Companion for Substrate#10655 (#4765)

* Companion for Substrate#10655

https://github.com/paritytech/substrate/pull/10655

This removes the last usages of `Default` in conjunction with `AccountId`

* More fixes

* More of them!

* FMT

* Update Substrate

polkadot/bridges/modules/dispatch/src/lib.rs

@@ -64,8 +64,7 @@ pub mod pallet {
 			+ MaybeSerializeDeserialize
 			+ Debug
 			+ MaybeDisplay
-			+ Ord
+			+ Ord;
-			+ Default;
 		/// Type of account public key on target chain.
 		type TargetChainAccountPublic: Parameter + IdentifyAccount<AccountId = Self::AccountId>;
 		/// Type of signature that may prove that the message has been signed by

polkadot/bridges/primitives/polkadot-core/src/lib.rs

@@ -409,11 +409,13 @@ pub fn account_info_storage_key(id: &AccountId) -> Vec<u8> {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use sp_runtime::codec::Encode;
+	use parity_scale_codec::Decode;
+	use sp_runtime::{codec::Encode, traits::TrailingZeroInput};
 
 	#[test]
 	fn maximal_encoded_account_id_size_is_correct() {
-		let actual_size = AccountId::default().encode().len();
+		let actual_size =
+			AccountId::decode(&mut TrailingZeroInput::new(&[])).unwrap().encode().len();
 		assert!(
 			actual_size <= MAXIMAL_ENCODED_ACCOUNT_ID_SIZE as usize,
 			"Actual size of encoded account id for Polkadot-like chains ({}) is larger than expected {}",

polkadot/bridges/primitives/runtime/src/chain.rs

@@ -82,13 +82,8 @@ pub trait Chain: Send + Sync + 'static {
 		+ MaybeSerializeDeserialize;
 
 	/// The user account identifier type for the runtime.
-	type AccountId: Parameter
+	type AccountId: Parameter + Member + MaybeSerializeDeserialize + Debug + MaybeDisplay + Ord;
-		+ Member
+
-		+ MaybeSerializeDeserialize
-		+ Debug
-		+ MaybeDisplay
-		+ Ord
-		+ Default;
 	/// Balance of an account in native tokens.
 	///
 	/// The chain may support multiple tokens, but this particular type is for token that is used

polkadot/parachain/src/primitives.rs

@@ -305,11 +305,11 @@ impl<'a> parity_scale_codec::Input for TrailingZeroInput<'a> {
 
 /// Format is b"para" ++ encode(parachain ID) ++ 00.... where 00... is indefinite trailing
 /// zeroes to fill [`AccountId`].
-impl<T: Encode + Decode + Default> AccountIdConversion<T> for Id {
+impl<T: Encode + Decode> AccountIdConversion<T> for Id {
 	fn into_account(&self) -> T {
 		(b"para", self)
 			.using_encoded(|b| T::decode(&mut TrailingZeroInput(b)))
-			.unwrap_or_default()
+			.expect("infinite length input; no invalid inputs for type; qed")
 	}
 
 	fn try_from_account(x: &T) -> Option<Self> {

polkadot/runtime/common/src/impls.rs

@@ -74,6 +74,7 @@ mod tests {
 
 	type UncheckedExtrinsic = frame_system::mocking::MockUncheckedExtrinsic<Test>;
 	type Block = frame_system::mocking::MockBlock<Test>;
+	const TEST_ACCOUNT: AccountId = AccountId::new([1; 32]);
 
 	frame_support::construct_runtime!(
 		pub enum Test where
@@ -171,7 +172,7 @@ mod tests {
 		where
 			I: 'a,
 		{
-			Some(Default::default())
+			Some(TEST_ACCOUNT)
 		}
 	}
 	impl pallet_authorship::Config for Test {
@@ -197,12 +198,12 @@ mod tests {
 			let tip = Balances::issue(20);
 
 			assert_eq!(Balances::free_balance(Treasury::account_id()), 0);
-			assert_eq!(Balances::free_balance(AccountId::default()), 0);
+			assert_eq!(Balances::free_balance(TEST_ACCOUNT), 0);
 
 			DealWithFees::on_unbalanceds(vec![fee, tip].into_iter());
 
 			// Author gets 100% of tip and 20% of fee = 22
-			assert_eq!(Balances::free_balance(AccountId::default()), 22);
+			assert_eq!(Balances::free_balance(TEST_ACCOUNT), 22);
 			// Treasury gets 80% of fee
 			assert_eq!(Balances::free_balance(Treasury::account_id()), 8);
 		});