XCM WeightTrader: Swap Fee Asset for Native Asset (#1845)

Implements an XCM executor `WeightTrader`, facilitating fee payments in
any asset that can be exchanged for a native asset.

A few constraints need to be observed:
- `buy_weight` and `refund` operations must be atomic, as another weight
trader implementation might be attempted in case of failure.
- swap credit must be utilized since there isn’t an account to which an
asset of some class can be deposited with a guarantee to meet the
existential deposit requirement. Also, operating with credits enhances
the efficiency of the weight trader -
https://github.com/paritytech/polkadot-sdk/pull/1677

related PRs:
- (depends) https://github.com/paritytech/polkadot-sdk/pull/2031
- (depends) https://github.com/paritytech/polkadot-sdk/pull/1677
- (caused) https://github.com/paritytech/polkadot-sdk/pull/1847
- (caused) https://github.com/paritytech/polkadot-sdk/pull/1876

// DONE: impl `OnUnbalanced` for a `fungible/s` credit
// DONE: make the trader free from a concept of a native currency and
drop few fallible conversions. related issue -
https://github.com/paritytech/polkadot-sdk/issues/1842
// DONE: tests

---------

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>
Co-authored-by: Liam Aharon <liam.aharon@hotmail.com>
This commit is contained in:
Muharem
2024-01-16 15:34:48 +08:00
committed by GitHub
parent 4c4963a192
commit 2cb39f8dc9
25 changed files with 1769 additions and 861 deletions
@@ -47,6 +47,16 @@ pub type TrustBackedAssetsConvertedConcreteId<TrustBackedAssetsPalletLocation, B
/// AssetId used for identifying assets by MultiLocation.
pub type MultiLocationForAssetId = MultiLocation;
/// [`MatchedConvertedConcreteId`] converter dedicated for `TrustBackedAssets`
pub type TrustBackedAssetsAsMultiLocation<TrustBackedAssetsPalletLocation, Balance> =
MatchedConvertedConcreteId<
MultiLocationForAssetId,
Balance,
StartsWith<TrustBackedAssetsPalletLocation>,
Identity,
JustTry,
>;
/// [`MatchedConvertedConcreteId`] converter dedicated for storing `AssetId` as `MultiLocation`.
pub type MultiLocationConvertedConcreteId<MultiLocationFilter, Balance> =
MatchedConvertedConcreteId<