Function buildHtmlPlugin

packages/vite/src/node/plugins/html.ts:413–1083

(config: ResolvedConfig)

 * Compiles index.html into an entry js module
 */
export function buildHtmlPlugin(config: ResolvedConfig): Plugin {
  const [preHooks, normalHooks, postHooks] = resolveHtmlTransforms(
    config.plugins,
  )
  preHooks.unshift(injectCspNonceMetaTagHook(config))
  preHooks.unshift(preImportMapHook(config))
  preHooks.push(htmlEnvHook(config))
  postHooks.push(injectNonceAttributeTagHook(config))
  postHooks.push(postImportMapHook(config))
  const processedHtml = perEnvironmentState(() => new Map<string, string>())

  const isExcludedUrl = (url: string) =>
    url[0] === '#' || isExternalUrl(url) || isDataUrl(url)

  // Same reason with `htmlInlineProxyPlugin`
  isAsyncScriptMap.set(config, new Map())

  return {
    name: 'vite:build-html',

    applyToEnvironment(environment) {
      return environment.config.isBundled
    },

    transform: {
      filter: { id: /\.html$/ },
      async handler(html, id) {
        id = normalizePath(id)
        const relativeUrlPath = normalizePath(path.relative(config.root, id))
        const publicPath = `/${relativeUrlPath}`
        const publicBase = getBaseInHTML(relativeUrlPath, config)

        const publicToRelative = (filename: string) => publicBase + filename
        const toOutputPublicFilePath = (url: string) =>
          toOutputFilePathInHtml(
            url.slice(1),
            'public',
            relativeUrlPath,
            'html',
            config,
            publicToRelative,
          )
        // Determines true start position for the node, either the < character
        // position, or the newline at the end of the previous line's node.
        const nodeStartWithLeadingWhitespace = (
          node: DefaultTreeAdapterMap['node'],
        ) => {
          const startOffset = node.sourceCodeLocation!.startOffset
          if (startOffset === 0) return 0

          // Gets the offset for the start of the line including the
          // newline trailing the previous node
          const lineStartOffset =
            startOffset - node.sourceCodeLocation!.startCol

          // <previous-line-node></previous-line-node>
          // <target-node></target-node>
          //