1. Apr 17, 2024
    • Sergej Sakac's avatar
      XCM coretime region transfers (#3455) · e6f3106d
      Sergej Sakac authored
      This PR introduces changes enabling the transfer of coretime regions via
      XCM.
      
      TL;DR: There are two primary issues that are resolved in this PR:
      
      1. The `mint` and `burn` functions were not implemented for coretime
      regions. These operations are essential for moving assets to and from
      the XCM holding register.
      2. The transfer of non-fungible assets through XCM was previously
      disallowed. This was due to incorrectly benchmarking non-fungible asset
      transfers via XCM, which led to assigning it a weight of `Weight::Max`,
      effectively preventing its execution.
      
      ### `mint_into` and `burn` implementation
      
      This PR addresses the issue with cross-chain transferring regions back
      to the Coretime chain. Remote reserve transfers are performed by
      withdrawing and depositing the asset to and from the holding registry.
      This requires the asset to support burning and minting functionality.
      
      This PR adds burning and minting; however, they work a bit differently
      than usual so that the associated region record is not lost when
      burning. Instead of removing all the data, burning will set the owner of
      the region to `None`, and when minting it back, it will set it to an
      actual value. So, when cross-chain transferring, withdrawing into the
      registry will remove the region from its original owner, and when
      depositing it from the registry, it will set its owner to another
      account
      
      This was originally implemented in this PR: #3455, however we decided to
      move all of it to this single PR
      (https://github.com/paritytech/polkadot-sdk/pull/3455#discussion_r1547324892)
      
      ### Fixes made in this PR
      
      - Update the `XcmReserveTransferFilter` on coretime chain since it is
      meant as a reserve chain for coretime regions.
      - Update the XCM benchmark to use `AssetTransactor` instead of assuming
      `pallet-balances` for fungible transfers.
      - Update the XCM benchmark to properly measure weight consumption for
      nonfungible reserve asset transfers. ATM reserve transfers via the
      extrinsic do not work since the weight for it is set to `Weight::max()`.
      
      Closes: https://github.com/paritytech/polkadot-sdk/issues/865
      
      
      
      ---------
      
      Co-authored-by: default avatarBranislav Kontur <[email protected]>
      Co-authored-by: default avatarFrancisco Aguirre <[email protected]>
      Co-authored-by: default avatarDónal Murray <[email protected]>
      e6f3106d
  2. Apr 12, 2024
    • Adrian Catangiu's avatar
      pallet-xcm: add new extrinsic for asset transfers using explicit XCM transfer types (#3695) · 1e971b8d
      Adrian Catangiu authored
      
      
      # Description
      
      Add `transfer_assets_using()` for transferring assets from local chain
      to destination chain using explicit XCM transfer types such as:
      - `TransferType::LocalReserve`: transfer assets to sovereign account of
      destination chain and forward a notification XCM to `dest` to mint and
      deposit reserve-based assets to `beneficiary`.
      - `TransferType::DestinationReserve`: burn local assets and forward a
      notification to `dest` chain to withdraw the reserve assets from this
      chain's sovereign account and deposit them to `beneficiary`.
      - `TransferType::RemoteReserve(reserve)`: burn local assets, forward XCM
      to `reserve` chain to move reserves from this chain's SA to `dest`
      chain's SA, and forward another XCM to `dest` to mint and deposit
      reserve-based assets to `beneficiary`. Typically the remote `reserve` is
      Asset Hub.
      - `TransferType::Teleport`: burn local assets and forward XCM to `dest`
      chain to mint/teleport assets and deposit them to `beneficiary`.
      
      By default, an asset's reserve is its origin chain. But sometimes we may
      want to explicitly use another chain as reserve (as long as allowed by
      runtime `IsReserve` filter).
      
      This is very helpful for transferring assets with multiple configured
      reserves (such as Asset Hub ForeignAssets), when the transfer strictly
      depends on the used reserve.
      
      E.g. For transferring Foreign Assets over a bridge, Asset Hub must be
      used as the reserve location.
      
      # Example usage scenarios
      
      ## Transfer bridged ethereum ERC20-tokenX between ecosystem parachains.
      
      ERC20-tokenX is registered on AssetHub as a ForeignAsset by the
      Polkadot<>Ethereum bridge (Snowbridge). Its asset_id is something like
      `(parents:2, (GlobalConsensus(Ethereum), Address(tokenX_contract)))`.
      Its _original_ reserve is Ethereum (only we can't use Ethereum as a
      reserve in local transfers); but, since tokenX is also registered on
      AssetHub as a ForeignAsset, we can use AssetHub as a reserve.
      
      With this PR we can transfer tokenX from ParaA to ParaB while using
      AssetHub as a reserve.
      
      ## Transfer AssetHub ForeignAssets between parachains
      
      AssetA created on ParaA but also registered as foreign asset on Asset
      Hub. Can use AssetHub as a reserve.
      
      And all of the above can be done while still controlling transfer type
      for `fees` so mixing assets in same transfer is supported.
      
      # Tests
      
      Added integration tests for showcasing:
      - transferring local (not bridged) assets from parachain over bridge
      using local Asset Hub reserve,
      - transferring foreign assets from parachain to Asset Hub,
      - transferring foreign assets from Asset Hub to parachain,
      - transferring foreign assets from parachain to parachain using local
      Asset Hub reserve.
      
