A random beacon (#96)

* Completely rework dispatch mechanism into something modular.

Not yet complete but 75% there.

* Council vote tests.

* Fix tests.

* whitespace.

* Fix demo runtime tests.

* Fix up tests.

* Remove dead code.

* Initial util code for random beacon

* Timestamp uses new storage API.

* Move over system module to new API.

* Much nicer storage API, moved over staking module.

* More refactoring.

* Democracy uses new storage API.

* Council uses new RPC.

* Fix more tests.

* Use match for Id

* Generic mix.

* Integrate random beacon

* Update binaries.

* Fixes relating to with_ext removal.

* Remove dead code.

* Rework mixer into an iterator adaptor.

* Link to paper.

* Algorithm cleanups

* Merge and fix test.

* Docs.

* Fix typo.

* rename

* Fix tests.

substrate/demo/executor/src/lib.rs

@@ -46,7 +46,8 @@ mod tests {
 	use demo_primitives::{Hash, Header, BlockNumber, Digest};
 	use demo_runtime::transaction::{Transaction, UncheckedTransaction};
 	use demo_runtime::block::Block;
-	use demo_runtime::runtime::staking::{self, FreeBalanceOf, balance};
+	use demo_runtime::runtime::staking::{FreeBalanceOf, balance};
+	use demo_runtime::runtime::{staking, system};
 	use demo_runtime::dispatch;
 	use ed25519::{Public, Pair};
 
@@ -76,10 +77,13 @@ mod tests {
 	fn panic_execution_with_foreign_code_gives_error() {
 		let mut t: TestExternalities = map![
 			twox_128(&FreeBalanceOf::key_for(*Alice)).to_vec() => vec![68u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8],
+			twox_128(&system::BlockHashAt::key_for(0)).to_vec() => vec![0u8; 32]
 		];
 
-		let r = Executor::new().call(&mut t, BLOATY_CODE, "execute_transaction", &vec![].and(&Header::from_block_number(1u64)).and(&tx()));
+		let r = Executor::new().call(&mut t, BLOATY_CODE, "initialise_block", &vec![].and(&Header::from_block_number(1u64)));
+		assert!(r.is_ok());
+		let r = Executor::new().call(&mut t, BLOATY_CODE, "execute_transaction", &vec![].and(&tx()));
 		assert!(r.is_err());
 	}
 
@@ -87,10 +91,13 @@ mod tests {
 	fn panic_execution_with_native_equivalent_code_gives_error() {
 		let mut t: TestExternalities = map![
 			twox_128(&FreeBalanceOf::key_for(*Alice)).to_vec() => vec![68u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8],
+			twox_128(&system::BlockHashAt::key_for(0)).to_vec() => vec![0u8; 32]
 		];
 
-		let r = Executor::new().call(&mut t, COMPACT_CODE, "execute_transaction", &vec![].and(&Header::from_block_number(1u64)).and(&tx()));
+		let r = Executor::new().call(&mut t, COMPACT_CODE, "initialise_block", &vec![].and(&Header::from_block_number(1u64)));
+		assert!(r.is_ok());
+		let r = Executor::new().call(&mut t, COMPACT_CODE, "execute_transaction", &vec![].and(&tx()));
 		assert!(r.is_err());
 	}
 
@@ -98,10 +105,13 @@ mod tests {
 	fn successful_execution_with_native_equivalent_code_gives_ok() {
 		let mut t: TestExternalities = map![
 			twox_128(&FreeBalanceOf::key_for(*Alice)).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8],
+			twox_128(&system::BlockHashAt::key_for(0)).to_vec() => vec![0u8; 32]
 		];
 
-		let r = Executor::new().call(&mut t, COMPACT_CODE, "execute_transaction", &vec![].and(&Header::from_block_number(1u64)).and(&tx()));
+		let r = Executor::new().call(&mut t, COMPACT_CODE, "initialise_block", &vec![].and(&Header::from_block_number(1u64)));
+		assert!(r.is_ok());
+		let r = Executor::new().call(&mut t, COMPACT_CODE, "execute_transaction", &vec![].and(&tx()));
 		assert!(r.is_ok());
 
 		runtime_io::with_externalities(&mut t, || {
@@ -114,10 +124,13 @@ mod tests {
 	fn successful_execution_with_foreign_code_gives_ok() {
 		let mut t: TestExternalities = map![
 			twox_128(&FreeBalanceOf::key_for(*Alice)).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8],
+			twox_128(&system::BlockHashAt::key_for(0)).to_vec() => vec![0u8; 32]
 		];
 
