Errors dealing with Ed25519 keys and certificates

[danicuki]

I have this private key:

-----BEGIN PRIVATE KEY-----
MC4CAQAwBQYDK2VwBCIEIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
-----END PRIVATE KEY-----

I can successfully read it using:

{:ok, k} = X509.PrivateKey.from_pem("-----BEGIN PRIVATE KEY-----\nMC4CAQAwBQYDK2VwBCIEIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\n-----END PRIVATE KEY-----")

{:ok,
 {:ECPrivateKey, 1,
  <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0>>, {:namedCurve, {1, 3, 101, 112}}, :asn1_NOVALUE,
  :asn1_NOVALUE}}

when I run openssl pkey -in key.pem -pubout I get:

$  openssl pkey -in ./test/system/network/alice_key.pem -pubout
-----BEGIN PUBLIC KEY-----
MCowBQYDK2VwAyEAO2onvM62pC1io6jQKm8Nc2UyFXcd4kOmOsBIoYtZ2ik=
-----END PUBLIC KEY-----

But when I take the existing key and convert it to pem again I get:

 IO.puts X509.PrivateKey.to_pem(k)
-----BEGIN EC PRIVATE KEY-----
MCwCAQEEIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAoAUGAytlcA==
-----END EC PRIVATE KEY-----

(different from the original key)

and when I run openssl pkey -in generated_key.pem -pubout (with this new output), I get:

$ openssl pkey -in teste.pem -pubout
Could not find private key of key from teste.pem
40F8B1FE01000000:error:1608010C:STORE routines:ossl_store_handle_load_result:unsupported:crypto/store/store_result.c:151:

There is something wrong with this key pem generation. Am I doing something wrong or is this a bug?