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// Copyright (C) Parity Technologies (UK) Ltd.
// This file is part of Polkadot.
// Polkadot is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Polkadot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Polkadot. If not, see <http://www.gnu.org/licenses/>.
//! XCM `Location` datatype.
use super::{traits::Reanchorable, Junction, Junctions};
use crate::{v3::MultiLocation as OldLocation, VersionedLocation};
use codec::{Decode, Encode, MaxEncodedLen};
use core::result;
use scale_info::TypeInfo;
/// A relative path between state-bearing consensus systems.
///
/// A location in a consensus system is defined as an *isolatable state machine* held within global
/// consensus. The location in question need not have a sophisticated consensus algorithm of its
/// own; a single account within Ethereum, for example, could be considered a location.
///
/// A very-much non-exhaustive list of types of location include:
/// - A (normal, layer-1) block chain, e.g. the Bitcoin mainnet or a parachain.
/// - A layer-0 super-chain, e.g. the Polkadot Relay chain.
/// - A layer-2 smart contract, e.g. an ERC-20 on Ethereum.
/// - A logical functional component of a chain, e.g. a single instance of a pallet on a Frame-based
/// Substrate chain.
/// - An account.
///
/// A `Location` is a *relative identifier*, meaning that it can only be used to define the
/// relative path between two locations, and cannot generally be used to refer to a location
/// universally. It is comprised of an integer number of parents specifying the number of times to
/// "escape" upwards into the containing consensus system and then a number of *junctions*, each
/// diving down and specifying some interior portion of state (which may be considered a
/// "sub-consensus" system).
///
/// This specific `Location` implementation uses a `Junctions` datatype which is a Rust `enum`
/// in order to make pattern matching easier. There are occasions where it is important to ensure
/// that a value is strictly an interior location, in those cases, `Junctions` may be used.
///
/// The `Location` value of `Null` simply refers to the interpreting consensus system.
#[derive(
Clone,
Decode,
Encode,
Eq,
PartialEq,
Ord,
PartialOrd,
Debug,
TypeInfo,
MaxEncodedLen,
serde::Serialize,
serde::Deserialize,
)]
pub struct Location {
/// The number of parent junctions at the beginning of this `Location`.
pub parents: u8,
/// The interior (i.e. non-parent) junctions that this `Location` contains.
pub interior: Junctions,
}
impl Default for Location {
fn default() -> Self {
Self { parents: 0, interior: Junctions::Here }
}
}
/// A relative location which is constrained to be an interior location of the context.
///
/// See also `Location`.
pub type InteriorLocation = Junctions;
impl Location {
/// Creates a new `Location` with the given number of parents and interior junctions.
pub fn new(parents: u8, interior: impl Into<Junctions>) -> Location {
Location { parents, interior: interior.into() }
}
/// Consume `self` and return the equivalent `VersionedLocation` value.
pub const fn into_versioned(self) -> VersionedLocation {
VersionedLocation::V4(self)
}
/// Creates a new `Location` with 0 parents and a `Here` interior.
///
/// The resulting `Location` can be interpreted as the "current consensus system".
pub const fn here() -> Location {
Location { parents: 0, interior: Junctions::Here }
}
/// Creates a new `Location` which evaluates to the parent context.
pub const fn parent() -> Location {
Location { parents: 1, interior: Junctions::Here }
}
/// Creates a new `Location` with `parents` and an empty (`Here`) interior.
pub const fn ancestor(parents: u8) -> Location {
Location { parents, interior: Junctions::Here }
}
/// Whether the `Location` has no parents and has a `Here` interior.
pub fn is_here(&self) -> bool {
self.parents == 0 && self.interior.len() == 0
}
/// Remove the `NetworkId` value in any interior `Junction`s.
pub fn remove_network_id(&mut self) {
self.interior.remove_network_id();
}
/// Return a reference to the interior field.
pub fn interior(&self) -> &Junctions {
&self.interior
}
/// Return a mutable reference to the interior field.
pub fn interior_mut(&mut self) -> &mut Junctions {
&mut self.interior
}
/// Returns the number of `Parent` junctions at the beginning of `self`.
pub const fn parent_count(&self) -> u8 {
self.parents
}
/// Returns the parent count and the interior [`Junctions`] as a tuple.
