath, 'utf-8')
    await fs.remove(styleChunkPath)
    // prepend it to app.js.
    // this is necessary for the webpack runtime to work properly.
    const appChunk = stats.children[0].assets.find(a => {
      return /app\.\w{8}\.js$/.test(a.name)
    })
    const appChunkPath = path.resolve(outDir, appChunk.name)
    const appChunkContent = await fs.readFile(appChunkPath, 'utf-8')
    await fs.writeFile(appChunkPath, styleChunkContent + appChunkContent)
  }
}

async generated () {
    const { serviceWorker } = options
    const { outDir } = context
    const swFilePath = path.resolve(outDir, 'service-worker.js')
    if (serviceWorker) {
      logger.wait('Generating service worker...')
      const wbb = require('workbox-build')
      await wbb.generateSW({
        swDest: swFilePath,
        globDirectory: outDir,
        globPatterns: ['**\/*.{js,css,html,png,jpg,jpeg,gif,svg,woff,woff2,eot,ttf,otf}'],
        ...(options.generateSWConfig || {})
      })
      await fs.writeFile(
        swFilePath,
        await fs.readFile(path.resolve(__dirname, 'lib/skip-waiting.js'), 'utf8'),
        { flag: 'a' }
      )
    }
  }
})

title: 'VuePress',
      lang: 'en',
      description: ''
    }

    let html
    try {
      html = await this.renderer.renderToString(context)
    } catch (e) {
      console.error(logger.error(chalk.red(`Error rendering ${pagePath}:`), false))
      throw e
    }
    const filename = pagePath.replace(/\/$/, '/index.html').replace(/^\//, '')
    const filePath = path.resolve(this.outDir, filename)
    await fs.ensureDir(path.dirname(filePath))
    await fs.writeFile(filePath, html)
    return filePath
  }
}

title: 'VuePress',
      lang: 'en',
      description: ''
    }

    let html
    try {
      html = await renderer.renderToString(context)
    } catch (e) {
      console.error(logger.error(chalk.red(`Error rendering ${pagePath}:`), false))
      throw e
    }
    const filename = decodeURIComponent(pagePath.replace(/\/$/, '/index.html').replace(/^\//, ''))
    const filePath = path.resolve(outDir, filename)
    await fs.ensureDir(path.dirname(filePath))
    await fs.writeFile(filePath, html)
  }

title: 'VuePress',
      lang: 'en',
      description: ''
    }

    let html
    try {
      html = await renderer.renderToString(context)
    } catch (e) {
      console.error(logger.error(chalk.red(`Error rendering ${pagePath}:`), false))
      throw e
    }
    const filename = decodeURIComponent(pagePath.replace(/\/$/, '/index.html').replace(/^\//, ''))
    const filePath = path.resolve(outDir, filename)
    await fs.ensureDir(path.dirname(filePath))
    await fs.writeFile(filePath, html)
    return filePath
  }