Field validation functions currently do not type their `value` arg. This
is because the underlying `FieldBase` type breaks the type inferences
for these functions. The fix is to `Omit` the `validate` property from
this type before overriding it with our own, typed version for each
field.
Here's an example of the problem:
<img width="373" alt="Screenshot 2024-09-16 at 2 50 10 PM"
src="https://github.com/user-attachments/assets/a99e32fb-5645-4df6-82f2-0efab26b9831">
Here's an example of the fix:
<img width="363" alt="Screenshot 2024-09-16 at 3 59 42 PM"
src="https://github.com/user-attachments/assets/f83909bc-2169-4378-b5a7-5cca78b6ad64">
This PR also fixes the `hasMany` type inferences (shown above), where
the `value` type changes to an array when this property is set. Here's a
minimal example of the solution:
```ts
export type NumberField = {
type: 'number'
} & (
| {
hasMany: true
validate?: Validate<number[], unknown, unknown, NumberField>
}
| {
hasMany?: false | undefined
validate?: Validate<number, unknown, unknown, NumberField>
}
)
```
```ts
{
type: 'text',
validate: (value) => '' // value is `string`
},
{
type: 'text',
hasMany: true,
validate: (value) => '' // value is `string[]`
}
```
Disclaimer: in order for these types to properly infer their values,
`strictNullChecks: true` must be set in your `tsconfig.json`. This is
_not_ currently set in the Payload Monorepo, but consuming apps _should_
have this defined in order properly infer these types.
This PR also adds stronger types for misc. untyped values such as the
`point` field, etc.