      ---------
      
      Co-authored-by: default avatarBranislav Kontur <[email protected]>
      Co-authored-by: command-bot <>
      1e971b8d
  3. Apr 04, 2024
    • Francisco Aguirre's avatar
      XCM builder pattern improvement - Accept `impl Into<T>` instead of just `T` (#3708) · c130ea99
      Francisco Aguirre authored
      
      
      The XCM builder pattern lets you build xcms like so:
      
      ```rust
      let xcm = Xcm::builder()
          .withdraw_asset((Parent, 100u128).into())
          .buy_execution((Parent, 1u128).into())
          .deposit_asset(All.into(), AccountId32 { id: [0u8; 32], network: None }.into())
          .build();
      ```
      
      All the `.into()` become quite annoying to have to write.
      I accepted `impl Into<T>` instead of `T` in the generated methods from
      the macro.
      Now the previous example can be simplified as follows:
      
      ```rust
      let xcm = Xcm::builder()
          .withdraw_asset((Parent, 100u128))
          .buy_execution((Parent, 1u128))
          .deposit_asset(All, [0u8; 32])
          .build();
      ```
      
      ---------
      
      Co-authored-by: default avatarBastian Köcher <[email protected]>
      Co-authored-by: command-bot <>
      Co-authored-by: default avatarAdrian Catangiu <[email protected]>
      c130ea99
  4. Apr 02, 2024
    • Dastan's avatar
      migrations: prevent accidentally using unversioned migrations instead of... · e5427969
      Dastan authored
      migrations: prevent accidentally using unversioned migrations instead of `VersionedMigration` (#3835)
      
      closes #1324 
      
      #### Problem
      Currently, it is possible to accidentally use inner unversioned
      migration instead of `VersionedMigration` since both implement
      `OnRuntimeUpgrade`.
      
      #### Solution
      
      With this change, we make it clear that value of `Inner` is not intended
      to be used directly. It is achieved by bounding `Inner` to new trait
      `UncheckedOnRuntimeUpgrade`, which has the same interface (except
      `unchecked_` prefix) as `OnRuntimeUpgrade`.
      
      #### `try-runtime` functions
      
      Since developers can implement `try-runtime` for `Inner` value in
      `VersionedMigration` and have custom logic for it, I added the same
      `try-runtime` functions to `UncheckedOnRuntimeUpgrade`. I looked for a
      ways to not duplicate functions, but couldn't find anything that doesn't
      significantly change the codebase. So I would appreciate If you have any
      suggestions to improve this
      
      cc @liamaharon
      
       @xlc 
      
      polkadot address: 16FqwPZ8GRC5U5D4Fu7W33nA55ZXzXGWHwmbnE1eT6pxuqcT
      
      ---------
      
      Co-authored-by: default avatarLiam Aharon <[email protected]>
      e5427969
    • Adrian Catangiu's avatar
      pallet-xcm: fix weights for all XTs and deprecate unlimited weight ones (#3927) · d0ebb850
      Adrian Catangiu authored
      
      
      Fix "double-weights" for extrinsics, use only the ones benchmarked in
      the runtime.
      
      Deprecate extrinsics that don't specify WeightLimit, remove their usage
      across the repo.
      
      ---------
      
      Signed-off-by: default avatarAdrian Catangiu <[email protected]>
      Co-authored-by: command-bot <>
      d0ebb850
  5. Mar 27, 2024
  6. Mar 26, 2024
    • Pavel Orlov's avatar
      XCM Fee Payment Runtime API (#3607) · 3c972fc1
      Pavel Orlov authored
      The PR provides API for obtaining:
      - the weight required to execute an XCM message,
      - a list of acceptable `AssetId`s for message execution payment,
      - the cost of the weight in the specified acceptable `AssetId`.
      
      It is meant to address an issue where one has to guess how much fee to
      pay for execution. Also, at the moment, a client has to guess which
      assets are acceptable for fee execution payment.
      See the related issue
      https://github.com/paritytech/polkadot-sdk/issues/690.
      With this API, a client is supposed to query the list of the supported
      asset IDs (in the XCM version format the client understands), weigh the
      XCM program the client wants to execute and convert the weight into one
      of the acceptable assets. Note that the client is supposed to know what
      program will be executed on what chains. However, having a small
      companion JS library for the pallet-xcm and xtokens should be enough to
      determine what XCM programs will be executed and where (since these
      pallets compose a known small set of programs).
      ```Rust
      pub trait XcmPaymentApi<Call>
      	where
      		Call: Codec,
      	{
      		/// Returns a list of acceptable payment assets.
      		///
      		/// # Arguments
      		///
      		/// * `xcm_version`: Version.
      		fn query_acceptable_payment_assets(xcm_version: Version) -> Result<Vec<VersionedAssetId>, Error>;
      		/// Returns a weight needed to execute a XCM.
      		///
      		/// # Arguments
      		///
      		/// * `message`: `VersionedXcm`.
      		fn query_xcm_weight(message: VersionedXcm<Call>) -> Result<Weight, Error>;
      		/// Converts a weight into a fee for the specified `AssetId`.
      		///
      		/// # Arguments
      		///
      		/// * `weight`: convertible `Weight`.
      		/// * `asset`: `VersionedAssetId`.
      		fn query_weight_to_asset_fee(weight: Weight, asset: VersionedAssetId) -> Result<u128, Error>;
      		/// Get delivery fees for sending a specific `message` to a `destination`.
      		/// These always come in a specific asset, defined by the chain.
      		///
      		/// # Arguments
      		/// * `message`: The message that'll be sent, necessary because most delivery fees are based on the
      		///   size of the message.
      		/// * `destination`: The destination to send the message to. Different destinations may use
      		///   different senders that charge different fees.
      		fn query_delivery_fees(destination: VersionedLocation, message: VersionedXcm<()>) -> Result<VersionedAssets, Error>;
      	}
      ```
      An
      [example](https://gist.github.com/PraetorP/4bc323ff85401abe253897ba990ec29d
      
      )
      of a client side code.
      
      ---------
      
      Co-authored-by: default avatarFrancisco Aguirre <[email protected]>
      Co-authored-by: default avatarAdrian Catangiu <[email protected]>
      Co-authored-by: default avatarDaniel Shiposha <[email protected]>
      3c972fc1
    • Dcompoze's avatar
      Fix spelling mistakes across the whole repository (#3808) · 002d9260
      Dcompoze authored
      **Update:** Pushed additional changes based on the review comments.
      