///
/// To be used when pattern matching, for example:
///
/// ```rust
/// # use staging_xcm::v4::{Junctions::*, Junction::*, Location};
/// fn get_parachain_id(loc: &Location) -> Option<u32> {
/// match loc.unpack() {
/// (0, [Parachain(id)]) => Some(*id),
/// _ => None
/// }
/// }
/// ```
pub fn unpack(&self) -> (u8, &[Junction]) {
(self.parents, self.interior.as_slice())
}
/// Returns boolean indicating whether `self` contains only the specified amount of
/// parents and no interior junctions.
pub const fn contains_parents_only(&self, count: u8) -> bool {
matches!(self.interior, Junctions::Here) && self.parents == count
}
/// Returns the number of parents and junctions in `self`.
pub fn len(&self) -> usize {
self.parent_count() as usize + self.interior.len()
}
/// Returns the first interior junction, or `None` if the location is empty or contains only
/// parents.
pub fn first_interior(&self) -> Option<&Junction> {
self.interior.first()
}
/// Returns last junction, or `None` if the location is empty or contains only parents.
pub fn last(&self) -> Option<&Junction> {
self.interior.last()
}
/// Splits off the first interior junction, returning the remaining suffix (first item in tuple)
/// and the first element (second item in tuple) or `None` if it was empty.
pub fn split_first_interior(self) -> (Location, Option<Junction>) {
let Location { parents, interior: junctions } = self;
let (suffix, first) = junctions.split_first();
let location = Location { parents, interior: suffix };
(location, first)
}
/// Splits off the last interior junction, returning the remaining prefix (first item in tuple)
/// and the last element (second item in tuple) or `None` if it was empty or if `self` only
/// contains parents.
pub fn split_last_interior(self) -> (Location, Option<Junction>) {
let Location { parents, interior: junctions } = self;
let (prefix, last) = junctions.split_last();
let location = Location { parents, interior: prefix };
(location, last)
}
/// Mutates `self`, suffixing its interior junctions with `new`. Returns `Err` with `new` in
/// case of overflow.
pub fn push_interior(&mut self, new: impl Into<Junction>) -> result::Result<(), Junction> {
self.interior.push(new)
}
/// Mutates `self`, prefixing its interior junctions with `new`. Returns `Err` with `new` in
/// case of overflow.
pub fn push_front_interior(
&mut self,
new: impl Into<Junction>,
) -> result::Result<(), Junction> {
self.interior.push_front(new)
}
/// Consumes `self` and returns a `Location` suffixed with `new`, or an `Err` with
/// the original value of `self` in case of overflow.
pub fn pushed_with_interior(
self,
new: impl Into<Junction>,
) -> result::Result<Self, (Self, Junction)> {
match self.interior.pushed_with(new) {
Ok(i) => Ok(Location { interior: i, parents: self.parents }),
Err((i, j)) => Err((Location { interior: i, parents: self.parents }, j)),
}
}
/// Consumes `self` and returns a `Location` prefixed with `new`, or an `Err` with the
/// original value of `self` in case of overflow.
pub fn pushed_front_with_interior(
self,
new: impl Into<Junction>,
) -> result::Result<Self, (Self, Junction)> {
match self.interior.pushed_front_with(new) {
Ok(i) => Ok(Location { interior: i, parents: self.parents }),
Err((i, j)) => Err((Location { interior: i, parents: self.parents }, j)),
}
}
/// Returns the junction at index `i`, or `None` if the location is a parent or if the location
/// does not contain that many elements.
pub fn at(&self, i: usize) -> Option<&Junction> {
let num_parents = self.parents as usize;
if i < num_parents {
return None
}
self.interior.at(i - num_parents)
}
/// Returns a mutable reference to the junction at index `i`, or `None` if the location is a
/// parent or if it doesn't contain that many elements.
pub fn at_mut(&mut self, i: usize) -> Option<&mut Junction> {
let num_parents = self.parents as usize;
if i < num_parents {
return None
}
self.interior.at_mut(i - num_parents)
}
/// Decrements the parent count by 1.
pub fn dec_parent(&mut self) {
self.parents = self.parents.saturating_sub(1);
}
/// Removes the first interior junction from `self`, returning it
/// (or `None` if it was empty or if `self` contains only parents).
pub fn take_first_interior(&mut self) -> Option<Junction> {
self.interior.take_first()
}
/// Removes the last element from `interior`, returning it (or `None` if it was empty or if
/// `self` only contains parents).
pub fn take_last(&mut self) -> Option<Junction> {
self.interior.take_last()
}
/// Ensures that `self` has the same number of parents as `prefix`, its junctions begins with
/// the junctions of `prefix` and that it has a single `Junction` item following.
