Implement a proper generic resolution in decl_storage! (#2913)

* Add failing test case

* move storage maps to blake2_128 (#2268)

* remove default hash, introduce twox_128 and blake2

* use blake2_128 & create ext_blake2_128

* refactor code

* add benchmark

* factorize generator

* fix

* parameterizable hasher

* some fix

* fix

* fix

* fix

* metadata

* fix

* remove debug print

* map -> blake2_256

* fix test

* fix test

* Apply suggestions from code review

Co-Authored-By: thiolliere <gui.thiolliere@gmail.com>

* impl twox 128 concat (#2353)

* impl twox_128_concat

* comment addressed

* fix

* impl twox_128->64_concat

* fix test

* Fix compilation and cleanup some docs

* Lol

* Remove traits from storage types that are not generic

* Get instance test almost working as wanted

* Make `srml-support-test` compile again :)

* Fixes test of srml-support

* Fix compilation

* Break some lines

* Remove incorrect macro match arm

* Integrates review feedback

* Update documentation

* Fix compilation

substrate/srml/staking/src/lib.rs

@@ -866,7 +866,7 @@ decl_module! {
 
 		/// The ideal number of validators.
 		fn set_validator_count(#[compact] new: u32) {
-			<ValidatorCount<T>>::put(new);
+			ValidatorCount::put(new);
 		}
 
 		// ----- Root calls.
@@ -885,7 +885,7 @@ decl_module! {
 
 		/// Set the offline slash grace period.
 		fn set_offline_slash_grace(#[compact] new: u32) {
-			<OfflineSlashGrace<T>>::put(new);
+			OfflineSlashGrace::put(new);
 		}
 
 		/// Set the validators who cannot be slashed (if any).
@@ -1004,7 +1004,7 @@ impl<T: Trait> Module<T> {
 		let reward = Self::current_session_reward();
 		<CurrentEraReward<T>>::mutate(|r| *r += reward);
 
-		if <ForceNewEra<T>>::take() || session_index % T::SessionsPerEra::get() == 0 {
+		if ForceNewEra::take() || session_index % T::SessionsPerEra::get() == 0 {
 			Self::new_era()
 		} else {
 			None
@@ -1032,7 +1032,7 @@ impl<T: Trait> Module<T> {
 		}
 
 		// Increment current era.
-		<CurrentEra<T>>::mutate(|s| *s += 1);
+		CurrentEra::mutate(|s| *s += 1);
 
 		// Reassign all Stakers.
 		let (slot_stake, maybe_new_validators) = Self::select_validators();
@@ -1161,7 +1161,7 @@ impl<T: Trait> Module<T> {
 	}
 
 	fn apply_force_new_era() {
-		<ForceNewEra<T>>::put(true);
+		ForceNewEra::put(true);
 	}
 
 	/// Call when a validator is determined to be offline. `count` is the

substrate/srml/staking/src/mock.rs

@@ -17,7 +17,7 @@
 //! Test utilities
 
 use std::{collections::HashSet, cell::RefCell};
-use primitives::{BuildStorage, Perbill};
+use primitives::Perbill;
 use primitives::traits::{IdentityLookup, Convert, OpaqueKeys, OnInitialize};
 use primitives::testing::{Header, UintAuthorityId};
 use substrate_primitives::{H256, Blake2Hasher};
@@ -179,7 +179,7 @@ impl ExtBuilder {
 		self
 	}
 	pub fn build(self) -> runtime_io::TestExternalities<Blake2Hasher> {
-		let (mut t, mut c) = system::GenesisConfig::<Test>::default().build_storage().unwrap();
+		let (mut t, mut c) = system::GenesisConfig::default().build_storage::<Test>().unwrap();
 		let balance_factor = if self.existential_deposit > 0 {
 			256
 		} else {

substrate/srml/staking/src/tests.rs

@@ -257,7 +257,7 @@ fn max_unstake_threshold_works() {
 			validator_payment: 0,
 		});
 
-		<OfflineSlash<Test>>::put(Perbill::from_fraction(0.0001));
+		OfflineSlash::put(Perbill::from_fraction(0.0001));
 
 		// Report each user 1 more than the max_unstake_threshold
 		Staking::on_offline_validator(10, MAX_UNSTAKE_THRESHOLD as usize + 1);
@@ -696,7 +696,7 @@ fn nominators_also_get_slashed() {
 		assert_eq!(Staking::offline_slash_grace(), 0);
 		// Account 10 has not been reported offline
 		assert_eq!(Staking::slash_count(&10), 0);
-		<OfflineSlash<Test>>::put(Perbill::from_percent(12));
+		OfflineSlash::put(Perbill::from_percent(12));
 
 		// Set payee to controller
 		assert_ok!(Staking::set_payee(Origin::signed(10), RewardDestination::Controller));