pablomartin4btc

re-ACK 46cca252e30f54b06df011d268ef1b8a48b076e7.

Thanks @kouloumos for taking the time to review this PR, I agree with your comments and I appreciate you added more context into it so people could bring other thoughts....

@jonatack thanks for reviewing; as you and @kouloumos recommended and as I commented [here](https://github.com/bitcoin/bitcoin/pull/26990#issuecomment-1411046166), I've made the validation more generic for any cli-command moving it up in the code. As...

> The only thing i suggest changing is giving a more descriptive error on the following situation : > ``` > $ bitcoin-cli -regtest -generate 1 -rpcwallet=tst2 > error: Error:...

> ACK [0fe610d](https://github.com/bitcoin/bitcoin/commit/0fe610deba336f0370d68c130dc9a223b7db964e) modulo the dangling closing parenthesis in the error message. > Also, the first line of the commit message should be at most 80 chars. I've corrected them...

Rebased. Split the changes into 2 commits: 1. improve current message error; 2. New validation. Updated PR description accordingly.

> style-nit: all variable and function names should be snake_case https://github.com/bitcoin/bitcoin/blob/master/doc/developer-notes.md#coding-style-c. Thanks for checking that, you are right, I'll fix them all ASAP.

I've addressed feedback from @andrewtoth - thank you!

Updates: addressed @andrewtoth's feedback, thanks again!

> It looks safe to me to replace all uses of `std::string` with `std::string_view` in this PR. ~Addressed most, except for `exclusively_command` which involves dynamic changes with different string values...