Hex and Base64 interop in TypeScript

hex-base64.ts

const hexToBase64 = (hex: string) =>
  btoa(
    String.fromCharCode(
      ...(hex.match(/[0-9a-f]{2}/gi) ?? []).map((c) => parseInt(c, 16))
    )
  );

const base64ToHex = (base64: string) =>
  [...atob(base64)]
    .map((c) => c.charCodeAt(0).toString(16).padStart(2, "0"))
    .join("");

/**
 * test 1
 */
{
  const base46Str = "B9PlPiWDr2Ve2EpZVvBL";
  console.log(base64ToHex(base46Str));
  console.assert(hexToBase64(base64ToHex(base46Str)) === base46Str);
}

/**
 * test 2
 */
{
  const hexString = "a0eebc999c0b4ef8bb6d6bb9bd380a11";
  console.log(hexToBase64(hexString));
  console.assert(base64ToHex(hexToBase64(hexString)) === hexString);
}