Typescript: FunctionField without record like data typing limitation

[JinParc]

What you were expecting:

I tried to give a type definition to a FunctionField. As you can see on sandbox below, I gave backlinks property as a type which belong to PostRecord to FunctionField. However, type error occurs.

I assume this type error occurs because backlinks type is a type property of the PostRecord not a record itself.

It would be nice if a FunctionField would be able to accept another kind of object type than a record.

What happened instead:

Type error with a message Type 'foo' does not satisfy the constraint 'Record'

Related code:

https://codesandbox.io/s/crazy-dan-2x2prk?file=/src/posts/PostShow.tsx (line#58)

  <FunctionField<
           Required<PostRecord>['backlinks'][number]
  >
           source="info"
           render={r =>`${r.info.email}`}
  />

Related types

type BackLinkProps = Array<{
  date?: string;
  url?: string;
  info?: {
      email?: string;
      nationality?: string;
  };
}>;

export interface PostRecord extends Record {
  id: number;
  title: string;
  teaser?: string;
  body?: string;
  view?: number;
  average_note?: number;
  commentable?: boolean;
  pictures?: Array<ImageProps>;
  published_at?: Date;
  tags?: Array<number>;
  category?: string;
  subcategory: string;
  backlinks?: Array<BackLinkProps>;
  notifications: Array<number>;
}

Other information:

Environment

• React-admin version: 3.19.7
• React version: 17.0.2
• Browser: Chrome 101

[slax57]

Hi!
Indeed in the case of an ArrayField, the record does not necessary have to have an id.
So we could enlarge the type to be any object (any being the default type btw).
Meanwhile, as a workaround, you can simply change to:

  <FunctionField<
-          Required<PostRecord>['backlinks'][number]
+          Required<PostRecord>['backlinks'][number] & RaRecord
  >
           source="info"
           render={r =>`${r.info.email}`}
  />

[JinParc]

Thank you! @slax57

I will consider to be with workaround while awaiting this issue is fixed :)

[fzaninotto]

The problem goes beyond FunctionField: All fields used as child of ArrayField should work on a non-record. But only the FunctionField is generic for now.

I'm not sure how we should fix that.

All fields should be able to work on non-records. So at least, for FunctionField, the generic type shouldn't extend RecordType