Problem

In the Basilisk runtime, the KSM token's reserve is set to Location::parent(); this is relative to itself, meaning it refers to the relay chain.
See:

Post-AHM, the reserve is Asset Hub, i.e. parachain 1000. This breaks horizontal KSM token transfers, as xTokens incorrectly routes through the relay instead of AH.

Changes

• chain_part(): (1, _) → Location::new(1, [Parachain(1000)]) instead of Location::parent()

• AbsoluteReserveProvider/RelativeReserveProvider moved from orml_traits::location to orml_xtokens

  • this is a breaking change

• Added ASSET_HUB_ID = 1000 constant in traits/src/location.rs

• Mock tests updated: Asset Hub parachain added; relay trusts AH for teleports

Based on open-web3-stack#1033. open-web3-stack#1035.

Validation

Validated with Polkadot Ecosystem Tests (basilisk.karura.xcm suite).

1. Current behavior: Basilisk -> Karura transfer of KSM produced empty HRMP messages, zero balance on the destination chain, Karura

   • Note how Karura -> Basilisk transfers of KSM work

2. Behavior with this patch: after building the Basilisk runtime with its ORML dependencies patched to this PR's branch and running PET with BASILISK_WASM override, the Basilisk -> Karura KSM transfer worked.

Reproducing with PET

1. Patch the ORML dependencies in the Basilisk repo to point to this PR's branch
2. Build the Basilisk runtime:

   cargo build --release -p basilisk-runtime

3. Clone PET and install deps:

   git clone https://github.com/AcalaNetwork/polkadot-ecosystem-tests
   cd polkadot-ecosystem-tests && yarn install

4. Run with wasm override:

   BASILISK_WASM=/path/to/basilisk_runtime.compact.compressed.wasm yarn test basilisk.karura.xcm