TypeScript

Extracting Variant Types

cva offers the VariantProps helper to extract variant types

// components/button.ts
import type { VariantProps } from "cva";
import { cva, cx } from "cva";

/**
 * Button
 */
export type ButtonProps = VariantProps<typeof button>;
export const button = cva(/* … */);

Required Variants

To keep the API small and unopinionated, cva doesn’t offer a built-in solution for setting required variants.

Instead, we recommend using TypeScript’s Utility Types:

// components/button.ts
import { cva, type VariantProps } from "cva";

export type ButtonVariantProps = VariantProps<typeof buttonVariants>;
export const buttonVariants = cva({
  base: "…",
  variants: {
    optional: { a: "…", b: "…" },
    required: { a: "…", b: "…" },
  },
});

/**
 * Button
 */
export interface ButtonProps
  extends Omit<ButtonVariantProps, "required">,
    Required<Pick<ButtonVariantProps, "required">> {}

export const button = (props: ButtonProps) => buttonVariants(props);

// ❌ TypeScript Error:
// Argument of type "{}": is not assignable to parameter of type "ButtonProps".
//   Property "required" is missing in type "{}" but required in type
//   "ButtonProps".
button({});

// ✅
button({ required: "a" });