I'm using npm bitcoin-core ^2.0.0 to get access to my bitcoind (v0.17.1 MAC)

My code:

let signedRawTx = await btcClient.signRawTransaction(rawTx, [], [privateKey], 'ALL');

I get an error message telling me that signrawtransaction is deprecated, use signrawtransactionwithkey instead.

My problem: I tried to mixed uppercase letters like this:

btcClient.signRawTransactionWithKey(...)
btcClient.signrawtransactionwithkey(...)
btcClient.signRawTransactionWithkey(...)
...

with always the same kind of error:

signRawTransactionWithKey is not a function...

In my text editor, I can see all the available functions for btcClient, signRawTransaction is in the list but nothing like signRawTransactionWithKey. If I type help in the console of bitcoind, I can see signrawtransaction and signrawtransactionwithkey.

Any advice ?