Assign unique storage names to pallets. (#5010)

* Assign unique storage names to pallets.

* Bump spec

* Upgrade logic for finality tracker (untested)

* Logic for migrating Identity (untested)

* Logic for migrating transaction-payment

* Fix tests

* Fix `decl_storage` build

* Contract -> Contracts

* Update Cargo.lock

* bump spec

* update migration

* Fix merge error

* Migration for contracts

* Remove serde

* Remove some illegal spaces and Options

* Fix types in identity.

* Minor variable rename

Co-authored-by: Gavin Wood <gavin@parity.io>

substrate/frame/transaction-payment/src/lib.rs

@@ -48,6 +48,8 @@ use sp_runtime::{
 };
 use pallet_transaction_payment_rpc_runtime_api::RuntimeDispatchInfo;
 
+mod migration;
+
 type Multiplier = Fixed64;
 type BalanceOf<T> =
 	<<T as Trait>::Currency as Currency<<T as frame_system::Trait>::AccountId>>::Balance;
@@ -77,7 +79,7 @@ pub trait Trait: frame_system::Trait {
 }
 
 decl_storage! {
-	trait Store for Module<T: Trait> as Balances {
+	trait Store for Module<T: Trait> as TransactionPayment {
 		pub NextFeeMultiplier get(fn next_fee_multiplier): Multiplier = Multiplier::from_parts(0);
 	}
 }
@@ -95,6 +97,10 @@ decl_module! {
 				*fm = T::FeeMultiplierUpdate::convert(*fm)
 			});
 		}
+
+		fn on_runtime_upgrade() {
+			migration::on_runtime_upgrade()
+		}
 	}
 }
 

substrate/frame/transaction-payment/src/migration.rs

@@ -0,0 +1,38 @@
+// Copyright 2020 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate 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.
+
+// Substrate 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 Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Migration code to update storage.
+
+use super::*;
+use frame_support::storage::migration::{put_storage_value, take_storage_value};
+
+pub fn on_runtime_upgrade() {
+	change_name_balances_to_transaction_payment()
+}
+
+// Change the storage name used by this pallet from `Balances` to `TransactionPayment`.
+//
+// Since the format of the storage items themselves have not changed, we do not
+// need to keep track of a storage version. If the runtime does not need to be
+// upgraded, nothing here will happen anyway.
+
+fn change_name_balances_to_transaction_payment() {
+	sp_runtime::print("Migrating Transaction Payment.");
+
+	if let Some(next_fee_multiplier) = take_storage_value::<Multiplier>(b"Balances", b"NextFeeMultiplier", &[]) {
+		put_storage_value(b"TransactionPayment", b"NextFeeMultiplier", &[], next_fee_multiplier);
+	}
+}