      **This pull request fixes various spelling mistakes in this
      repository.**
      
      Most of the changes are contained in the first **3** commits:
      
      - `Fix spelling mistakes in comments and docs`
      
      - `Fix spelling mistakes in test names`
      
      - `Fix spelling mistakes in error messages, panic messages, logs and
      tracing`
      
      Other source code spelling mistakes are separated into individual
      commits for easier reviewing:
      
      - `Fix the spelling of 'authority'`
      
      - `Fix the spelling of 'REASONABLE_HEADERS_IN_JUSTIFICATION_ANCESTRY'`
      
      - `Fix the spelling of 'prev_enqueud_messages'`
      
      - `Fix the spelling of 'endpoint'`
      
      - `Fix the spelling of 'children'`
      
      - `Fix the spelling of 'PenpalSiblingSovereignAccount'`
      
      - `Fix the spelling of 'PenpalSudoAccount'`
      
      - `Fix the spelling of 'insufficient'`
      
      - `Fix the spelling of 'PalletXcmExtrinsicsBenchmark'`
      
      - `Fix the spelling of 'subtracted'`
      
      - `Fix the spelling of 'CandidatePendingAvailability'`
      
      - `Fix the spelling of 'exclusive'`
      
      - `Fix the spelling of 'until'`
      
      - `Fix the spelling of 'discriminator'`
      
      - `Fix the spelling of 'nonexistent'`
      
      - `Fix the spelling of 'subsystem'`
      
      - `Fix the spelling of 'indices'`
      
      - `Fix the spelling of 'committed'`
      
      - `Fix the spelling of 'topology'`
      
      - `Fix the spelling of 'response'`
      
      - `Fix the spelling of 'beneficiary'`
      
      - `Fix the spelling of 'formatted'`
      
      - `Fix the spelling of 'UNKNOWN_PROOF_REQUEST'`
      
      - `Fix the spelling of 'succeeded'`
      
      - `Fix the spelling of 'reopened'`
      
      - `Fix the spelling of 'proposer'`
      
      - `Fix the spelling of 'InstantiationNonce'`
      
      - `Fix the spelling of 'depositor'`
      
      - `Fix the spelling of 'expiration'`
      
      - `Fix the spelling of 'phantom'`
      
      - `Fix the spelling of 'AggregatedKeyValue'`
      
      - `Fix the spelling of 'randomness'`
      
      - `Fix the spelling of 'defendant'`
      
      - `Fix the spelling of 'AquaticMammal'`
      
      - `Fix the spelling of 'transactions'`
      
      - `Fix the spelling of 'PassingTracingSubscriber'`
      
      - `Fix the spelling of 'TxSignaturePayload'`
      
      - `Fix the spelling of 'versioning'`
      
      - `Fix the spelling of 'descendant'`
      
      - `Fix the spelling of 'overridden'`
      
      - `Fix the spelling of 'network'`
      
      Let me know if this structure is adequate.
      
      **Note:** The usage of the words `Merkle`, `Merkelize`, `Merklization`,
      `Merkelization`, `Merkleization`, is somewhat inconsistent but I left it
      as it is.
      
      ~~**Note:** In some places the term `Receival` is used to refer to
      message reception, IMO `Reception` is the correct word here, but I left
      it as it is.~~
      
      ~~**Note:** In some places the term `Overlayed` is used instead of the
      more acceptable version `Overlaid` but I also left it as it is.~~
      
      ~~**Note:** In some places the term `Applyable` is used instead of the
      correct version `Applicable` but I also left it as it is.~~
      
      **Note:** Some usage of British vs American english e.g. `judgement` vs
      `judgment`, `initialise` vs `initialize`, `optimise` vs `optimize` etc.
      are both present in different places, but I suppose that's
      understandable given the number of contributors.
      
      ~~**Note:** There is a spelling mistake in `.github/CODEOWNERS` but it
      triggers errors in CI when I make changes to it, so I left it as it
      is.~~
      002d9260
  7. Mar 22, 2024
  8. Mar 19, 2024
    • Juan Ignacio Rios's avatar
      Add HRMP notification handlers to the xcm-executor (#3696) · 8b3bf39a
      Juan Ignacio Rios authored
      Currently the xcm-executor returns an `Unimplemented` error if it
      receives any HRMP-related instruction.
      What I propose here, which is what we are currently doing in our forked
      executor at polimec, is to introduce a trait implemented by the executor
      which will handle those instructions.
      
      This way, if parachains want to keep the default behavior, they just use
      `()` and it will return unimplemented, but they can also implement their
      own logic to establish HRMP channels with other chains in an automated
      fashion, without requiring to go through governance.
      
      Our implementation is mentioned in the [polkadot HRMP
      docs](https://arc.net/l/quote/hduiivbu
      
      ), and it was suggested to us to
      submit a PR to add these changes to polkadot-sdk.
      
      ---------
      
      Co-authored-by: default avatarBranislav Kontur <[email protected]>
      Co-authored-by: command-bot <>
      8b3bf39a
  9. Mar 15, 2024
  10. Mar 01, 2024
  11. Feb 26, 2024
  12. Feb 19, 2024
    • PG Herveou's avatar
      Contracts: xcm host fn fixes (#3086) · ca382f32
      PG Herveou authored
      ## Xcm changes:
      - Fix `pallet_xcm::execute`, move the logic into The `ExecuteController`
      so it can be shared with anything that implement that trait.
      - Make `ExecuteController::execute` retursn `DispatchErrorWithPostInfo`
      instead of `DispatchError`, so that we don't charge the full
      `max_weight` provided if the execution is incomplete (useful for
      force_batch or contracts calls)
      - Fix docstring for `pallet_xcm::execute`, to reflect the changes from
      #2405
      - Update the signature for `ExecuteController::execute`, we don't need
      to return the `Outcome` anymore since we only care about
      `Outcome::Complete`
      
      ## Contracts changes:
      
      - Update host fn `xcm_exexute`, we don't need to write the `Outcome` to
      the sandbox memory anymore. This was also not charged as well before so
      it if fixes this too.
      - One of the issue was that the dry_run of a contract that call
      `xcm_execute` would exhaust the `gas_limit`.
      
