NoOp Impl Polling Trait

[Doordashcon]

Adds NoOp implementation for the Polling trait and updates benchmarks in pallet-ranked-collective.

[bkchr]

@Doordashcon do you have any reasoning for this?

[Doordashcon]

@bkchr just a follow up on this?
polkadot-fellows/runtimes#347 (comment)

[bkchr]

@bkchr just a follow up on this?
polkadot-fellows/runtimes#347 (comment)

The comment is saying that this no-op should be implemented on () or some special NoOp struct.

[Doordashcon]

Implemented Polling for () and updated the tests where we have methods unimplemented!().

[Doordashcon]

Added Default bound.

please review @muharem @bkchr

[bkchr]

@Doordashcon can you please fix it as done in this pr #3049?

[bkchr]

Generally looking good, just some nitpicks

[bkchr]

Why do we need Default?

[Doordashcon]

Id -----> tracks, tracks -----> classes in pallet_referenda's implementation of the Polling trait.

polkadot-sdk/substrate/frame/referenda/src/lib.rs

Lines 750 to 752 in c987da3

	fn classes() -> Vec<Self::Class> {
	T::Tracks::tracks().iter().map(|x| x.0).collect()
	}

[ggwpez]

This is a breaking change (major bump in the prdoc), since it can break existing code.
If it is something that is only needed for benchmarking, then the benchmark can use a where clause to only work if the Id is Default, but not requiring it on the trait itself. (the trait does not care about benchmarks).

For example like here:

polkadot-sdk/bridges/snowbridge/pallets/outbound-queue/src/benchmarking.rs

Line 19 in 2ab3f03

<T as Config>::MaxMessagePayloadSize: Get<u32>,

[Doordashcon]

@bkchr @muharem please review

[Doordashcon]

It is known that both extrinsics each involve a single read operation. This can be manually accounted for, rather than relying on the default value for a non existent class. Would you agree with this approach @bkchr?

let class_exists = T::Polls::classes().into_iter().next().is_some();
        let class = if class_exists {
            T::Polls::classes().into_iter().next().unwrap() // Assuming there's at least one class here
        } else {
            return Err(BenchmarkError::Override(BenchmarkResult::from_weight(
                T::DbWeight::get().reads(1),
            )));
      };

[bkchr]

See this.

[Doordashcon]

please review @bkchr

I saw no other way to create an invalid poll for a NoOp Poll than adding From<u8> bound to the Index type

[Doordashcon]

Hopefully we get to backport the Secretary Collective after this is merged @bkchr @muharem

[ggwpez]

Going to approve since am async, but could still be worth to try and remove the additional added requirements in the traits.

[Doordashcon]

Thanks for the benchmarking tip @ggwpez should be ready to merge now!