How to use an outer mock inside `impl_benchmark_test_suite`?

Question

Hey valuable Substrate pros,

do you know a way to use impl_benchmark_test_suite inside another crate like the runtime? I have multiple pallets. There are no mocks inside these pallets. There is only one runtime mock in my project. Since impl_benchmark_test_suite needs the mock, I would like to find a way to call the benchmark tests in an outer crate like the runtime.

#[cfg(test)]
#[cfg(feature = "runtime-benchmarks")]
mod benchmark_tests {
    use super::*;
    use frame_benchmarking::impl_benchmark_test_suite;

    impl_benchmark_test_suite!(
        my_pallet_1::Pallet,
        crate::mock::ExtBuilder::default().build(),
        crate::mock::Test,
        benchmarks_path = my_pallet_1::benchmarking,
    );

    impl_benchmark_test_suite!(
        my_pallet_2::Pallet,
        crate::mock::ExtBuilder::default().build(),
        crate::mock::Test,
        benchmarks_path = my_pallet_2::benchmarking,
    );

    impl_benchmark_test_suite!(
        my_pallet_3::Pallet,
        crate::mock::ExtBuilder::default().build(),
        crate::mock::Test,
        benchmarks_path = my_pallet_3::benchmarking,
    );
}

This produces that error:

error: no rules expected the token `::`

my_pallet_1::Pallet

no rules expected this token in macro call

EDIT:

Trying to use the benchmark test module inside the mock of the runtime:

#[cfg(feature = "runtime-benchmarks")]
mod benchmark_tests {
    use frame_benchmarking::impl_benchmark_test_suite;

    use my_pallet::Pallet;

    impl_benchmark_test_suite!(
        Pallet,
        ExtBuilder::default().build(),
        Test,
        benchmarks_path = my_pallet::benchmarking,
    );
}

This produces this error:

error: no rules expected the token `)`
375 | /     impl_benchmark_test_suite!(
376 | |         Pallet,
377 | |         ExtBuilder::default().build(),
378 | |         Test,
379 | |         benchmarks_path = my_pallet::benchmarking,
380 | |     );
    | |_____^ no rules expected this token in macro call

EDIT 2:

I tried another approach: Just using the mock runtime and ExtBuilder from another pallet.

Inside my_pallet/benchmarking.rs:

impl_benchmark_test_suite!(Pallet, pallet_tests::ExtBuilder::default().build(), pallet_tests::Test);

Although ExtBuilder and Test is public in pallet_tests it produces the following error:

failed to resolve: could not find `ExtBuilder` in `pallet_tests`

could not find `ExtBuilder` in `pallet_tests`

cannot find type `Test` in crate `pallet_tests`

Answer 1

I suspect the problem in your approach is using fully qualified paths for the first and fourth argument. Checking in the docs I found the following information:

because of macro syntax limitations, neither Pallet nor benches can be paths, but both have to be idents in the scope of impl_benchmark_test_suite.

So I guess you might try doing something like this:

use my_pallet_1::{Pallet as Pallet1, benchmarking as bench1};

impl_benchmark_test_suite!(
    Pallet1,
    crate::mock::ExtBuilder::default().build(),
    crate::mock::Test,
    benchmarks_path = bench1
);

I haven't tested it though, it's just my suggestion based on the docs.

---

EDIT: This doesn't work, unfortunately. See comments.