Logs are discarded on error

[hu55a1n1]

Crate

ibc

Summary of Bug

The current handlers' implementation discards logs when an error is encountered.

Version

v0.11.1

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[hu55a1n1]

Might be related -> cosmos/cosmos-sdk#10618

[hu55a1n1]

Suggestion from @plafer (informalsystems/hermes#1838 (comment)) ->

pub fn deliver<Ctx>(ctx: &mut Ctx, message: Any) -> Result<(Vec<IbcEvent>, Vec<String>), Error>

We could create RouterOutput and RouterResult types, analogous to HandlerOutput and HandlerResult. This would make it more explicit that Vec represents the logs.
dispatch() would then return a RouterResult.

struct RouterOutput {
    events: Vec<IbcEvent>,
    logs: Vec<String>,
}

type RouterResult = Result<RouterOutput, Error>;

[plafer]

This is fixed by the new ValidationContext: logs are no longer returned, but rather given to the context with log_message().

We can close this after the pre-ADR 5 handlers are fully removed.

[plafer]

Completed with the whole ADR 5 #322 work.