如何在`dev`中调试`vite-plugin-static-copy`转换函数？

我刚刚从 webpack 转移过来copyWebpackPlugin，并且无法理解如何调试这个插件的代码。

这是我的vite.config.ts

import { defineConfig } from 'vite';
import preact from '@preact/preset-vite';
import ssr from 'vike/plugin';
import { viteStaticCopy } from 'vite-plugin-static-copy'

export default defineConfig({
  plugins: [
    preact(),
    ssr({ prerender: true }),
    viteStaticCopy({
      targets: [
        {
          src: 'public/assets/icons/favicon.svg', // this is a placeholder string, so we have this script to be executed once
          dest: `path/to/dir`,
          rename: 'filename.pdf',
          transform: {
            encoding: 'buffer',
            handler: async (_content, path) => {
              console.log(1)
              try {
                const response = await fetch(URL)
                const json = await response.json()

                console.log(json)
    
                return await processJson(json)
              } catch (e) {
                console.log(path)
                console.log(e)
              }
            },
          },
        }
      ]
    })
  ],
});

而在里面，包括在内，npm run dev都没有被打印出来。我唯一看到的是console.logviteStaticCopyprocessJson[vite-plugin-static-copy] Collected 1 items.

我怎样才能解决这个问题？