# 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: Keith Yeung <[email protected]>

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 <[email protected]>
Co-authored-by: Liam Aharon <[email protected]>

- Updates all safe call filters to allow `system::authorize_upgrade`.
- Updates Coretime safe call filter to allow `sudo` and
`system_set_storage`.
- Update Coretime teleports to allow teleportation with other system
chains.

---------

Co-authored-by: Bastian Köcher <[email protected]>

Adds the `authorize_upgrade` -> `enact_authorized_upgrade` pattern to
`frame-system`. This will be useful for upgrading bridged chains that
are under the governance of Polkadot without passing entire runtime Wasm
blobs over a bridge.

Notes:

- Changed `enact_authorized_upgrade` to `apply_authorized_upgrade`.
Personal opinion, "apply" more accurately expresses what it's doing. Can
change back if outvoted.
- Remove `check_version` in favor of two extrinsics, so as to make
_checked_ the default.
- Left calls in `parachain-system` and marked as deprecated to prevent
breaking the API. They just call into the `frame-system` functions.
- Updated `frame-system` benchmarks to v2 syntax.

---------

Co-authored-by: command-bot <>

closes https://github.com/paritytech/polkadot-sdk/issues/1842

Decoupling Pallet from the Concept of Native Currency

Currently, the pallet is intrinsically linked with the concept of native
currency, requiring users to provide implementations of the
`fungible::*` and `fungibles::*` traits to interact with native and non
native assets. This incapsulates some non-related to the pallet
complexity and makes it less adaptable in contexts where the native
currency concept is absent.

With this PR, the dependence on `fungible::*` for liquidity-supplying
assets has been removed. Instead, the native and non-native currencies'
handling is now overseen by a single type that implements the
`fungibles::*` traits. To simplify this integration, types have been
introduced to facilitate the creation of a union between `fungible::*`
and `fungibles::*` implementations, producing a unified `fungibles::*`
type.

One of the reasons driving these changes is the ambition to create a
more user-friendly API for the `SwapCredit` implementation. Given that
it interacts with two distinct credit types from `fungible` and
`fungibles`, a unified type was introduced. Clients now manage potential
conversion failures for those credit types. In certain contexts, it's
vital to guarantee that operations are fail-safe, like in this impl -
[PR](https://github.com/paritytech/polkadot-sdk/pull/1845), place in
[code](https://github.com/paritytech/polkadot-sdk/blob/20b85a5f

/cumulus/primitives/utility/src/lib.rs#L429).

Additional Updates:
- abstracted the pool ID and its account derivation logic via trait
bounds, along with common implementation offerings;
- removed `inc_providers` on a pool creation for the pool account;
- benchmarks:
-- swap complexity is N, not const;
-- removed `From<u128> + Into<u128>` bound from `T::Balance`;
-- removed swap/liquidity/.. amount constants, resolve them dynamically
based on pallet configuration;
-- migrated to v2 API;
- `OnUnbalanced` handler for the pool creation fee, replacing direct
transfers to a specified account ID;
- renamed `MultiAssetId` to `AssetKind` aligning with naming across
frame crates;

related PRs:
- (depends) https://github.com/paritytech/polkadot-sdk/pull/1677
- (caused) https://github.com/paritytech/polkadot-sdk/pull/2033
- (caused) https://github.com/paritytech/polkadot-sdk/pull/1876

---------

Co-authored-by: joe petrowski <[email protected]>
Co-authored-by: Liam Aharon <[email protected]>

Introduces a swap implementation that allows the exchange of a credit
(aka Negative Imbalance) of one asset for a credit of another asset.

This is particularly useful when a credit swap is required but may not
have sufficient value to meet the ED constraint, hence cannot be
deposited to temp account before. An example use case is when XCM fees
are paid using an asset held in the XCM executor registry and has to be
swapped for native currency.