/// If so, returns a reference to this `Junction` item.
///
/// # Example
/// ```rust
/// # use staging_xcm::v4::{Junctions::*, Junction::*, Location};
/// # fn main() {
/// let mut m = Location::new(1, [PalletInstance(3), OnlyChild]);
/// assert_eq!(
/// m.match_and_split(&Location::new(1, [PalletInstance(3)])),
/// Some(&OnlyChild),
/// );
/// assert_eq!(m.match_and_split(&Location::new(1, Here)), None);
/// # }
/// ```
pub fn match_and_split(&self, prefix: &Location) -> Option<&Junction> {
if self.parents != prefix.parents {
return None
}
self.interior.match_and_split(&prefix.interior)
}
pub fn starts_with(&self, prefix: &Location) -> bool {
self.parents == prefix.parents && self.interior.starts_with(&prefix.interior)
}
/// Mutate `self` so that it is suffixed with `suffix`.
///
/// Does not modify `self` and returns `Err` with `suffix` in case of overflow.
///
/// # Example
/// ```rust
/// # use staging_xcm::v4::{Junctions::*, Junction::*, Location, Parent};
/// # fn main() {
/// let mut m: Location = (Parent, Parachain(21), 69u64).into();
/// assert_eq!(m.append_with((Parent, PalletInstance(3))), Ok(()));
/// assert_eq!(m, Location::new(1, [Parachain(21), PalletInstance(3)]));
/// # }
/// ```
pub fn append_with(&mut self, suffix: impl Into<Self>) -> Result<(), Self> {
let prefix = core::mem::replace(self, suffix.into());
match self.prepend_with(prefix) {
Ok(()) => Ok(()),
Err(prefix) => Err(core::mem::replace(self, prefix)),
}
}
/// Consume `self` and return its value suffixed with `suffix`.
///
/// Returns `Err` with the original value of `self` and `suffix` in case of overflow.
///
/// # Example
/// ```rust
/// # use staging_xcm::v4::{Junctions::*, Junction::*, Location, Parent};
/// # fn main() {
/// let mut m: Location = (Parent, Parachain(21), 69u64).into();
/// let r = m.appended_with((Parent, PalletInstance(3))).unwrap();
/// assert_eq!(r, Location::new(1, [Parachain(21), PalletInstance(3)]));
/// # }
/// ```
pub fn appended_with(mut self, suffix: impl Into<Self>) -> Result<Self, (Self, Self)> {
match self.append_with(suffix) {
Ok(()) => Ok(self),
Err(suffix) => Err((self, suffix)),
}
}
/// Mutate `self` so that it is prefixed with `prefix`.
///
/// Does not modify `self` and returns `Err` with `prefix` in case of overflow.
///
/// # Example
/// ```rust
/// # use staging_xcm::v4::{Junctions::*, Junction::*, Location, Parent};
/// # fn main() {
/// let mut m: Location = (Parent, Parent, PalletInstance(3)).into();
/// assert_eq!(m.prepend_with((Parent, Parachain(21), OnlyChild)), Ok(()));
/// assert_eq!(m, Location::new(1, [PalletInstance(3)]));
/// # }
/// ```
pub fn prepend_with(&mut self, prefix: impl Into<Self>) -> Result<(), Self> {
// prefix self (suffix)
// P .. P I .. I p .. p i .. i
let mut prefix = prefix.into();
let prepend_interior = prefix.interior.len().saturating_sub(self.parents as usize);
let final_interior = self.interior.len().saturating_add(prepend_interior);
if final_interior > super::junctions::MAX_JUNCTIONS {
return Err(prefix)
}
let suffix_parents = (self.parents as usize).saturating_sub(prefix.interior.len());
let final_parents = (prefix.parents as usize).saturating_add(suffix_parents);
if final_parents > 255 {
return Err(prefix)
}
// cancel out the final item on the prefix interior for one of the suffix's parents.
while self.parents > 0 && prefix.take_last().is_some() {
self.dec_parent();
}
// now we have either removed all suffix's parents or prefix interior.