      This is because `XcmExecuteController::execute` takes a `max_weight`
      argument, and since we don't want the user to specify it manually we
      were passing everything left by pre-charghing
      `ctx.ext.gas_meter().gas_left()`
      
      - To fix it I added a `fn influence_lowest_limit` on the `Token` trait
      and make it return false for `RuntimeCost::XcmExecute`.
      - Got rid of the `RuntimeToken` indirection, we can just use
      `RuntimeCost` directly.
      
      ---------
      
      Co-authored-by: command-bot <>
      ca382f32
  13. Feb 13, 2024
  14. Feb 06, 2024
  15. Jan 31, 2024
    • Branislav Kontur's avatar
      [frame] `#[pallet::composite_enum]` improved variant count handling + removed... · bb8ddc46
      Branislav Kontur authored
      [frame] `#[pallet::composite_enum]` improved variant count handling + removed `pallet_balances`'s `MaxHolds` config (#2657)
      
      I started this investigation/issue based on @liamaharon question
      [here](https://github.com/paritytech/polkadot-sdk/pull/1801#discussion_r1410452499).
      
      ## Problem
      
      The `pallet_balances` integrity test should correctly detect that the
      runtime has correct distinct `HoldReasons` variant count. I assume the
      same situation exists for RuntimeFreezeReason.
      
      It is not a critical problem, if we set `MaxHolds` with a sufficiently
      large value, everything should be ok. However, in this case, the
      integrity_test check becomes less useful.
      
      **Situation for "any" runtime:**
      - `HoldReason` enums from different pallets:
      ```rust
              /// from pallet_nis
              #[pallet::composite_enum]
      	pub enum HoldReason {
      		NftReceipt,
      	}
      
              /// from pallet_preimage
              #[pallet::composite_enum]
      	pub enum HoldReason {
      		Preimage,
      	}
      
              // from pallet_state-trie-migration
              #[pallet::composite_enum]
      	pub enum HoldReason {
      		SlashForContinueMigrate,
      		SlashForMigrateCustomTop,
      		SlashForMigrateCustomChild,
      	}
      ```
      
      - generated `RuntimeHoldReason` enum looks like:
      ```rust
      pub enum RuntimeHoldReason {
      
          #[codec(index = 32u8)]
          Preimage(pallet_preimage::HoldReason),
      
          #[codec(index = 38u8)]
          Nis(pallet_nis::HoldReason),
      
          #[codec(index = 42u8)]
          StateTrieMigration(pallet_state_trie_migration::HoldReason),
      }
      ```
      
      - composite enum `RuntimeHoldReason` variant count is detected as `3`
      - we set `type MaxHolds = ConstU32<3>`
      - `pallet_balances::integrity_test` is ok with `3`(at least 3)
      
      However, the real problem can occur in a live runtime where some
      functionality might stop working. This is due to a total of 5 distinct
      hold reasons (for pallets with multi-instance support, it is even more),
      and not all of them can be used because of an incorrect `MaxHolds`,
      which is deemed acceptable according to the `integrity_test`:
        ```
        // pseudo-code - if we try to call all of these:
      
      T::Currency::hold(&pallet_nis::HoldReason::NftReceipt.into(),
      &nft_owner, deposit)?;
      T::Currency::hold(&pallet_preimage::HoldReason::Preimage.into(),
      &nft_owner, deposit)?;
      
      T::Currency::hold(&pallet_state_trie_migration::HoldReason::SlashForContinueMigrate.into(),
      &nft_owner, deposit)?;
      
        // With `type MaxHolds = ConstU32<3>` these two will fail
      
      T::Currency::hold(&pallet_state_trie_migration::HoldReason::SlashForMigrateCustomTop.into(),
      &nft_owner, deposit)?;
      
      T::Currency::hold(&pallet_state_trie_migration::HoldReason::SlashForMigrateCustomChild.into(),
      &nft_owner, deposit)?;
        ```  
      
      
      ## Solutions
      
      A macro `#[pallet::*]` expansion is extended of `VariantCount`
      implementation for the `#[pallet::composite_enum]` enum type. This
      expansion generates the `VariantCount` implementation for pallets'
      `HoldReason`, `FreezeReason`, `LockId`, and `SlashReason`. Enum variants
      must be plain enum values without fields to ensure a deterministic
      count.
      
      The composite runtime enum, `RuntimeHoldReason` and
      `RuntimeFreezeReason`, now sets `VariantCount::VARIANT_COUNT` as the sum
      of pallets' enum `VariantCount::VARIANT_COUNT`:
      ```rust
      #[frame_support::pallet(dev_mode)]
      mod module_single_instance {
      
      	#[pallet::composite_enum]
      	pub enum HoldReason {
      		ModuleSingleInstanceReason1,
      		ModuleSingleInstanceReason2,
      	}
      ...
      }
      
      #[frame_support::pallet(dev_mode)]
      mod module_multi_instance {
      
      	#[pallet::composite_enum]
      	pub enum HoldReason<I: 'static = ()> {
      		ModuleMultiInstanceReason1,
      		ModuleMultiInstanceReason2,
      		ModuleMultiInstanceReason3,
      	}
      ...
      }
      
      
      impl self::sp_api_hidden_includes_construct_runtime::hidden_include::traits::VariantCount
          for RuntimeHoldReason
      {
          const VARIANT_COUNT: u32 = 0
              + module_single_instance::HoldReason::VARIANT_COUNT
              + module_multi_instance::HoldReason::<module_multi_instance::Instance1>::VARIANT_COUNT
              + module_multi_instance::HoldReason::<module_multi_instance::Instance2>::VARIANT_COUNT
              + module_multi_instance::HoldReason::<module_multi_instance::Instance3>::VARIANT_COUNT;
      }
      ```
      
      In addition, `MaxHolds` is removed (as suggested
      [here](https://github.com/paritytech/polkadot-sdk/pull/2657#discussion_r1443324573))
      from `pallet_balances`, and its `Holds` are now bounded to
      `RuntimeHoldReason::VARIANT_COUNT`. Therefore, there is no need to let
      the runtime specify `MaxHolds`.
      