Additional Updates:
- encapsulates the existing `Swap` trait impl within a transactional
context, since partial storage mutation is possible when an error
occurs;
- supplied `Currency` and `Assets` impls must be implemented over the
same `Balance` type, the `AssetBalance` generic type is dropped. This
helps to avoid numerous type conversion and overflow cases. If those
types are different it should be handled outside of the pallet;
- `Box` asset kind on a pallet level, unbox on a runtime level - here
[why](https://substrate.stackexchange.com/questions/10039/boxed-argument-of-a-dispatchable/10103#10103);
- `path` uses `Vec` now, instead of `BoundedVec` since it is never used
in PoV;
- removes the `Transfer` event due to it's redundancy with the events
emitted by `fungible/s` implementations;
- modifies the `SwapExecuted` event type;

related issue: 
- https://github.com/paritytech/polkadot-sdk/issues/105

related PRs:
- (required for) https://github.com/paritytech/polkadot-sdk/pull/1845
- (caused) https://github.com/paritytech/polkadot-sdk/pull/1717

// DONE make the pallet work only with `fungibles` trait and make it
free from the concept of a `native` asset -
https://github.com/paritytech/polkadot-sdk/issues/1842

---------

Co-authored-by: joe petrowski <[email protected]>

This PR contains just a few clippy fixes and nits, which are, however,
relaxed by workspace clippy settings here:
https://github.com/paritytech/polkadot-sdk/blob/master/Cargo.toml#L483-L506

---------

Co-authored-by: Dmitry Sinyavin <[email protected]>
Co-authored-by: ordian <[email protected]>
Co-authored-by: command-bot <>
Co-authored-by: Bastian Köcher <[email protected]>

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 <>

This PR backports `transaction_version` bump from `1.5.0` release back
to `master`

We currently use a bit of a hack in `.cargo/config` to make sure that
clippy isn't too annoying by specifying the list of lints.

There is now a stable way to define lints for a workspace. The only down
side is that every crate seems to have to opt into this so there's a
*few* files modified in this PR.

Dependencies:

- [x] PR that upgrades CI to use rust 1.74 is merged.

---------

Co-authored-by: joe petrowski <[email protected]>
Co-authored-by: Branislav Kontur <[email protected]>
Co-authored-by: Liam Aharon <[email protected]>

Co-authored-by: command-bot <>

## 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/63ac2471/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/2183669d/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 <>

This PR introduces a script and some templates to use the prdoc involved
in a release and build:
- the changelog
- a simple draft of audience documentation

Since the prdoc presence was enforced in the middle of the version
1.5.0, not all PRs did come with a `prdoc` file.
This PR creates all the missing `prdoc` files with some minimum content
allowing to properly generate the changelog.
The generated content is **not** suitable for the audience
documentation.

The audience documentation will be possible with the next version, when
all PR come with a proper `prdoc`.

## Assumptions

- the prdoc files for release `vX.Y.Z` have been moved under
`prdoc/X.Y.Z`
- the changelog requires for now for the prdoc files to contain author +
topic. Thos fields are optional.

The build script can  be called as:
```
VERSION=X.Y.Z ./scripts/release/build-changelogs.sh
```

Related:
-  #1408

---------

Co-authored-by: EgorPopelyaev <[email protected]>

Treasury Pallet Instance for the Fellowship in Westend Collectives.

In this update, we present a Treasury Pallet Instance that is under the
control of the Fellowship body, with oversight from the Root and
Treasurer origins. Here's how it is governed:
- the Root origin have the authority to reject or approve spend
proposals, with no amount limit for approvals.
- the Treasurer origin have the authority to reject or approve spend
proposals, with approval limits of up to 10,000,000 DOT.
- Voice of all Fellows ranked at 3 or above can reject or approve spend
proposals, with a maximum approval limit of 10,000 DOT.
- Voice of Fellows ranked at 4 or above can also reject or approve spend
proposals, with a maximum approval limit of 10,000,000 DOT.

Additionally, we introduce the Asset Rate Pallet Instance to establish
conversion rates from asset A to B. This is used to determine if a
proposed spend amount involving a non-native asset is permissible by the
commanding origin. The rates can be set up by the Root, Treasurer
origins, or Voice of all Fellows.

---------

Co-authored-by: joe petrowski <[email protected]>
Co-authored-by: joepetrowski <[email protected]>

As suggested in this thread:
https://github.com/polkadot-fellows/runtimes/pull/87#discussion_r1400237122

We already have the `IsChildSystemParachain`, which may be used at relay
chain, but it can't be used at a parachain level. So let's use
`AllSiblingSystemParachains` for that. I was thinking about
`AllSystemParachains`, but it may cause wrong impression that it can be
used at a relay chain level.

