How to solve this error: associated type `BlockNumber` not found for `T`?

Question

I have substrate node template with babe and i want to integrate orml-currencies.

I'm using this in cargo.toml:

orml-currencies = { default-features = false, git = "https://github.com/open-web3-stack/open-runtime-module-library.git", branch = "polkadot-v1.0.0" }

Then I'm getting this error:

--> /Users/deepak/.cargo/git/checkouts/open-runtime-module-library-d3634ee624a28945/6819d3f/tokens/src/lib.rs:433:18
      |
  433 |     impl<T: Config> GenesisBuild<T> for GenesisConfig<T> {
      |                     ^^^^^^^^^^^^ not found in this scope
      |
  help: consider importing this trait
      |
  179 +     use frame_support::traits::GenesisBuild;
      |

  error[E0220]: associated type `BlockNumber` not found for `T`
      --> /Users/deepak/.cargo/git/checkouts/open-runtime-module-library-d3634ee624a28945/6819d3f/tokens/src/lib.rs:1277:19
       |
  1277 |     type Moment = T::BlockNumber;
       |                      ^^^^^^^^^^^ there is a similarly named associated type `BlockNumber` in the trait `BlockNumberProvider`

  error[E0220]: associated type `BlockNumber` not found for `T`
      --> /Users/deepak/.cargo/git/checkouts/open-runtime-module-library-d3634ee624a28945/6819d3f/tokens/src/lib.rs:2403:19
       |
  2403 |     type Moment = T::BlockNumber;
       |                      ^^^^^^^^^^^ there is a similarly named associated type `BlockNumber` in the trait `BlockNumberProvider`

How to solve this issue?

Thanks in advance!

Answer 1

According to the Polkadot Release Analysis v1.0.0, GenesisBuild has been has been deprecated in favor of BuildGenesisConfig. Here is an example of how to use:

#[pallet::genesis_config]
#[derive(frame_support::DefaultNoBound)]
pub struct GenesisConfig<T: Config<I>, I: 'static = ()> {
     _config: sp_std::marker::PhantomData<(T,I)>,
    _myfield: u32,
}
    
#[pallet::genesis_build]
impl<T: Config<I>, I: 'static> BuildGenesisConfig for GenesisConfig<T, I> {
    fn build(&self) {}
}

I believe there was a change with BlockNumber as well:

• https://forum.polkadot.network/t/polkadot-release-analysis-v1-0-0/3585/3#moves-block-to-frame_system-instead-of-construct_runtime-and-removes-header-and-blocknumber-1

I believe you can use BlockNumberFor<T> instead of BlockNumber.

You can reference the Cumulus PR for examples:

• https://github.com/paritytech/cumulus/pull/2790/files