// this means we can combine the prefix's and suffix's remaining parents/interior since
// we know that with at least one empty, the overall order will be respected:
// prefix self (suffix)
// P .. P (I) p .. p i .. i => P + p .. (no I) i
// -- or --
// P .. P I .. I (p) i .. i => P (no p) .. I + i
self.parents = self.parents.saturating_add(prefix.parents);
for j in prefix.interior.into_iter().rev() {
self.push_front_interior(j)
.expect("final_interior no greater than MAX_JUNCTIONS; qed");
}
Ok(())
}
/// Consume `self` and return its value prefixed with `prefix`.
///
/// Returns `Err` with the original value of `self` and `prefix` in case of overflow.
///
/// # Example
/// ```rust
/// # use staging_xcm::v4::{Junctions::*, Junction::*, Location, Parent};
/// # fn main() {
/// let m: Location = (Parent, Parent, PalletInstance(3)).into();
/// let r = m.prepended_with((Parent, Parachain(21), OnlyChild)).unwrap();
/// assert_eq!(r, Location::new(1, [PalletInstance(3)]));
/// # }
/// ```
pub fn prepended_with(mut self, prefix: impl Into<Self>) -> Result<Self, (Self, Self)> {
match self.prepend_with(prefix) {
Ok(()) => Ok(self),
Err(prefix) => Err((self, prefix)),
}
}
/// Remove any unneeded parents/junctions in `self` based on the given context it will be
/// interpreted in.
pub fn simplify(&mut self, context: &Junctions) {
if context.len() < self.parents as usize {
// Not enough context
return
}
while self.parents > 0 {
let maybe = context.at(context.len() - (self.parents as usize));
match (self.interior.first(), maybe) {
(Some(i), Some(j)) if i == j => {
self.interior.take_first();
self.parents -= 1;
},
_ => break,
}
}
}
/// Return the Location subsection identifying the chain that `self` points to.
pub fn chain_location(&self) -> Location {
let mut clone = self.clone();
// start popping junctions until we reach chain identifier
while let Some(j) = clone.last() {
if matches!(j, Junction::Parachain(_) | Junction::GlobalConsensus(_)) {
// return chain subsection
return clone
} else {
(clone, _) = clone.split_last_interior();
}
}
Location::new(clone.parents, Junctions::Here)
}
}
impl Reanchorable for Location {
type Error = Self;
/// Mutate `self` so that it represents the same location from the point of view of `target`.
/// The context of `self` is provided as `context`.
///
/// Does not modify `self` in case of overflow.
fn reanchor(&mut self, target: &Location, context: &InteriorLocation) -> Result<(), ()> {
// TODO: https://github.com/paritytech/polkadot/issues/4489 Optimize this.
// 1. Use our `context` to figure out how the `target` would address us.
let inverted_target = context.invert_target(target)?;
// 2. Prepend `inverted_target` to `self` to get self's location from the perspective of
// `target`.
self.prepend_with(inverted_target).map_err(|_| ())?;
// 3. Given that we know some of `target` context, ensure that any parents in `self` are
// strictly needed.
self.simplify(target.interior());
Ok(())
}
/// Consume `self` and return a new value representing the same location from the point of view
/// of `target`. The context of `self` is provided as `context`.
///
/// Returns the original `self` in case of overflow.
fn reanchored(mut self, target: &Location, context: &InteriorLocation) -> Result<Self, Self> {
match self.reanchor(target, context) {
Ok(()) => Ok(self),
Err(()) => Err(self),
}
}
}
impl TryFrom<OldLocation> for Option<Location> {
type Error = ();
fn try_from(value: OldLocation) -> result::Result<Self, Self::Error> {
Ok(Some(Location::try_from(value)?))
}
}
impl TryFrom<OldLocation> for Location {
type Error = ();
fn try_from(x: OldLocation) -> result::Result<Self, ()> {
Ok(Location { parents: x.parents, interior: x.interior.try_into()? })
}
}
/// A unit struct which can be converted into a `Location` of `parents` value 1.
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub struct Parent;
impl From<Parent> for Location {
fn from(_: Parent) -> Self {
Location { parents: 1, interior: Junctions::Here }
}
}
/// A tuple struct which can be converted into a `Location` of `parents` value 1 with the inner
/// interior.
#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub struct ParentThen(pub Junctions);
impl From<ParentThen> for Location {
fn from(ParentThen(interior): ParentThen) -> Self {
Location { parents: 1, interior }
}
}
/// A unit struct which can be converted into a `Location` of the inner `parents` value.
