Function generateBundle

packages/vite/src/node/plugins/html.ts:824–1081

(options, bundle)

    },

    async generateBundle(options, bundle) {
      const analyzedImportedCssFiles = new Map<OutputChunk, string[]>()
      const inlineEntryChunk = new Set<string>()
      const getImportedChunks = (
        chunk: OutputChunk,
        seen: Set<string> = new Set(),
      ): (OutputChunk | string)[] => {
        const chunks: (OutputChunk | string)[] = []
        chunk.imports.forEach((file) => {
          const importee = bundle[file]
          if (importee) {
            if (importee.type === 'chunk' && !seen.has(file)) {
              seen.add(file)

              // post-order traversal
              chunks.push(...getImportedChunks(importee, seen))
              chunks.push(importee)
            }
          } else {
            // external imports
            chunks.push(file)
          }
        })
        return chunks
      }

      const toScriptTag = (
        chunkOrUrl: OutputChunk | string,
        toOutputPath: (filename: string) => string,
        isAsync: boolean,
      ): HtmlTagDescriptor => ({
        tag: 'script',
        attrs: {
          ...(isAsync ? { async: true } : {}),
          type: 'module',
          // crossorigin must be set not only for serving assets in a different origin
          // but also to make it possible to preload the script using `<link rel="preload">`.
          // `<script type="module">` used to fetch the script with credential mode `omit`,
          // however `crossorigin` attribute cannot specify that value.
          // https://developer.chrome.com/blog/modulepreload/#ok-so-why-doesnt-link-relpreload-work-for-modules:~:text=For%20%3Cscript%3E,of%20other%20modules.
          // Now `<script type="module">` uses `same origin`: https://github.com/whatwg/html/pull/3656#:~:text=Module%20scripts%20are%20always%20fetched%20with%20credentials%20mode%20%22same%2Dorigin%22%20by%20default%20and%20can%20no%20longer%0Ause%20%22omit%22
          crossorigin: true,
          src:
            typeof chunkOrUrl === 'string'
              ? chunkOrUrl
              : toOutputPath(chunkOrUrl.fileName),
        },
      })

      const toPreloadTag = (
        filename: string,
        toOutputPath: (filename: string) => string,
      ): HtmlTagDescriptor => ({
        tag: 'link',
        attrs: {
          rel: 'modulepreload',
          crossorigin: true,
          href: toOutputPath(filename),