byte[] input, String algorithm, SecretKey key, HashFunction hashFunc) throws Exception {
    Mac mac = Mac.getInstance(algorithm);
    mac.init(key);
    mac.update(input);

    assertEquals(HashCode.fromBytes(mac.doFinal()), hashFunc.hashBytes(input));
    assertEquals(HashCode.fromBytes(mac.doFinal(input)), hashFunc.hashBytes(input));
  }

  // Tests from RFC2022: https://tools.ietf.org/html/rfc2202

pkg crypto, method (Hash) HashFunc() Hash
pkg crypto, type Signer interface { Public, Sign }
pkg crypto, type Signer interface, Public() PublicKey
pkg crypto, type Signer interface, Sign(io.Reader, []uint8, SignerOpts) ([]uint8, error)
pkg crypto, type SignerOpts interface { HashFunc }
pkg crypto, type SignerOpts interface, HashFunc() Hash
pkg crypto/ecdsa, method (*PrivateKey) Public() crypto.PublicKey

pkg crypto/ecdsa, method (*PublicKey) ECDH() (*ecdh.PublicKey, error) #56088
pkg crypto/ed25519, func VerifyWithOptions(PublicKey, []uint8, []uint8, *Options) error #31804
pkg crypto/ed25519, method (*Options) HashFunc() crypto.Hash #31804
pkg crypto/ed25519, type Options struct #31804
pkg crypto/ed25519, type Options struct, Context string #31804
pkg crypto/ed25519, type Options struct, Hash crypto.Hash #31804