[Bug]: "../public" is always copied in the static build root even if I set it to go elsewhere

[speyou]

Describe the bug

I can put anything I like into the staticDirs config option, "../public" will always be copied at the root of the storybook-static folder during the last phase of the build.
My problem is: "../public" contains data unrelated to Storybook (for instance pdf document to download in the app) and, more importantly, "../public" contains an index.json file that will override the storybook generated index.json, breaking the build in the process (because without the index, stories are not found).

If it's working as intended, could someone point out how I can go over that and NOT copy index.json into "/storybook-static"?

To Reproduce

1. Create a new app with storybook (for instance npm create vite@latest then npx storybook@latest init)
2. Create a file public/index.json and put an empty JSON inside {}
3. Set the staticDirs to anything other than ../public, for instance staticDirs: [ { from: "../public", to: "/foo" } ],
4. Run the storybook build npm run build-storybook
5. storybook-static/index.json doesn't contain the necessary data (should be something like { v:4, entries: {...) but instead is set at whatever you put in the public/index.json file (in this example, it's {})
6. storybook-static/foo contains a copy of whatever was in the ../public folder (so the staticDirs property works BUT the copy is done twice, once at the root, once at the directory I asked it to use)

System

No response

Additional context

No response

[ferg-usi]

I am having the same issue. Any resolution @speyou ?

[allanhortle]

Double check it's not vite doing the copying. I just spent a too long trying to figure out why this was happening. In the end setting publicDir: false in the vite config solved the problem.

[Sidnioulz]

If someone could please confirm that publicDir: false in the Vite config solves the issue, we could either switch up the default in our own Vite config (@shilman is this relied on by existing users? what do you think? should we set a default staticDirs that matches the default Vite config, so our users can override it to []?) or document this side effect for Vite users in this doc page.

[tetsu-wang]

Hi there, I'm new here but wanted to chip in.

I found that both publicDir: false and build.copyPublicDir: false solve the issue.
However, since i think Storybook handles static assets independently of Vite, I believe setting publicDir: false is the cleaner approach.

Here is the reproduction link:
https://stackblitz.com/edit/github-plqxwn6d?file=.storybook%2Fmain.ts&view=editor