Currently `transfer_assets` from pallet-xcm covers 4 main different
transfer types:
- `localReserve`
- `DestinationReserve`
- `Teleport`
- `RemoteReserve`
For the first three, the local execution and the remote message sending
are separated, and fees are deducted in pallet-xcm itself:
https://github.com/paritytech/polkadot-sdk/blob/3410dfb3929462da88be2da813f121d8b1cf46b3/polkadot/xcm/pallet-xcm/src/lib.rs#L1758.
For the 4th case `RemoteReserve`, pallet-xcm is still relying on the
xcm-executor itself to send the message (through the
`initiateReserveWithdraw` instruction). In this case, if delivery fees
need to be charged, it is not possible to do so because the
`jit_withdraw` mode has not being set.
This PR proposes to still use the `initiateReserveWithdraw` but
prepending a `setFeesMode { jit_withdraw: true }` to make sure delivery
fees can be paid.
A test-case is also added to present the aforementioned case
---------
Co-authored-by: Adrian Catangiu <adrian@parity.io>
Issues addressed in this PR:
- Improve *Penpal* runtime:
- Properly handled received assets. Previously, it treated `(1, Here)`
as the local native currency, whereas it should be treated as a
`ForeignAsset`. This wasn't a great example of standard Parachain
behaviour, as no Parachain treats the system asset as the local
currency.
- Remove `AllowExplicitUnpaidExecutionFrom` the system. Again, this
wasn't a great example of standard Parachain behaviour.
- Move duplicated
`ForeignAssetFeeAsExistentialDepositMultiplierFeeCharger` to
`assets_common` crate.
- Improve emulated tests:
- Update *Penpal* tests to new runtime.
- To simplify tests, register the reserve transferred, teleported, and
system assets in *Penpal* and *AssetHub* genesis. This saves us from
having to create the assets repeatedly for each test
- Add missing test case:
`reserve_transfer_assets_from_para_to_system_para`.
- Cleanup.
- Prevent integration tests crates imports from being re-exported, as
they were polluting the `polkadot-sdk` docs.
There is still a test case missing for reserve transfers:
- Reserve transfer of system asset from *Parachain* to *Parachain*
trough *AssetHub*.
- This is not yet possible with `pallet-xcm` due to the reasons
explained in https://github.com/paritytech/polkadot-sdk/pull/3339
---------
Co-authored-by: command-bot <>
I found out during the cleanup of this deprecation message in the
`polkadot-fellows` repository that we deprecated `CurrencyAdapter`
without making the recommended changes.
## TODO
- [ ] fix `polkadot-fellows` bump to 1.6.0
https://github.com/polkadot-fellows/runtimes/pull/159
---------
Co-authored-by: Francisco Aguirre <franciscoaguirreperez@gmail.com>
girazoki