XCM simulator

[xlc]

It will be helpful to have some tool to simulate the interaction of XCM related code without having us to run multiple relaychain nodes and parachain nodes.

[bkchr]

By XCM related code you mean your pallets?

[xlc]

Our pallets, other parachain's pallets, but most importantly xcm-executor/builder from Polkadot and maybe xcm-handler from Cumulus.

Right now to run a XCM message, it starts from our pallet, uses xcm-builder in Polkadot, call into xcm-handler from Cumulus, which calls xcm-executor from Polkadot, and to go relaychain, routed to dest parachain, call into xcm-handler, call into xcm-executor, call into custom pallet code.

Too many moving parts over multiple process. Will be helpful to be able to run the whole thing in a single integration test.

Otherwise how do I even write test for our XCM related pallets?

[bkchr]

CC @shawntabrizi @pepyakin

[jak-pan]

We're trying to do integration tests and will also probably do these with https://github.com/halva-suite/halva but it needs some upgrades since it's little bit outdated. cc @martinfridrich but this is interesting :) Would be faster for preliminary tests.

[shawntabrizi]

closed by #3538