[BUG] useAction.inputissue with zod-form-data

[armandabric]

Are you using the latest version of this library?

• I verified that the issue exists in the latest next-safe-action release

Is there an existing issue for this?

• I have searched the existing issues and found nothing that matches

Describe the bug

When using next-safe-action with zod-safe-action schema, the useAction(...).input type is not inferred correctly.

In the action body the input type is ok:

const schema = zfd.formData({
  bar: zfd.text(z.string().min(3).max(10)),
});

export const doSomethingWithZodFormData = actionClient
  .schema(schema)
  .action(async ({ parsedInput: { bar } }) => {
    // Here the `bar` input is a `string` as expected
    const baz: string = bar;

    return { /* ... */ };
  });

The issue is only with the hook:

const doSomethingWithZodFormActionAction = useAction(doSomethingWithZodFormData)

// With a schema made with zod-safe-action, the input type is not ok: `FormData | FormDataLikeInput`
const bar = doSomethingWithZodFormActionAction.input?.bar

The issue also present with the useAction(...).execute function.

Everything works correctly when using a zod schema.

Reproduction steps

In the linked reproduction sandbox, if you open the app/page.tsx file you will see two useAction usage: one with a zod schema, the other with a zod-safe-action schema. The second case trigger a TS error.

Expected behavior

As the input type is well inferred in the action, I'm expecting it to the be inferred when using the useAction hook.

Link to a minimal reproduction of the issue

https://codesandbox.io/p/devbox/epic-torvalds-vt88n4

Library version

7.10.3

Next.js version

15.1.7

Node.js version

20.9.0

Additional context

No response

[chungweileong94]

TLDR;
It's zod-form-data that need to fix its input type for zfd.formData().

It's because zfd.formData() is a Zod effect, where the input type will be inferred as FormData | FormDataLikeInput (https://github.com/airjp73/rvf/blob/d7f7e983f43c5938d48f99dd744827ce9e559b34/packages/zod-form-data/src/helpers.ts#L128), even though you can technically pass in an object thanks to zod-form-data (https://github.com/airjp73/rvf/blob/d7f7e983f43c5938d48f99dd744827ce9e559b34/packages/zod-form-data/src/helpers.ts#L194), but it might not always the case for other Zod effect use cases.

I was once supporting this in my server action library chungweileong94/server-act#35, but I found myself fighting against the types for this specific use-case (zod-form-data), so I ended up ditching it when I adopted standard schema chungweileong94/server-act#37.

[chungweileong94]

This should be fixed in the latest zod-form-data.