---------

Co-authored-by: joe petrowski <[email protected]>

# 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 <>

Removes obsolete fields from the `QueueConfigData` structure. For the
remaining fields, if they use the old defaults, we replace them with the
new defaults.

Resolves: https://github.com/paritytech/polkadot-sdk/issues/1795

Using taplo, fixes all our broken and inconsistent toml formatting and
adds CI to keep them tidy.

If people want we can customise the format rules as described here
https://taplo.tamasfe.dev/configuration/formatter-options.html

@ggwpez

, I suggest zepter is used only for checking features are
propagated, and leave formatting for taplo to avoid duplicate work and
conflicts.

TODO
- [x] Use `exclude = [...]` syntax in taplo file to ignore zombienet
tests instead of deleting the dir

---------

Signed-off-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>

Westend SP dmp queue pallet removal is complete.

<img width="1499" alt="Screenshot 2023-11-28 at 08 31 27"
src="https://github.com/paritytech/polkadot-sdk/assets/16665596/906246fb-3de9-4133-a827-431636a097ad">

<img width="1499" alt="Screenshot 2023-11-28 at 08 32 08"
src="https://github.com/paritytech/polkadot-sdk/assets/16665596/bde84891-b044-42c7-9a0b-59125cd24db1">

<img width="1499" alt="Screenshot 2023-11-28 at 08 31 45"
src="https://github.com/paritytech/polkadot-sdk/assets/16665596/38337484-0856-45c0-b9ff-8c785bc3c0e3">

## Overview

This PR aligns the `spec_version` formatting to the [recent
changes](https://github.com/polkadot-fellows/runtimes/pull/26/files#diff-efa4caeb17487ecb13d8f5eb7863c3241d84afa2e73fbf25909a2ca89df0f362R142)
made for the Polkadot/Kusama runtimes.

It also backports the latest version `v1.4.0` bumps as `1_004_000`.

## Details

During the switch from `v0.9` to `v1.x`, the format of the
`spec_version` was modified from: `(M)m_ppp` for a runtime considered on
version `M.m.pp`. For instance `0.9.42` had a `spec_version` of `9420`.

With the transition to `v1.x`, the format was changed to a bigger number
(still `u32`) formatted as `MM_mm_ppp` where `1.2.3` would be stored as
`01_02_003`.

This PR aligns the format with that has been introduced in the
fellowship repo: `MMM_mmm_ppp`.

---------

Co-authored-by: Bastian Köcher <[email protected]>

This PR fixes two things:
- relax `force_default_xcm_version` for testnet system parachains (e.g.
BridgeHubWestend has now 2 and there is no way to change it to 3, so we
need to call `force_xcm_version(3)` for every parachain that it is
connected to, because we send XCMv3 messages)
- add `Storage` item to `PolkadotXcm` pallet definition (now we cannot
see storage items for `pallet_xcm` in PJS)


## TODO

- [ ] when merged open PR to `polkadot-fellows/runtimes` repo

Fix some incorrect doc-comments

Missed in https://github.com/paritytech/polkadot-sdk/pull/1672

Fixes https://github.com/paritytech/polkadot-sdk/issues/106

Port of cumulus PR https://github.com/paritytech/cumulus/pull/2960

This PR adds the ability to bid for collator slots even after the max
number of collators have already registered. This eliminates the first
come, first served mechanism that was in place before.

Key changes:
- added `update_bond` extrinsic to allow registered candidates to adjust
their bonds in order to dynamically control their bids
- added `take_candidate_slot` extrinsic to try to replace an already
existing candidate by bidding more than them
- candidates are now kept in a sorted list in the pallet storage, where
the top `DesiredCandidates` out of `MaxCandidates` candidates in the
list will be selected by the session pallet as collators
- if the candidacy bond is increased through a `set_candidacy_bond`
call, candidates which don't meet the new bond requirements are kicked


# Checklist

- [ ] My PR includes a detailed description as outlined in the
"Description" section above
- [ ] My PR follows the [labeling
requirements](https://github.com/paritytech/polkadot-sdk/blob/master/docs/CONTRIBUTING.md#process)
of this project (at minimum one label for `T` required)
- [ ] I have made corresponding changes to the documentation (if
applicable)
- [ ] I have added tests that prove my fix is effective or that my
feature works (if applicable)
- [ ] If this PR alters any external APIs or interfaces used by
Polkadot, the corresponding Polkadot PR is ready as well as the
corresponding Cumulus PR (optional)

---------

Signed-off-by: georgepisaltu <[email protected]>

Closes https://github.com/paritytech/polkadot-sdk/issues/2241

See issue comments for more details about this storage.

