CVA prop splitting

cva.tsx

import { cva } from "cva";

export * from "cva";

type Base = Parameters<typeof cva<unknown>>[0];
type Config<T> = Parameters<typeof cva<T>>[1];
type Simplify<T> = { [KeyType in keyof T]: T[KeyType] } & {};
type Props<T> = Simplify<
  Omit<
    Exclude<Parameters<ReturnType<typeof cva<T>>>[0], undefined>,
    "className" | "class"
  >
>;

export const cvaSplit =
  <T,>(base?: Base, config?: Config<T>) =>
  <U,>(
    props: Props<T> & U,
  ): Omit<U, keyof Props<T> | "className" | "class"> & {
    className: string;
  } => {
    let rest: any = {};
    if (config?.variants) {
      for (const k in props) {
        if (!(k in config.variants) && k !== "class" && k !== "className") {
          rest[k] = (props as any)[k];
        }
      }
    } else {
      rest = { ...props };
    }
    rest.className = cva(base, config)(props as any);
    return rest;
  };