Function handler

packages/browser/src/node/plugin.ts:402–416

(code, id)

          code: /import\.meta\.vitest/,
        },
        handler(code, id) {
          const filename = cleanUrl(id)

          if (!code.includes('import.meta.vitest')) {
            return
          }
          const s = new MagicString(code, { filename })
          s.prepend(
            `Object.defineProperty(import.meta, 'vitest', { get() { return typeof __vitest_worker__ !== 'undefined' && __vitest_worker__.filepath === "${filename.replace(/"/g, '\\"')}" ? __vitest_index__ : undefined } });\n`,
          )
          return {
            code: s.toString(),
            map: s.generateMap({ hires: true }),
          }
        },
      },
    },
    {