No error check leads to chrash

[notreadyyet]

May I ask whether you intend to change classes derived from AbstractMethods to check for errors returned by ClientInterface? I see that three days ago Personal::unlockAccount was changed to check for errors, but IMHO that change didn’t go far enough. I think that to be useful in the real-world applications all functions should call getRpcErrorCode before calling getRpcResult. Also I think that error code and error message should be stored by the AbstractMethods alongside the $client variable to be retrieved by EthereumClient.

[notreadyyet]

Please find in the attachment the changes I've made locally.
Methods.zip
The getTransactionByHash method that used to crash because of this error:
{"jsonrpc":"2.0","id":1,"error":{"code":-32000,"message":"authentication needed: password or unlock"}}
now looks like this:

public function getTransactionByHash(TransactionHash $hash): ?TransactionInfo
{
    $response = $this->client->send(
        $this->client->request(1, 'eth_getTransactionByHash', [$hash->toString()])
    );
    if (!$this->fnHasRes($response)) {
    	return null ;
    }

    return new TransactionInfo($this->getRpcResult()) ;
}

[notreadyyet]

Oups wrong method. It was sendTransaction that crashed, but the change is the same:
public function sendTransaction(Transaction $transaction): ?TransactionHash
{
$response = $this->client->send(
$this->client->request(1, 'eth_sendTransaction', [$transaction->toArray()])
);
if (!$this->fnHasRes($response)) {
return null ;
}

    return new TransactionHash($this->getRpcResult());

}

[notreadyyet]

Now the client instead of crashing can retrieve error information and do something about it like so:

	$transaction = new \EthereumPHP\Types\Transaction(
			$myAddress,
			$otherAddress,
			null,
			null,
			null,
			(new \EthereumPHP\Types\Ether(5))->toWei()->amount()
			);
	$t1 = $client->eth()->sendTransaction($transaction) ;      // this can return null
	$oErr = $client->eth()->fnGetRes() ;                // this allows us to find out why $t1 is null
	if (isset($t1)) {
		$t1 = $t1->toString();
	}