cast: rpc --json should format as json

[jsvisa]

Motivation

Seems the --json arg is not enabled for cast rpc, it always return a long string whether or not --json was enabled.

Solution

PR Checklist

• Added Tests
• Added Documentation
• Breaking changes

[DaniPopes]

i mean it's already json, i don't know if it makes much sense to use --json as a pretty flag, in any case you can serde_json::to_string_pretty directly in the cast rpc function

[jsvisa]

Yeah, you can pass the result to json pretty tools(eg: jq), but if we can directly format them, then no need to relay on 3rd tools. As in some workflows, we need the sudo permission to install every software, so if cast can directly format it, it will be more useful.

And the behavior of cast call will also pretty print the json result:

foundry/crates/cast/src/lib.rs

Lines 202 to 205 in 0776fe3

	} else if shell::is_json() {
	let tokens = decoded.iter().map(format_token_raw).collect::<Vec<_>>();
	serde_json::to_string_pretty(&tokens).unwrap()
	} else {

[mattsse]

imo this is okay, this is more or less the same as | jq

since we have this same behaviour elsewhere already I'm okay with this