How to test a pallet that depends on the staking pallet?

Question

If I have a pallet that depends on the staking pallet, and for example one of the functions needs access to the active era, how can I set up the test environment so that I can actually test this?

Let's say I am accessing the active era like this:

let active_era = Staking::<T>::active_era().ok_or(/*...*/)

I have checked the mock.rs file in the staking pallet directory, and it sets up all the configs and sets up the environment needed for testing the staking pallet.

For my pallet, I need to set up the staking pallet because my pallet is dependent on it. I was thinking of accessing the ExtBuilder from the staking pallet, but it is a bit more complex than just importing it at the beginning of the file. It's because the staking/src/mock.rs file is only compiled when testing the pallet. So when I am testing only my pallet it isn't possible to access the ExtBuilder from the staking pallet. This means that I can't access anything from the mock.rs file inside the staking pallet.

How should I go about setting up the staking pallet for testing my own pallet?

Answer 1

You will need to add the Staking Pallet into your mock construct_runtime!:

From frame/session/benchmarking/src/mock.rs:

frame_support::construct_runtime!(
    pub enum Test where
        Block = Block,
        NodeBlock = Block,
        UncheckedExtrinsic = UncheckedExtrinsic,
    {
        System: frame_system::{Pallet, Call, Config, Storage, Event<T>},
        Balances: pallet_balances::{Pallet, Call, Storage, Config<T>, Event<T>},
        Staking: pallet_staking::{Pallet, Call, Config<T>, Storage, Event<T>},
        Session: pallet_session::{Pallet, Call, Storage, Event, Config<T>},
    }
);

At this point, you should be able to access public functions from the staking module via the Staking struct which is defined in the construct_runtime!.

So you should be able to call:

let active_era = Staking::<T>::active_era().ok_or(/*...*/)

Exactly as you have wanted in your main post.