if no wallet name was provided, use one derived from the descriptor

[ulrichard]

Description

if no wallet name was provided, use one derived from the descriptor

Notes to the reviewers

Is there a better place to use wallet_name_from_descriptor so that the generated name shows up in the unit tests instead of the placeholder?

Checklists

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• [x] I ran cargo fmt and cargo clippy before committing

[notmandatory]

How about making WalletOpts.wallet an Option<String> ? Then you could avoid the "main_marker_will_be_replaced" default value and only do the replacement when WalletOpts.wallet is None; such as in the open_database function you can use unwrap_or to call your wallet_name_from_descriptor function.

[ulrichard]

@notmandatory Yes, of course. Sometimes the solution is so obvious that I have no clue why I didn't find it myself. Thanks.