Deprecate Currency; introduce holds and freezing into fungible traits (#12951)

* First reworking of fungibles API

* New API and docs

* More fungible::* API improvements

* New ref-counting logic for old API

* Missing files

* Fixes

* Use the new transfer logic

* Use fungibles for the dispatchables

* Use shelve/restore names

* Locking works with total balance.

* repotting and removal

* Separate Holds from Reserves

* Introduce freezes

* Missing files

* Tests for freezing

* Fix hold+freeze combo

* More tests

* Fee-free dispatchable for upgrading accounts

* Benchmarks and a few fixes

* Another test

* Docs and refactor to avoid blanket impls

* Repot

* Fit out ItemOf fully

* Add events to Balanced traits

* Introduced events into Hold traits

* Fix Assets pallet tests

* Assets benchmarks pass

* Missing files and fixes

* Fixes

* Fixes

* Benchmarks fixes

* Fix balance benchmarks

* Formatting

* Expose fungible sub modules

* Move NIS to fungible API

* Fix broken impl and add test

* Fix tests

* API for `transfer_and_hold`

* Use composite APIs

* Formatting

* Upgraded event

* Fixes

* Fixes

* Fixes

* Fixes

* Repot tests and some fixed

* Fix some bits

* Fix dust tests

* Rename `set_balance`

- `Balances::set_balance` becomes `Balances::force_set_balance`
- `Unbalanced::set_balance` becomes `Unbalances::write_balance`

* becomes

* Move dust handling to fungibles API

* Formatting

* Fixes and more refactoring

* Fixes

* Fixes

* Fixes

* Fixes

* Fixes

* Fixes

* Fixes

* Fixes

* Fixes

* Use reducible_balance for better correctness on fees

* Reducing hold to zero should remove entry.

* Add test

* Docs

* Update frame/support/src/traits/tokens/fungibles/hold.rs

Co-authored-by: Muharem Ismailov <ismailov.m.h@gmail.com>

* Update frame/support/src/traits/tokens/fungibles/regular.rs

Co-authored-by: Muharem Ismailov <ismailov.m.h@gmail.com>

* Update frame/support/src/traits/tokens/fungible/hold.rs

Co-authored-by: Muharem Ismailov <ismailov.m.h@gmail.com>

* Update frame/support/src/traits/tokens/fungible/regular.rs

Co-authored-by: Muharem Ismailov <ismailov.m.h@gmail.com>

* Docs

* Docs

* Docs

* Fix NIS benchmarks

* Doc comment

* Remove post_mutation

* Fix some tests

* Fix some grumbles

* Enumify bool args to fungible(s) functions

* Fix up assets and balances

* Formatting

* Fix contracts

* Fix tests & benchmarks build

* Typify minted boolean arg

* Typify on_hold boolean arg; renames

* Fix numerous tests

* Fix dependency issue

* Privatize dangerous API mutate_account

* Fix contracts (@alext - please check this commit)

* Remove println

* Fix tests for contracts

* Fix broken rename

* Fix broken rename

* Fix broken rename

* Docs

* Update frame/support/src/traits/tokens/fungible/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* remove from_ref_time

* Update frame/executive/src/lib.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/executive/src/lib.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Reenable test

* Update frame/support/src/traits/tokens/fungibles/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungible/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungible/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungible/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/currency.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/lottery/src/tests.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungible/mod.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungible/regular.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungibles/freeze.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungible/regular.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungibles/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungibles/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Update frame/support/src/traits/tokens/fungibles/hold.rs

Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>

* Rename UnwantedRemoval to UnwantedAccountRemoval

* Docs

* Formatting

* Update frame/balances/src/lib.rs

Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* Update primitives/runtime/src/lib.rs

Co-authored-by: Keith Yeung <kungfukeith11@gmail.com>

* handle_raw_dust oes nothing

* Formatting

* Fixes

* Grumble

* Fixes

* Add test

* Add test

* Tests for reducible_balance

* Fixes

* Fix Salary

* Fixes

* Disable broken test

* Disable nicely

* Fixes

* Fixes

* Fixes

* Rename some events

* Fix nomination pools breakage

* Add compatibility stub for transfer tx

* Reinstate a safely compatible version of Balances set_balance

* Fixes

* Grumble

* Update frame/nis/src/lib.rs

Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

* ".git/.scripts/commands/bench/bench.sh" pallet dev pallet_balances

* disable flakey tests

* Update frame/balances/src/lib.rs

Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

* Grumbles

* Grumble

---------

Co-authored-by: Muharem Ismailov <ismailov.m.h@gmail.com>
Co-authored-by: Alexander Theißen <alex.theissen@me.com>
Co-authored-by: Anthony Alaribe <anthonyalaribe@gmail.com>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Keith Yeung <kungfukeith11@gmail.com>
Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>
Co-authored-by: command-bot <>

substrate/primitives/runtime/src/lib.rs

@@ -606,9 +606,10 @@ impl From<crate::traits::BadOrigin> for DispatchError {
 #[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
 pub enum TokenError {
 	/// Funds are unavailable.
-	NoFunds,
-	/// Account that must exist would die.
-	WouldDie,
+	FundsUnavailable,
+	/// Some part of the balance gives the only provider reference to the account and thus cannot
+	/// be (re)moved.
+	OnlyProvider,
 	/// Account cannot exist with the funds that would be given.
 	BelowMinimum,
 	/// Account cannot be created.
@@ -619,18 +620,25 @@ pub enum TokenError {
 	Frozen,
 	/// Operation is not supported by the asset.
 	Unsupported,
+	/// Account cannot be created for a held balance.
+	CannotCreateHold,
+	/// Withdrawal would cause unwanted loss of account.
+	NotExpendable,
 }
 
 impl From<TokenError> for &'static str {
 	fn from(e: TokenError) -> &'static str {
 		match e {
-			TokenError::NoFunds => "Funds are unavailable",
-			TokenError::WouldDie => "Account that must exist would die",
+			TokenError::FundsUnavailable => "Funds are unavailable",
+			TokenError::OnlyProvider => "Account that must exist would die",
 			TokenError::BelowMinimum => "Account cannot exist with the funds that would be given",
 			TokenError::CannotCreate => "Account cannot be created",
 			TokenError::UnknownAsset => "The asset in question is unknown",
 			TokenError::Frozen => "Funds exist but are frozen",
 			TokenError::Unsupported => "Operation is not supported by the asset",
+			TokenError::CannotCreateHold =>
+				"Account cannot be created for recording amount on hold",
+			TokenError::NotExpendable => "Account that is desired to remain would die",
 		}
 	}
 }
@@ -994,8 +1002,8 @@ mod tests {
 			Module(ModuleError { index: 2, error: [1, 0, 0, 0], message: None }),
 			ConsumerRemaining,
 			NoProviders,
-			Token(TokenError::NoFunds),
-			Token(TokenError::WouldDie),
+			Token(TokenError::FundsUnavailable),
+			Token(TokenError::OnlyProvider),
 			Token(TokenError::BelowMinimum),
 			Token(TokenError::CannotCreate),
 			Token(TokenError::UnknownAsset),