      
      ## For reviewers
      
      Relevant changes can be found here:
      - `substrate/frame/support/procedural/src/lib.rs` 
      -  `substrate/frame/support/procedural/src/pallet/parse/composite.rs`
      -  `substrate/frame/support/procedural/src/pallet/expand/composite.rs`
      -
      `substrate/frame/support/procedural/src/construct_runtime/expand/composite_helper.rs`
      -
      `substrate/frame/support/procedural/src/construct_runtime/expand/hold_reason.rs`
      -
      `substrate/frame/support/procedural/src/construct_runtime/expand/freeze_reason.rs`
      - `substrate/frame/support/src/traits/misc.rs`
      
      And the rest of the files is just about removed `MaxHolds` from
      `pallet_balances`
      
      ## Next steps
      
      Do the same for `MaxFreezes`
      https://github.com/paritytech/polkadot-sdk/issues/2997
      
      .
      
      ---------
      
      Co-authored-by: command-bot <>
      Co-authored-by: default avatarBastian Köcher <[email protected]>
      Co-authored-by: default avatarDónal Murray <[email protected]>
      Co-authored-by: default avatargupnik <[email protected]>
      bb8ddc46
  16. Jan 24, 2024
  17. Jan 22, 2024
  18. Jan 16, 2024
    • Francisco Aguirre's avatar
      XCMv4 (#1230) · 8428f678
      Francisco Aguirre authored
      
      
      # Note for reviewer
      
      Most changes are just syntax changes necessary for the new version.
      Most important files should be the ones under the `xcm` folder.
      
      # Description 
      
      Added XCMv4.
      
      ## Removed `Multi` prefix
      The following types have been renamed:
      - MultiLocation -> Location
      - MultiAsset -> Asset
      - MultiAssets -> Assets
      - InteriorMultiLocation -> InteriorLocation
      - MultiAssetFilter -> AssetFilter
      - VersionedMultiAsset -> VersionedAsset
      - WildMultiAsset -> WildAsset
      - VersionedMultiLocation -> VersionedLocation
      
      In order to fix a name conflict, the `Assets` in `xcm-executor` were
      renamed to `HoldingAssets`, as they represent assets in holding.
      
      ## Removed `Abstract` asset id
      
      It was not being used anywhere and this simplifies the code.
      
      Now assets are just constructed as follows:
      
      ```rust
      let asset: Asset = (AssetId(Location::new(1, Here)), 100u128).into();
      ```
      
      No need for specifying `Concrete` anymore.
      
      ## Outcome is now a named fields struct
      
      Instead of
      
      ```rust
      pub enum Outcome {
        Complete(Weight),
        Incomplete(Weight, Error),
        Error(Error),
      }
      ```
      
      we now have
      
      ```rust
      pub enum Outcome {
        Complete { used: Weight },
        Incomplete { used: Weight, error: Error },
        Error { error: Error },
      }
      ```
      
      ## Added Reanchorable trait
      
      Now both locations and assets implement this trait, making it easier to
      reanchor both.
      
      ## New syntax for building locations and junctions
      
      Now junctions are built using the following methods:
      
      ```rust
      let location = Location {
          parents: 1,
          interior: [Parachain(1000), PalletInstance(50), GeneralIndex(1984)].into()
      };
      ```
      
      or
      
      ```rust
      let location = Location::new(1, [Parachain(1000), PalletInstance(50), GeneralIndex(1984)]);
      ```
      
      And they are matched like so:
      
      ```rust
      match location.unpack() {
        (1, [Parachain(id)]) => ...
        (0, Here) => ...,
        (1, [_]) => ...,
      }
      ```
      
      This syntax is mandatory in v4, and has been also implemented for v2 and
      v3 for easier migration.
      
      This was needed to make all sizes smaller.
      
      # TODO
      - [x] Scaffold v4
      - [x] Port github.com/paritytech/polkadot/pull/7236
      - [x] Remove `Multi` prefix
      - [x] Remove `Abstract` asset id
      
      ---------
      
      Co-authored-by: command-bot <>
      Co-authored-by: default avatarKeith Yeung <[email protected]>
      8428f678
  19. Dec 18, 2023
  20. Dec 14, 2023
    • Francisco Aguirre's avatar
      Add FungibleAdapter (#2684) · 10a91f82
      Francisco Aguirre authored
      In the move from the old `Currency` traits to the new `fungible/s`
      family of traits, we already had the `FungiblesAdapter` and
      `NonFungiblesAdapter` for multiple fungible and non fungible assets
      respectively. However, for handling only one fungible asset, we were
      missing a `FungibleAdapter`, and so used the old `CurrencyAdapter`
      instead. This PR aims to fill in that gap, and provide the new adapter
      for more updated examples.
      
      I marked the old `CurrencyAdapter` as deprecated as part of this PR, and
      I'll change it to the new `FungibleAdapter` in a following PR.
      The two stages are separated so as to not bloat this PR with some name
      fixes in tests.
      