-		let r = Executor::new().call(&mut t, BLOATY_CODE, "execute_transaction", &vec![].and(&Header::from_block_number(1u64)).and(&tx()));
+		let r = Executor::new().call(&mut t, BLOATY_CODE, "initialise_block", &vec![].and(&Header::from_block_number(1u64)));
+		assert!(r.is_ok());
+		let r = Executor::new().call(&mut t, BLOATY_CODE, "execute_transaction", &vec![].and(&tx()));
 		assert!(r.is_ok());
 
 		runtime_io::with_externalities(&mut t, || {
@@ -229,11 +242,14 @@ mod tests {
 	fn panic_execution_gives_error() {
 		let mut t: TestExternalities = map![
 			twox_128(&FreeBalanceOf::key_for(*Alice)).to_vec() => vec![68u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8],
+			twox_128(&system::BlockHashAt::key_for(0)).to_vec() => vec![0u8; 32]
 		];
 
 		let foreign_code = include_bytes!("../../runtime/wasm/target/wasm32-unknown-unknown/release/demo_runtime.wasm");
-		let r = WasmExecutor.call(&mut t, &foreign_code[..], "execute_transaction", &vec![].and(&Header::from_block_number(1u64)).and(&tx()));
+		let r = WasmExecutor.call(&mut t, &foreign_code[..], "initialise_block", &vec![].and(&Header::from_block_number(1u64)));
+		assert!(r.is_ok());
+		let r = WasmExecutor.call(&mut t, &foreign_code[..], "execute_transaction", &vec![].and(&tx()));
 		assert!(r.is_err());
 	}
 
@@ -241,11 +257,14 @@ mod tests {
 	fn successful_execution_gives_ok() {
 		let mut t: TestExternalities = map![
 			twox_128(&FreeBalanceOf::key_for(*Alice)).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![0u8; 8],
+			twox_128(&system::BlockHashAt::key_for(0)).to_vec() => vec![0u8; 32]
 		];
 
 		let foreign_code = include_bytes!("../../runtime/wasm/target/wasm32-unknown-unknown/release/demo_runtime.compact.wasm");
-		let r = WasmExecutor.call(&mut t, &foreign_code[..], "execute_transaction", &vec![].and(&Header::from_block_number(1u64)).and(&tx()));
+		let r = WasmExecutor.call(&mut t, &foreign_code[..], "initialise_block", &vec![].and(&Header::from_block_number(1u64)));
+		assert!(r.is_ok());
+		let r = WasmExecutor.call(&mut t, &foreign_code[..], "execute_transaction", &vec![].and(&tx()));
 		assert!(r.is_ok());
 
 		runtime_io::with_externalities(&mut t, || {

substrate/demo/runtime/src/api.rs

@@ -18,8 +18,9 @@ use runtime::{system, consensus, session};
 
 impl_stubs!(
 	execute_block => |block| system::internal::execute_block(block),
-	execute_transaction => |(header, utx)| system::internal::execute_transaction(utx, header),
+	initialise_block => |header| system::internal::initialise_block(&header),
-	finalise_block => |header| system::internal::finalise_block(header),
+	execute_transaction => |utx| system::internal::execute_transaction(utx),
+	finalise_block => |()| system::internal::finalise_block(),
 	validator_count => |()| session::validator_count(),
 	validators => |()| session::validators(),
 	authorities => |()| consensus::authorities()