## 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: Francisco Aguirre <[email protected]>
Co-authored-by: Branislav Kontur <[email protected]>

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: Alexander Theißen <[email protected]>
Co-authored-by: command-bot <>

Right now governance could only control byte-fee component of Rococo <>
Westend message fees (paid at Asset Hubs). This PR changes it a bit:
1) governance now allowed to control both fee components - byte fee and
base fee;
2) base fee now includes cost of "default" delivery and confirmation
transactions, in addition to `ExportMessage` instruction cost.

(imported from https://github.com/paritytech/cumulus/pull/2157)

## Changes

This MR refactores the XCMP, Parachains System and DMP pallets to use
the [MessageQueue](https://github.com/paritytech/substrate/pull/12485)
for delayed execution of incoming messages. The DMP pallet is entirely
replaced by the MQ and thereby removed. This allows for PoV-bounded
execution and resolves a number of issues that stem from the current
work-around.

All System Parachains adopt this change.  
The most important changes are in `primitives/core/src/lib.rs`,
`parachains/common/src/process_xcm_message.rs`,
`pallets/parachain-system/src/lib.rs`, `pallets/xcmp-queue/src/lib.rs`
and the runtime configs.

### DMP Queue Pallet

The pallet got removed and its logic refactored into parachain-system.
Overweight message management can be done directly through the MQ
pallet.

Final undeployment migrations are provided by
`cumulus_pallet_dmp_queue::UndeployDmpQueue` and `DeleteDmpQueue` that
can be configured with an aux config trait like:

```rust
parameter_types! {
	pub const DmpQueuePalletName: &'static str = \"DmpQueue\" < CHANGE ME;
	pub const RelayOrigin: AggregateMessageOrigin = AggregateMessageOrigin::Parent;
}

impl cumulus_pallet_dmp_queue::MigrationConfig for Runtime {
	type PalletName = DmpQueuePalletName;
	type DmpHandler = frame_support::traits::EnqueueWithOrigin<MessageQueue, RelayOrigin>;
	type DbWeight = <Runtime as frame_system::Config>::DbWeight;
}

// And adding them to your Migrations tuple:
pub type Migrations = (
	...
	cumulus_pallet_dmp_queue::UndeployDmpQueue<Runtime>,
	cumulus_pallet_dmp_queue::DeleteDmpQueue<Runtime>,
);
```

### XCMP Queue pallet

Removed all dispatch queue functionality. Incoming XCMP messages are now
either: Immediately handled if they are Signals, enqueued into the MQ
pallet otherwise.

New config items for the XCMP queue pallet:
```rust
/// The actual queue implementation that retains the messages for later processing.
type XcmpQueue: EnqueueMessage<ParaId>;

/// How a XCM over HRMP from a sibling parachain should be processed.
type XcmpProcessor: ProcessMessage<Origin = ParaId>;

/// The maximal number of suspended XCMP channels at the same time.
#[pallet::constant]
type MaxInboundSuspended: Get<u32>;
```

How to configure those:

```rust
// Use the MessageQueue pallet to store messages for later processing. The `TransformOrigin` is needed since
// the MQ pallet itself operators on `AggregateMessageOrigin` but we want to enqueue `ParaId`s.
type XcmpQueue = TransformOrigin<MessageQueue, AggregateMessageOrigin, ParaId, ParaIdToSibling>;

// Process XCMP messages from siblings. This is type-safe to only accept `ParaId`s. They will be dispatched
// with origin `Junction::Sibling(…)`.
type XcmpProcessor = ProcessFromSibling<
	ProcessXcmMessage<
		AggregateMessageOrigin,
		xcm_executor::XcmExecutor<xcm_config::XcmConfig>,
		RuntimeCall,
	>,
>;

// Not really important what to choose here. Just something larger than the maximal number of channels.
type MaxInboundSuspended = sp_core::ConstU32<1_000>;
```

The `InboundXcmpStatus` storage item was replaced by
`InboundXcmpSuspended` since it now only tracks inbound queue suspension
and no message indices anymore.