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub struct Ancestor(pub u8);
impl From<Ancestor> for Location {
fn from(Ancestor(parents): Ancestor) -> Self {
Location { parents, interior: Junctions::Here }
}
}
/// A unit struct which can be converted into a `Location` of the inner `parents` value and the
/// inner interior.
#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub struct AncestorThen<Interior>(pub u8, pub Interior);
impl<Interior: Into<Junctions>> From<AncestorThen<Interior>> for Location {
fn from(AncestorThen(parents, interior): AncestorThen<Interior>) -> Self {
Location { parents, interior: interior.into() }
}
}
impl From<[u8; 32]> for Location {
fn from(bytes: [u8; 32]) -> Self {
let junction: Junction = bytes.into();
junction.into()
}
}
xcm_procedural::impl_conversion_functions_for_location_v4!();
#[cfg(test)]
mod tests {
use crate::v4::prelude::*;
use codec::{Decode, Encode};
#[test]
fn conversion_works() {
let x: Location = Parent.into();
assert_eq!(x, Location { parents: 1, interior: Here });
// let x: Location = (Parent,).into();
// assert_eq!(x, Location { parents: 1, interior: Here });
// let x: Location = (Parent, Parent).into();
// assert_eq!(x, Location { parents: 2, interior: Here });
let x: Location = (Parent, Parent, OnlyChild).into();
assert_eq!(x, Location { parents: 2, interior: OnlyChild.into() });
let x: Location = OnlyChild.into();
assert_eq!(x, Location { parents: 0, interior: OnlyChild.into() });
let x: Location = (OnlyChild,).into();
assert_eq!(x, Location { parents: 0, interior: OnlyChild.into() });
}
#[test]
fn simplify_basic_works() {
let mut location: Location =
(Parent, Parent, Parachain(1000), PalletInstance(42), GeneralIndex(69)).into();
let context = [Parachain(1000), PalletInstance(42)].into();
let expected = GeneralIndex(69).into();
location.simplify(&context);
assert_eq!(location, expected);
let mut location: Location = (Parent, PalletInstance(42), GeneralIndex(69)).into();
let context = [PalletInstance(42)].into();
let expected = GeneralIndex(69).into();
location.simplify(&context);
assert_eq!(location, expected);
let mut location: Location = (Parent, PalletInstance(42), GeneralIndex(69)).into();
let context = [Parachain(1000), PalletInstance(42)].into();
let expected = GeneralIndex(69).into();
location.simplify(&context);
assert_eq!(location, expected);
let mut location: Location =
(Parent, Parent, Parachain(1000), PalletInstance(42), GeneralIndex(69)).into();
let context = [OnlyChild, Parachain(1000), PalletInstance(42)].into();
let expected = GeneralIndex(69).into();
location.simplify(&context);
assert_eq!(location, expected);
}
#[test]
fn simplify_incompatible_location_fails() {
let mut location: Location =
(Parent, Parent, Parachain(1000), PalletInstance(42), GeneralIndex(69)).into();
let context = [Parachain(1000), PalletInstance(42), GeneralIndex(42)].into();
let expected =
(Parent, Parent, Parachain(1000), PalletInstance(42), GeneralIndex(69)).into();
location.simplify(&context);
assert_eq!(location, expected);
let mut location: Location =
(Parent, Parent, Parachain(1000), PalletInstance(42), GeneralIndex(69)).into();
let context = [Parachain(1000)].into();
let expected =
(Parent, Parent, Parachain(1000), PalletInstance(42), GeneralIndex(69)).into();
location.simplify(&context);
assert_eq!(location, expected);
}
#[test]
fn reanchor_works() {
let mut id: Location = (Parent, Parachain(1000), GeneralIndex(42)).into();
let context = Parachain(2000).into();
let target = (Parent, Parachain(1000)).into();
let expected = GeneralIndex(42).into();
id.reanchor(&target, &context).unwrap();
assert_eq!(id, expected);
}
#[test]
fn encode_and_decode_works() {
let m = Location {
parents: 1,
interior: [Parachain(42), AccountIndex64 { network: None, index: 23 }].into(),