      ---------
      
      Co-authored-by: command-bot <>
      10a91f82
  21. Dec 12, 2023
    • Branislav Kontur's avatar
      Ensure xcm versions over bridge (on sending chains) (#2481) · 575b8f8d
      Branislav Kontur authored
      ## Summary
      
      This pull request proposes a solution for improved control of the
      versioned XCM flow over the bridge (across different consensus chains)
      and resolves the situation where the sending chain/consensus has already
      migrated to a higher XCM version than the receiving chain/consensus.
      
      ## Problem/Motivation
      
      The current flow over the bridge involves a transfer from AssetHubRococo
      (AHR) to BridgeHubRococo (BHR) to BridgeHubWestend (BHW) and finally to
      AssetHubWestend (AHW), beginning with a reserve-backed transfer on AHR.
      
      In this process:
      1. AHR sends XCM `ExportMessage` through `XcmpQueue`, incorporating XCM
      version checks using the `WrapVersion` feature, influenced by
      `pallet_xcm::SupportedVersion` (managed by
      `pallet_xcm::force_xcm_version` or version discovery).
      
      2. BHR handles the `ExportMessage` instruction, utilizing the latest XCM
      version. The `HaulBlobExporter` converts the inner XCM to
      [`VersionedXcm::from`](https://github.com/paritytech/polkadot-sdk/blob/63ac2471aa0210f0ac9903bdd7d8f9351f9a635f/polkadot/xcm/xcm-builder/src/universal_exports.rs#L465-L467),
      also using the latest XCM version.
      
      However, challenges arise:
      - Incompatibility when BHW uses a different version than BHR. For
      instance, if BHR migrates to **XCMv4** while BHW remains on **XCMv3**,
      BHR's `VersionedXcm::from` uses `VersionedXcm::V4` variant, causing
      encoding issues for BHW.
        ```
      	/// Just a simulation of possible error, which could happen on BHW
      	/// (this code is based on actual master without XCMv4)
      	let encoded = hex_literal::hex!("0400");
      	println!("{:?}", VersionedXcm::<()>::decode(&mut &encoded[..]));
      
      Err(Error { cause: None, desc: "Could not decode `VersionedXcm`, variant
      doesn't exist" })
        ``` 
      - Similar compatibility issues exist between AHR and AHW.
      
      ## Solution
      
      This pull request introduces the following solutions:
      
      1. **New trait `CheckVersion`** - added to the `xcm` module and exposing
      `pallet_xcm::SupportedVersion`. This enhancement allows checking the
      actual XCM version for desired destinations outside of the `pallet_xcm`
      module.
      
      2. **Version Check in `HaulBlobExporter`** uses `CheckVersion` to check
      known/configured destination versions, ensuring compatibility. For
      example, in the scenario mentioned, BHR can store the version `3` for
      BHW. If BHR is on XCMv4, it will attempt to downgrade the message to
      version `3` instead of using the latest version `4`.
      
      3. **Version Check in `pallet-xcm-bridge-hub-router`** - this check
      ensures compatibility with the real destination's XCM version,
      preventing the unnecessary sending of messages to the local bridge hub
      if versions are incompatible.
      
      These additions aim to improve the control and compatibility of XCM
      flows over the bridge and addressing issues related to version
      mismatches.
      
      ## Possible alternative solution
      
      _(More investigation is needed, and at the very least, it should extend
      to XCMv4/5. If this proves to be a viable option, I can open an RFC for
      XCM.)._
      
      Add the `XcmVersion` attribute to the `ExportMessage` so that the
      sending chain can determine, based on what is stored in
      `pallet_xcm::SupportedVersion`, the version the destination is using.
      This way, we may not need to handle the version in `HaulBlobExporter`.
      
      ```
      ExportMessage {
      	network: NetworkId,
      	destination: InteriorMultiLocation,
      	xcm: Xcm<()>
      	destination_xcm_version: Version, // <- new attritbute
      },
      ```
      
      ```
      pub trait ExportXcm {
              fn validate(
      		network: NetworkId,
      		channel: u32,
      		universal_source: &mut Option<InteriorMultiLocation>,
      		destination: &mut Option<InteriorMultiLocation>,
      		message: &mut Option<Xcm<()>>,
                      destination_xcm_version: Version, , // <- new attritbute
      	) -> SendResult<Self::Ticket>;
      ```
      
      ## Future Directions
      
      This PR does not fix version discovery over bridge, further
      investigation will be conducted here:
      https://github.com/paritytech/polkadot-sdk/issues/2417.
      
      ## TODO
      
      - [x] `pallet_xcm` mock for tests uses hard-coded XCM version `2` -
      change to 3 or lastest?
      - [x] fix `pallet-xcm-bridge-hub-router`
      - [x] fix HaulBlobExporter with version determination
      [here](https://github.com/paritytech/polkadot-sdk/blob/2183669d05f9b510f979a0cc3c7847707bacba2e/polkadot/xcm/xcm-builder/src/universal_exports.rs#L465)
      - [x] add unit-tests to the runtimes
      - [x] run benchmarks for `ExportMessage`
      - [x] extend local run scripts about `force_xcm_version(dest, version)`
      - [ ] when merged, prepare governance calls for Rococo/Westend
      - [ ] add PRDoc
      
      Part of: https://github.com/paritytech/parity-bridges-common/issues/2719
      
      ---------
      
      Co-authored-by: command-bot <>
      575b8f8d
  22. Dec 11, 2023
  23. Dec 06, 2023
    • Adrian Catangiu's avatar
      pallet-xcm: add new flexible `transfer_assets()` call/extrinsic (#2388) · e7651cf4
      Adrian Catangiu authored
      # Motivation (+testing)
      
      ### Enable easy `ForeignAssets` transfers using `pallet-xcm` 
      
      We had just previously added capabilities to teleport fees during
      reserve-based transfers, but what about reserve-transferring fees when
      needing to teleport some non-fee asset?
      
      This PR aligns everything under either explicit reserve-transfer,
      explicit teleport, or this new flexible `transfer_assets()` which can
      mix and match as needed with fewer artificial constraints imposed to the
      user.
      