Now only sends the most recent channel `Signals`, as all prio ones are
out-dated anyway.

### Parachain System pallet

For `DMP` messages instead of forwarding them to the `DMP` pallet, it
now pushes them to the configured `DmpQueue`. The message processing
which was triggered in `set_validation_data` is now being done by the MQ
pallet `on_initialize`.

XCMP messages are still handed off to the `XcmpMessageHandler`
(XCMP-Queue pallet) - no change here.

New config items for the parachain system pallet:
```rust
/// Queues inbound downward messages for delayed processing. 
///
/// Analogous to the `XcmpQueue` of the XCMP queue pallet.
type DmpQueue: EnqueueMessage<AggregateMessageOrigin>;
``` 

How to configure:
```rust
/// Use the MQ pallet to store DMP messages for delayed processing.
type DmpQueue = MessageQueue;
``` 

## Message Flow

The flow of messages on the parachain side. Messages come in from the
left via the `Validation Data` and finally end up at the `Xcm Executor`
on the right.

![Untitled
(1)](https://github.com/paritytech/cumulus/assets/10380170/6cf8b377-88c9-4aed-96df-baace266e04d)

## Further changes

- Bumped the default suspension, drop and resume thresholds in
`QueueConfigData::default()`.
- `XcmpQueue::{suspend_xcm_execution, resume_xcm_execution}` errors when
they would be a noop.
- Properly validate the `QueueConfigData` before setting it.
- Marked weight files as auto-generated so they wont auto-expand in the
MR files view.
- Move the `hypothetical` asserts to `frame_support` under the name
`experimental_hypothetically`

Questions:
- [ ] What about the ugly `#[cfg(feature = \"runtime-benchmarks\")]` in
the runtimes? Not sure how to best fix. Just having them like this makes
tests fail that rely on the real message processor when the feature is
enabled.
- [ ] Need a good weight for `MessageQueueServiceWeight`. The scheduler
already takes 80% so I put it to 10% but that is quite low.

TODO:
- [x] Remove c&p code after
https://github.com/paritytech/polkadot/pull/6271
- [x] Use `HandleMessage` once it is public in Substrate
- [x] fix `runtime-benchmarks` feature
https://github.com/paritytech/polkadot/pull/6966
- [x] Benchmarks
- [x] Tests
- [ ] Migrate `InboundXcmpStatus` to `InboundXcmpSuspended`
- [x] Possibly cleanup Migrations (DMP+XCMP)
- [x] optional: create `TransformProcessMessageOrigin` in Substrate and
replace `ProcessFromSibling`
- [ ] Rerun weights on ref HW

---------

Signed-off-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Liam Aharon <[email protected]>
Co-authored-by: joe petrowski <[email protected]>
Co-authored-by: Kian Paimani <[email protected]>
Co-authored-by: command-bot <>

## Summary

Asset bridging support for AssetHub**Rococo** <-> AssetHub**Wococo** was
added [here](https://github.com/paritytech/polkadot-sdk/pull/1215), so
now we aim to bridge AssetHub**Rococo** and AssetHub**Westend**. (And
perhaps retire AssetHubWococo and the Wococo chains).

## Solution

**bridge-hub-westend-runtime**
- added new runtime as a copy of `bridge-hub-rococo-runtime`
- added support for bridging to `BridgeHubRococo`
- added tests and benchmarks

**bridge-hub-rococo-runtime**
- added support for bridging to `BridgeHubWestend`
- added tests and benchmarks
- internal refactoring by splitting bridge configuration per network,
e.g., `bridge_to_whatevernetwork_config.rs`.

**asset-hub-rococo-runtime**
- added support for asset bridging to `AssetHubWestend` (allows to
receive only WNDs)
- added new xcm router for `Westend`
- added tests and benchmarks

**asset-hub-westend-runtime**
- added support for asset bridging to `AssetHubRococo` (allows to
receive only ROCs)
- added new xcm router for `Rococo`
- added tests and benchmarks

## Deployment

All changes will be deployed as a part of
https://github.com/paritytech/polkadot-sdk/issues/1988.

