Issues with Generic Type Inference in atomFamily causing duplicate Atom Key errors in Recoil

[ArthurGuez]

I’m trying to use Recoil's atomFamily with TypeScript generics to get precise type inference. However, I’m encountering errors related to duplicate atom keys. Here's a simplified version of the code I'm using:

I initially defined my atomFamily like this:

export const fieldUpdatedValueState = atomFamily<unknown, { fieldId: string; formId: string }>({
  key: 'fieldUpdatedValueState',
  default: undefined,
  effects: ({ formId, fieldId }) => [
    ({ onSet }) => {
      onSet((newData, _, isReset) => {
        if (isReset || spec(isNullOrUndefinedOrEmpty).test(newData)) {
          actionsResolver.resetChange(formId, fieldId);
        } else {
          actionsResolver.addChange(formId, fieldId);
        }
      });
    },
  ],
});

I then modified it to use a generic type:

export const fieldUpdatedValueState = <T extends FieldIds>() =>
  atomFamily<Fields[T], { fieldId: T; formId: string }>({
    key: 'fieldUpdatedValueState',
    default: undefined,
    effects: ({ formId, fieldId }) => [
      ({ onSet }) => {
        onSet((newData, _, isReset) => {
          if (isReset || spec(isNullOrUndefinedOrEmpty).test(newData)) {
            actionsResolver.resetChange(formId, fieldId);
          } else {
            actionsResolver.addChange(formId, fieldId);
          }
        });
      },
    ],
  });

I use a custom hook to interact with this atom family:

export function useSetField<T extends keyof Fields>(formId: string, fieldId: T) {
  const fieldUpdatedValue = fieldUpdatedValueState<T>();

  return useSetRecoilState(fieldUpdatedValue({ formId, fieldId }));
}

After refactoring to use the generic type, I’m seeing multiple console errors like:

Expectation Violation: Duplicate atom key "fieldUpdatedValueState__{"fieldId":"station_id[]","formId":"list"}".
Expectation Violation: Duplicate atom key "fieldUpdatedValueState__{"fieldId":"search","formId":"list"}".
Expectation Violation: Duplicate atom key "fieldUpdatedValueState__{"fieldId":"status[]","formId":"list"}".

What could be causing these duplicate atom key errors? It seems like using a function to create the atomFamily is leading to these issues. How can I properly use generics with atomFamily without running into duplicate key problems?