      This will enable, for example, a (non-system) parachain to teleport
      their `ForeignAssets` assets to AssetHub while using DOT to pay fees.
      (the assets are teleported - as foreign assets should from their owner
      chain - while DOT used for fees can only be reserve-based transferred
      between said parachain and AssetHub).
      
      Added `xcm-emulator` tests for this scenario ^.
      
      # Description
      
      Reverts `(limited_)reserve_transfer_assets` to only allow reserve-based
      transfers for all `assets` including fees.
      
      Similarly `(limited_)teleport_assets` only allows teleports for all
      `assets` including fees.
          
      For complex combinations of asset transfers where assets and fees may
      have different reserves or different reserve/teleport trust
      configurations, users can use the newly added `transfer_assets()`
      extrinsic which is more flexible in allowing more complex scenarios.
      
      `assets` (excluding `fees`) must have same reserve location or otherwise
      be teleportable to `dest`.
      No limitations imposed on `fees`.
      
      - for local reserve: transfer assets to sovereign account of destination
      chain and forward a notification XCM to `dest` to mint and deposit
      reserve-based assets to `beneficiary`.
      - for destination reserve: burn local assets and forward a notification
      to `dest` chain to withdraw the reserve assets from this chain's
      sovereign account and deposit them to `beneficiary`.
      - for remote reserve: burn local assets, forward XCM to reserve chain to
      move reserves from this chain's SA to `dest` chain's SA, and forward
      another XCM to `dest` to mint and deposit reserve-based assets to
      `beneficiary`.
      - for teleports: burn local assets and forward XCM to `dest` chain to
      mint/teleport assets and deposit them to `beneficiary`.
      
      ## Review notes
      
      Only around 500 lines are prod code (see `pallet_xcm/src/lib.rs`), the
      rest of the PR is new tests and improving existing tests.
      
      ---------
      
      Co-authored-by: command-bot <>
      e7651cf4
  24. Nov 28, 2023
  25. Nov 24, 2023
  26. Nov 15, 2023
  27. Nov 13, 2023
    • Adrian Catangiu's avatar
      pallet-xcm: enhance `reserve_transfer_assets` to support remote reserves (#1672) · 18257373
      Adrian Catangiu authored
      ## Motivation
      
      `pallet-xcm` is the main user-facing interface for XCM functionality,
      including assets manipulation functions like `teleportAssets()` and
      `reserve_transfer_assets()` calls.
      
      While `teleportAsset()` works both ways, `reserve_transfer_assets()`
      works only for sending reserve-based assets to a remote destination and
      beneficiary when the reserve is the _local chain_.
      
      ## Solution
      
      This PR enhances `pallet_xcm::(limited_)reserve_withdraw_assets` to
      support transfers when reserves are other chains.
      This will allow complete, **bi-directional** reserve-based asset
      transfers user stories using `pallet-xcm`.
      
      Enables following scenarios:
      - transferring assets with local reserve (was previously supported iff
      asset used as fee also had local reserve - now it works in all cases),
      - transferring assets with reserve on destination,
      - transferring assets with reserve on remote/third-party chain (iff
      assets and fees have same remote reserve),
      - transferring assets with reserve different than the reserve of the
      asset to be used as fees - meaning can be used to transfer random asset
      with local/dest reserve while using DOT for fees on all involved chains,
      even if DOT local/dest reserve doesn't match asset reserve,
      - transferring assets with any type of local/dest reserve while using
      fees which can be teleported between involved chains.
      
      All of the above is done by pallet inner logic without the user having
      to specify which scenario/reserves/teleports/etc. The correct scenario
      and corresponding XCM programs are identified, and respectively, built
      automatically based on runtime configuration of trusted teleporters and
      trusted reserves.
      
      #### Current limitations:
      - while `fees` and "non-fee" `assets` CAN have different reserves (or
      fees CAN be teleported), the remaining "non-fee" `assets` CANNOT, among
      themselves, have different reserve locations (this is also implicitly
      enforced by `MAX_ASSETS_FOR_TRANSFER=2`, but this can be safely
      increased in the future).
      - `fees` and "non-fee" `assets` CANNOT have **different remote**
      reserves (this could also be supported in the future, but adds even more
      complexity while possibly not being worth it - we'll see what the future
      holds).
      
      Fixes https://github.com/paritytech/polkadot-sdk/issues/1584
      Fixes https://github.com/paritytech/polkadot-sdk/issues/2055
      
      
      
      ---------
      
      Co-authored-by: default avatarFrancisco Aguirre <[email protected]>
      Co-authored-by: default avatarBranislav Kontur <[email protected]>
      18257373
  28. Nov 10, 2023
    • PG Herveou's avatar
      Contracts: Add XCM traits to interface with contracts (#2086) · 6b7be115
      PG Herveou authored
      We are introducing a new set of `XcmController` traits (final name yet
      to be determined).
      These traits are implemented by `pallet-xcm` and allows other pallets,
      such as `pallet_contracts`, to rely on these traits instead of tight
      coupling them to `pallet-xcm`.
      
      Using only the existing Xcm traits would mean duplicating the logic from
      `pallet-xcm` in these other pallets, which we aim to avoid. Our
      objective is to ensure that when these APIs are called from
      `pallet-contracts`, they produce the exact same outcomes as if called
      directly from `pallet-xcm`.
      
      The other benefits is that we can also expose return values to
      `pallet-contracts` instead of just calling `pallet-xcm` dispatchable and
      getting a `DispatchResult` back.
      
      See traits integration in this PR
      https://github.com/paritytech/polkadot-sdk/pull/1248
      
      , where the traits
      are used as follow to define and implement `pallet-contracts` Config.
      ```rs
      // Contracts config:
      pub trait Config: frame_system::Config {
        // ...
      