## TODO

- [x] benchmarks for all pallet instances
- [x] integration tests
- [x] local run scripts


Relates to:
https://github.com/paritytech/parity-bridges-common/issues/2602
Relates to: https://github.com/paritytech/polkadot-sdk/issues/1988

---------

Co-authored-by: command-bot <>
Co-authored-by: Adrian Catangiu <[email protected]>
Co-authored-by: joe petrowski <[email protected]>

Co-authored-by: Sergejs Kostjucenko <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>

Closes https://github.com/paritytech/release-engineering/issues/6

Adds a new Github Workflow which on a new release being created, builds
and attaches all runtimes managed in this repository in two flavours:
- `dev-debug-build`: Built with the `try-runtime` feature and has
logging enabled
- `on-chain-release`: Built with the regular old `on-chain-release`
feature

The new Github Workflow could be extended in the future by the
@paritytech/release-engineering team to fully automate the release
process if they choose to, similar to how it is fully automated in the
Fellowship repo
(https://github.com/polkadot-fellows/runtimes/blob/main/.github/workflows/release.yml).

The `on-chain-release` did not exist for parachains, so I added it. 

---

Tested on my fork: 
- https://github.com/liamaharon/polkadot-sdk/actions/runs/6663773523
- https://github.com/liamaharon/polkadot-sdk/releases/tag/test-6

---------

Co-authored-by: Chevdor <[email protected]>
Co-authored-by: Dónal Murray <[email protected]>

# Description

- What does this PR do?

While working with `pallet_nfts` through `nonfungibles_v2` traits
`Inspect, Mutate`, I found out that once you have set the collection
attribute with `<Nfts as Mutate>::set_collection_attribute()`, it's not
possible to read it with `<Nfts as Inspect>::collection_attribute()`
since they use different `namespace` values. When setting the attribute,
`AttributeNamespace::Pallet` is used, while
`AttributeNamespace::CollectionOwner` is used when reading.

more context:
https://github.com/freeverseio/laos/issues/7#issuecomment-1766137370

This PR makes `item` an optional parameter in
`Inspect::system_attribute()`, to be able to read collection attributes.

- Why are these changes needed?

To be able to read collection level attributes when reading attributes
of the collection. It will be possible to read collection attributes by
passing `None` for `item`

- How were these changes implemented and what do they affect?

`NftsApi` is also affected and `NftsApi::system_attribute()` now accepts
optional `item` parameter.

## Breaking change

Because of the change in the `NftsApi::system_attribute()` method's
`item` param, parachains who integrated the `NftsApi` need to update
their API code and frontend integrations accordingly. AssetHubs are
unaffected since the NftsApi wasn't released on those parachains yet.

[testnet] Align testnet system parachain runtimes using `RelayTreasuryLocation` and `SystemParachains` in the same way (#2023)

This PR addresses several issues:
- simplify referencing `RelayTreasuryLocation` without needing
additional `RelayTreasury` struct
- fix for referencing `SystemParachains` from parachain with `parents:
1` instead of `parents: 0`
- removed hard-coded constants and fix tests for `asset-hub-rococo`
which was merged to master after
https://github.com/paritytech/polkadot-sdk/pull/1726

---------

Co-authored-by: command-bot <>

Adds a config file that allows to run `zepter` without any arguments in
the workspace to address all issues.
A secondary workflow for the CI is provided as `zepter run check`. Both
the formatting and linting are now in one check for efficiancy.

The latest version also detects some more things that `featalign` was
already showing.

Error message [in the
CI](https://gitlab.parity.io/parity/mirrors/polkadot-sdk/-/jobs/3916205)
now looks like this:
```pre
...
crate 'test-parachains' (/Users/vados/Documents/work/polkadot-sdk/polkadot/parachain/test-parachains/Cargo.toml)
  feature 'std'
    must propagate to:
      parity-scale-codec
Found 55 issues (run with --fix to fix).
Error: Command 'lint propagate-feature' failed with exit code 1

Polkadot-SDK uses the Zepter CLI to detect abnormalities in the feature configuration.
It looks like one more more checks failed; please check the console output. You can try to automatically address them by running `zepter`.
Otherwise please ask directly in the Merge Request, GitHub Discussions or on Matrix Chat, thank you.

For more information, see:
  - https://github.com/paritytech/polkadot-sdk/issues/1831
  - https://github.com/ggwpez/zepter
```

TODO:
- [x] Check that CI fails correctly

---------

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

closes https://github.com/paritytech/polkadot-sdk/issues/1882

## Breaking Changes

This PR introduces a new item to `pallet_balances::Config`:

```diff
trait Config {
++    type RuntimeFreezeReasons;
}
```

This value is only used to check it against `type MaxFreeze`. A similar
check has been added for `MaxHolds` against `RuntimeHoldReasons`, which
is already given to `pallet_balances`.