};
let encoded = m.encode();
assert_eq!(encoded, [1, 2, 0, 168, 2, 0, 92].to_vec());
let decoded = Location::decode(&mut &encoded[..]);
assert_eq!(decoded, Ok(m));
}
#[test]
fn match_and_split_works() {
let m = Location {
parents: 1,
interior: [Parachain(42), AccountIndex64 { network: None, index: 23 }].into(),
};
assert_eq!(m.match_and_split(&Location { parents: 1, interior: Here }), None);
assert_eq!(
m.match_and_split(&Location { parents: 1, interior: [Parachain(42)].into() }),
Some(&AccountIndex64 { network: None, index: 23 })
);
assert_eq!(m.match_and_split(&m), None);
}
#[test]
fn append_with_works() {
let acc = AccountIndex64 { network: None, index: 23 };
let mut m = Location { parents: 1, interior: [Parachain(42)].into() };
assert_eq!(m.append_with([PalletInstance(3), acc]), Ok(()));
assert_eq!(
m,
Location { parents: 1, interior: [Parachain(42), PalletInstance(3), acc].into() }
);
// cannot append to create overly long location
let acc = AccountIndex64 { network: None, index: 23 };
let m = Location {
parents: 254,
interior: [Parachain(42), OnlyChild, OnlyChild, OnlyChild, OnlyChild].into(),
};
let suffix: Location = (PalletInstance(3), acc, OnlyChild, OnlyChild).into();
assert_eq!(m.clone().append_with(suffix.clone()), Err(suffix));
}
#[test]
fn prepend_with_works() {
let mut m = Location {
parents: 1,
interior: [Parachain(42), AccountIndex64 { network: None, index: 23 }].into(),
};
assert_eq!(m.prepend_with(Location { parents: 1, interior: [OnlyChild].into() }), Ok(()));
assert_eq!(
m,
Location {
parents: 1,
interior: [Parachain(42), AccountIndex64 { network: None, index: 23 }].into()
}
);
// cannot prepend to create overly long location
let mut m = Location { parents: 254, interior: [Parachain(42)].into() };
let prefix = Location { parents: 2, interior: Here };
assert_eq!(m.prepend_with(prefix.clone()), Err(prefix));
let prefix = Location { parents: 1, interior: Here };
assert_eq!(m.prepend_with(prefix.clone()), Ok(()));
assert_eq!(m, Location { parents: 255, interior: [Parachain(42)].into() });
}
#[test]
fn double_ended_ref_iteration_works() {
let m: Junctions = [Parachain(1000), Parachain(3), PalletInstance(5)].into();
let mut iter = m.iter();
let first = iter.next().unwrap();
assert_eq!(first, &Parachain(1000));
let third = iter.next_back().unwrap();
assert_eq!(third, &PalletInstance(5));
let second = iter.next_back().unwrap();
assert_eq!(iter.next(), None);
assert_eq!(iter.next_back(), None);
assert_eq!(second, &Parachain(3));
let res = Here
.pushed_with(*first)
.unwrap()
.pushed_with(*second)
.unwrap()
.pushed_with(*third)
.unwrap();
assert_eq!(m, res);
// make sure there's no funny business with the 0 indexing
let m = Here;
let mut iter = m.iter();
assert_eq!(iter.next(), None);
assert_eq!(iter.next_back(), None);
}
#[test]
fn conversion_from_other_types_works() {
use crate::v3;
fn takes_location<Arg: Into<Location>>(_arg: Arg) {}
takes_location(Parent);
takes_location(Here);
takes_location([Parachain(42)]);
takes_location((Ancestor(255), PalletInstance(8)));
takes_location((Ancestor(5), Parachain(1), PalletInstance(3)));
takes_location((Ancestor(2), Here));
takes_location(AncestorThen(
3,
[Parachain(43), AccountIndex64 { network: None, index: 155 }],
));
takes_location((Parent, AccountId32 { network: None, id: [0; 32] }));
takes_location((Parent, Here));
takes_location(ParentThen([Parachain(75)].into()));
takes_location([Parachain(100), PalletInstance(3)]);
assert_eq!(v3::Location::from(v3::Junctions::Here).try_into(), Ok(Location::here()));
assert_eq!(v3::Location::from(v3::Parent).try_into(), Ok(Location::parent()));
assert_eq!(
v3::Location::from((v3::Parent, v3::Parent, v3::Junction::GeneralIndex(42u128),))
.try_into(),
Ok(Location { parents: 2, interior: [GeneralIndex(42u128)].into() }),
);
}
}