[Code Quality]: Remove unused #[cfg] attibutes and fix all clippy warnings

[Davidson-Souza]

Clippy gives warnings about unused features, most of them are either related to the cli-blockchain or the slip132 code. The former can be removed altogether, while the latter can be simplified a lot.

[siddheshzz]

Hello @Davidson-Souza , can i give it a try to this.

Upon looking at the code base i found-
For unused #[cfg] attributes, I can see some are disabled by default which can be removed and most of them related to

#[cfg(feature = "metrics")]
#[cfg(not(feature = <FEATURE>))].                           eg - #[cfg(not(feature = "bitcoinconsensus"))]

#[cfg(feature = "cli-blockchain")]
#[error("Json-Rpc error")]
JsonRpcError(#[from] UtreexodError),



#[cfg(feature = "zmq-server")]
#[cfg(target_env = "gnu")]

}

For Clippy warning :

warning: this expression creates a reference which is immediately dereferenced by the compiler
   --> crates/floresta-wire/src/p2p_wire/node.rs:230:44
    |
230 |                 Self::resolve_connect_host(&address, Self::get_port(config.network.into()))
    |                                            ^^^^^^^^ help: change this to: `address`
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
    = note: `#[warn(clippy::needless_borrow)]` on by default

warning: `floresta-wire` (lib) generated 1 warning (run `cargo clippy --fix --lib -p floresta-wire` to apply 1 suggestion)

I will give it a try if this sound good.
Thanks

[Davidson-Souza]

Hi @siddheshzz. Thanks for taking a look at this.

Most of those #[cfg] are still useful. bitcoinconsensus, metrics, zmq and json-rpc for example are features we support. Useless mean that we don't have a corresponding feature on the manifest, and clippy will warn about it.

[siddheshzz]

Hi @Davidson-Souza , Thank you for your time.

I am trying to understand few things, please bare with me
On cargo +nightly clippy --all-targets i found few [cfg] warnings - i checked in manifest the feature is not listed
.

1. In slip132 serde is not explicitly listed under the features section in Cargo.toml but its working fine as an enabled one.
   On reading more on this i found the feature can be implicitly Enabled by another feature(Transitive).
   I tried to add feature serde:["dep:serde"] but this wont work as it will break other Serialization and Deserialization so i imported those.
   I added new feature to cargo.toml making serde and strict_encoding as optional ,enabling serde feature-

serde = { version = "1.0", features = ["derive"], optional = true }
strict_encoding = { version = "1.0", optional = true }
.
.
serde = ["dep:serde"]
default = ["experimental-p2p", "json-rpc", "serde"]

2. #[cfg(feature = "cli-blockchain")] also came up in warning which was mostly used in Error enum for UtreexodError(UtreexodError),- Removed these #[cfg] and also check all references if any was in use.

Ran cargo test --release - no test breaking/failing

Now the clippy wont show any #[cfg] slip132 & cli-blockchain related warnings.

Is this sound ok or we need some other approach

[Davidson-Souza]

For 1, the code can be massively simplified, and we can assume that serde is always available (we use it for config parsing in florestad)

For 2. This module can be removed as whole, we don't use it any more.

If you want, you can make one pr for each, and another one fixing the last few warnings

[siddheshzz]

We can close this ref- #361 & #367

[Davidson-Souza]

We can close this ref- #361 & #367

I still see some warnings when I run just lint