In all contexts, you should pass the real `RuntimeFreezeReasons`
generated by `construct_runtime` to `type RuntimeFreezeReasons`. Passing
`()` would also work, but it would imply that the runtime uses no
freezes at all.

---------

Signed-off-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Oliver Tale-Yazdi <[email protected]>

## Problem

This PR addresses the issue with testnet AssetHub builds, which was
discovered during the execution of `bot bench`.

https://gitlab.parity.io/parity/mirrors/polkadot-sdk/-/jobs/4038738
```
     Compiling asset-hub-rococo-runtime-wasm v1.0.0 (/builds/parity/mirrors/polkadot-sdk/target/production/wbuild/asset-hub-rococo-runtime)
  warning: Linking globals named 'Core_version': symbol multiply defined!
  error: failed to load bitcode of module "rococo_runtime-8799ee884447805a.rococo_runtime.0bc572b8-cgu.0.rcgu.o": 
  warning: `asset-hub-rococo-runtime-wasm` (lib) generated 1 warning
  error: could not compile `asset-hub-rococo-runtime-wasm` (lib) due to previous error; 1 warning emitted
```

https://gitlab.parity.io/parity/mirrors/polkadot-sdk/-/jobs/4038739
```
Compiling asset-hub-westend-runtime-wasm v1.0.0 (/builds/parity/mirrors/polkadot-sdk/target/production/wbuild/asset-hub-westend-runtime)
  warning: Linking globals named 'Core_version': symbol multiply defined!
  error: failed to load bitcode of module "westend_runtime-86d7844430f97d5c.westend_runtime.b7678d03-cgu.0.rcgu.o": 
  warning: `asset-hub-westend-runtime-wasm` (lib) generated 1 warning
  error: could not compile `asset-hub-westend-runtime-wasm` (lib) due to previous error; 1 warning emitted
```

## Solution

- Removed dependencies on `rococo-runtime` and `westend-runtime`
introduced by [this
PR](https://github.com/paritytech/polkadot-sdk/pull/1234/files#diff-a86375df98e04ca3cce1ea35c40257a222e2d5087f5f528ff33307678b78dc2dR534-R550).
- Replaced `<rococo_runtime::Treasury as PalletInfoAccess>::index()`
with `rococo_runtime_constants::TREASURY_PALLET_ID`.
- Added `check_treasury_pallet_id` to the relay runtimes to ensure that
the constant is aligned with the pallet id.
- Added "Rococo Treasury" to the waived locations (that will not be
charged fees in the executor) for `BridgeHubRococo` (to be aligned with
AssetHubs).

## References

[Full element discussion
here](https://matrix.to/#/!JUeaZUiYbdrvzvtwSL:parity.io/$2PnjYMsWRjR7M3oOfGuRI0XkjdoqJLtRcAPVcDLuLVg?via=parity.io&via=web3.foundation).

---------

Co-authored-by: command-bot <>

The `xcm` crate was renamed to `staging-xcm` to be able to publish it to
crates.io as someone as squatted `xcm`. The problem with this rename is
that the `TypeInfo` includes the crate name which ultimately lands in
the metadata. The metadata is consumed by downstream users like
`polkadot-js` or people building on top of `polkadot-js`. These people
are using the entire `path` to find the type in the type registry. Thus,
their code would break as the type path would now be [`staging_xcm`,
`VersionedXcm`] instead of [`xcm`, `VersionedXcm`]. This pull request
fixes this by renaming the path segment `staging_xcm` to `xcm`.

This requires: https://github.com/paritytech/scale-info/pull/197

---------

Co-authored-by: Francisco Aguirre <[email protected]>