        /// A type that exposes XCM APIs, allowing contracts to interact with other parachains, and
        /// execute XCM programs.
        type Xcm: xcm_executor::traits::Controller<
      	  OriginFor<Self>,
      	  <Self as frame_system::Config>::RuntimeCall,
      	  BlockNumberFor<Self>,
        >;
      }
      
      // implementation
      impl pallet_contracts::Config for Runtime {
              // ...
      
      	type Xcm = pallet_xcm::Pallet<Self>;
      }
      ```
      
      ---------
      
      Co-authored-by: default avatarAlexander Theißen <[email protected]>
      Co-authored-by: command-bot <>
      6b7be115
    • Liam Aharon's avatar
      Improve `VersionedMigration` naming conventions (#2264) · 84ddbaf6
      Liam Aharon authored
      As suggested by @ggwpez
      (https://github.com/paritytech/polkadot-sdk/pull/2142#discussion_r1388145872),
      remove the `VersionChecked` prefix from version checked migrations (but
      leave `VersionUnchecked` prefixes)
      
      ---------
      
      Co-authored-by: command-bot <>
      84ddbaf6
  29. Nov 01, 2023
  30. Oct 24, 2023
  31. Oct 18, 2023
    • Keith Yeung's avatar
      Introduce XcmFeesToAccount fee manager (#1234) · 3dece311
      Keith Yeung authored
      
      
      Combination of paritytech/polkadot#7005, its addon PR
      paritytech/polkadot#7585 and its companion paritytech/cumulus#2433.
      
      This PR introduces a new XcmFeesToAccount struct which implements the
      `FeeManager` trait, and assigns this struct as the `FeeManager` in the
      XCM config for all runtimes.
      
      The struct simply deposits all fees handled by the XCM executor to a
      specified account. In all runtimes, the specified account is configured
      as the treasury account.
      
      XCM __delivery__ fees are now being introduced (unless the root origin
      is sending a message to a system parachain on behalf of the originating
      chain).
      
      # Note for reviewers
      
      Most file changes are tests that had to be modified to account for the
      new fees.
      Main changes are in:
      - cumulus/pallets/xcmp-queue/src/lib.rs <- To make it track the delivery
      fees exponential factor
      - polkadot/xcm/xcm-builder/src/fee_handling.rs <- Added. Has the
      FeeManager implementation
      - All runtime xcm_config files <- To add the FeeManager to the XCM
      configuration
      
      # Important note
      
      After this change, instructions that create and send a new XCM (Query*,
      Report*, ExportMessage, InitiateReserveWithdraw, InitiateTeleport,
      DepositReserveAsset, TransferReserveAsset, LockAsset and RequestUnlock)
      will require the corresponding origin account in the origin register to
      pay for transport delivery fees, and the onward message will fail to be
      sent if the origin account does not have the required amount. This
      delivery fee is on top of what we already collect as tx fees in
      pallet-xcm and XCM BuyExecution fees!
      
      Wallet UIs that want to expose the new delivery fee can do so using the
      formula:
      
      ```
      delivery_fee_factor * (base_fee + encoded_msg_len * per_byte_fee)
      ```
      
      where the delivery fee factor can be obtained from the corresponding
      pallet based on which transport you are using (UMP, HRMP or bridges),
      the base fee is a constant, the encoded message length from the message
      itself and the per byte fee is the same as the configured per byte fee
      for txs (i.e. `TransactionByteFee`).
      
      ---------
      
      Co-authored-by: default avatarBranislav Kontur <[email protected]>
      Co-authored-by: default avatarjoe petrowski <[email protected]>
      Co-authored-by: default avatarGiles Cope <[email protected]>
      Co-authored-by: command-bot <>
      Co-authored-by: default avatarFrancisco Aguirre <[email protected]>
      Co-authored-by: default avatarLiam Aharon <[email protected]>
      Co-authored-by: default avatarKian Paimani <[email protected]>
      3dece311
  32. Sep 25, 2023
  33. Sep 20, 2023
    • Gavin Wood's avatar
      XCM: Deprecate old functions (#1645) · e7d29bc3
      Gavin Wood authored
      Two old functions should be deprecated and have their code altered in
      line with capabilities of XCMv2 and above.
      
      This means we can use the proper `Unlimited` form of weight limit rather
      than guessing weight from the local chain.
      e7d29bc3
  34. Sep 13, 2023
    • Liam Aharon's avatar
      Stabilize `VersionedMigration` (#1503) · 72de70c7
      Liam Aharon authored
      `VersionedMigration` has become somewhat widely used for handling
      version bumps in migrations the last few months.
      
      It is currently behind the `experimental` feature flag, requiring every
      pallet that writes a new migration with version bumps to set up the
      `experimental` flag in their own Cargo.tomls, and also for every runtime
      using these pallets to explicitly enable the `experimental` flag for
      each pallet.
      
      This is becoming quite verbose, and I can only see the number of pallets
      requiring the experimental flag increasing for no other reason than
      using what has become a commonly used feature.
      
      Additionally, I'm writing migration docs and would like to avoid
      stepping through how to use the `experimental` feature to get
      `VersionedMigration` working.
      
      Since the feature has been used in production for some time now without
      any reported issues, is becoming commonly used and ready to advertise in
      docs, I feel this is a good time to make it non-experimental.
      72de70c7
  35. Aug 31, 2023
    • Bastian Köcher's avatar
      Rename `polkadot-parachain` to `polkadot-parachain-primitives` (#1334) · a33d7922
      Bastian Köcher authored
      * Rename `polkadot-parachain` to `polkadot-parachain-primitives`
      
      While doing this it also fixes some last `rustdoc` issues and fixes
      another Cargo warning related to `pallet-paged-list`.
      
      * Fix compilation
      
      * ".git/.scripts/commands/fmt/fmt.sh"
      
      * Fix XCM docs
      
      ---------
      
      Co-authored-by: command-bot <>
      a33d7922