Consider the following snippet

        #[weight = 100_000_000] //TODO: update weights
        pub fn test(
            _outputs: frame_support::BoundedBTreeSet<JoyBalanceOf<T>, <T as Config>::MaxOutputs>
        ) -> DispatchResult {

MaxOutputshas been defined in the Config trait as

pub type MaxOutputs = Get<u32>;

When running clippy this will result in the following error

 error[E0277]: `BoundedBTreeSet<<T as pallet_balances::Config>::Balance, <T as Config>::MaxOutputs>` doesn't implement `core::fmt::Debug`
     --> /home/ignazio/developer/joystream/runtime-modules/project-token/src/lib.rs:219:1
  219 | / decl_module! {
  220 | |     pub struct Module<T: Config> for enum Call
  221 | |     where
  222 | |         origin: T::Origin
  ...   |
  993 | |     }
  994 | | }
      | |_^ `BoundedBTreeSet<<T as pallet_balances::Config>::Balance, <T as Config>::MaxOutputs>` cannot be formatted using `{:?}` because it doesn't implement `core::fmt::Debug`
      = help: the trait `core::fmt::Debug` is not implemented for `BoundedBTreeSet<<T as pallet_balances::Config>::Balance, <T as Config>::MaxOutputs>`
      = help: the following other types implement trait `core::fmt::Debug`:
                (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11)
                (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11)
                (T10, T11)
                (T2, T3, T4, T5, T6, T7, T8, T9, T10, T11)
                (T3, T4, T5, T6, T7, T8, T9, T10, T11)
                (T4, T5, T6, T7, T8, T9, T10, T11)
              and 5 others
      = note: this error originates in the macro `$crate::format_args` (in Nightly builds, run with -Z macro-backtrace for more info)

However when replacing the BoundedBTreeSet with its unbounded BTreeSet version no errors of this kind are thrown.


  • frame-support: 4.0.0-dev
  • cargo: 1.62.0-nightly (a44758ac8 2022-05-04)


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