substrate/demo/runtime/src/environment.rs

@@ -1,82 +0,0 @@
-// Copyright 2017 Parity Technologies (UK) Ltd.
-// This file is part of Substrate Demo.
-
-// Substrate Demo 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 Demo 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 Demo.  If not, see <http://www.gnu.org/licenses/>.
-
-//! Environment API: Allows certain information to be accessed throughout the runtime.
-
-use rstd::boxed::Box;
-use rstd::mem;
-use rstd::cell::RefCell;
-use rstd::rc::Rc;
-
-use demo_primitives::{BlockNumber, Digest, Hash};
-
-#[derive(Default)]
-/// The information that can be accessed globally.
-pub struct Environment {
-	/// The current block number.
-	pub block_number: BlockNumber,
-	/// The current block's parent hash.
-	pub parent_hash: Hash,
-	/// The current block digest.
-	pub digest: Digest,
-}
-
-/// Do something with the environment and return its value. Keep the function short.
-pub fn with_env<T, F: FnOnce(&mut Environment) -> T>(f: F) -> T {
-	let e = env();
-	let mut eb = e.borrow_mut();
-	f(&mut *eb)
-}
-
-#[cfg(target_arch = "wasm32")]
-fn env() -> Rc<RefCell<Environment>> {
-	// Initialize it to a null value
-	static mut SINGLETON: *const Rc<RefCell<Environment>> = 0 as *const Rc<RefCell<Environment>>;
-
-	unsafe {
-		if SINGLETON == 0 as *const Rc<RefCell<Environment>> {
-			// Make it
-			let singleton: Rc<RefCell<Environment>> = Rc::new(RefCell::new(Default::default()));
-
-			// Put it in the heap so it can outlive this call
-			SINGLETON = mem::transmute(Box::new(singleton));
-		}
-
-		// Now we give out a copy of the data that is safe to use concurrently.
-		(*SINGLETON).clone()
-	}
-}
-
-#[cfg(not(target_arch = "wasm32"))]
-fn env() -> Rc<RefCell<Environment>> {
-	// Initialize it to a null value
-	thread_local!{
-		static SINGLETON: RefCell<*const Rc<RefCell<Environment>>> = RefCell::new(0 as *const Rc<RefCell<Environment>>);
-	}
-
-	SINGLETON.with(|s| unsafe {
-		if *s.borrow() == 0 as *const Rc<RefCell<Environment>> {
-			// Make it
-			let singleton: Rc<RefCell<Environment>> = Rc::new(RefCell::new(Default::default()));
-
-			// Put it in the heap so it can outlive this call
-			*s.borrow_mut() = mem::transmute(Box::new(singleton));
-		}
-
-		// Now we give out a copy of the data that is safe to use concurrently.
-		(**s.borrow()).clone()
-	})
-}

substrate/demo/runtime/src/lib.rs

@@ -38,9 +38,9 @@ extern crate integer_sqrt;
 
 #[macro_use] pub mod dispatch;
 
+pub mod safe_mix;
 pub mod block;
 pub mod transaction;
-pub mod environment;
 pub mod runtime;
 pub mod api;
 

substrate/demo/runtime/src/runtime/council.rs

@@ -508,7 +508,6 @@ mod tests {
 	use runtime_io::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
 	use keyring::Keyring::*;
-	use environment::with_env;
 	use demo_primitives::AccountId;
 	use runtime::{staking, session, democracy};
 	use super::public::Dispatch;
@@ -522,7 +521,7 @@ mod tests {
 	fn basic_environment_works() {
 		let mut t = new_test_ext();
 		with_externalities(&mut t, || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(next_vote_from(1), 4);
 			assert_eq!(next_vote_from(4), 4);
 			assert_eq!(next_vote_from(5), 8);
@@ -554,7 +553,7 @@ mod tests {
 	#[test]
 	fn simple_candidate_submission_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), Vec::<AccountId>::new());
 			assert_eq!(candidate_reg_info(*Alice), None);
 			assert_eq!(candidate_reg_info(*Bob), None);
@@ -590,7 +589,7 @@ mod tests {
 		let mut t = new_test_ext_with_candidate_holes();
 
 		with_externalities(&mut t, || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), vec![AccountId::default(), AccountId::default(), Alice.to_raw_public()]);
 
 			PublicPass::test(&Bob).submit_candidacy(1);
@@ -606,7 +605,7 @@ mod tests {
 		let mut t = new_test_ext_with_candidate_holes();
 
 		with_externalities(&mut t, || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), vec![AccountId::default(), AccountId::default(), Alice.into()]);
 
 			PublicPass::test(&Bob).submit_candidacy(0);
@@ -623,7 +622,7 @@ mod tests {
 		let mut t = new_test_ext_with_candidate_holes();
 
 		with_externalities(&mut t, || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			PublicPass::test(&Dave).submit_candidacy(3);
 		});
 	}
@@ -632,7 +631,7 @@ mod tests {
 	#[should_panic(expected = "invalid candidate slot")]
 	fn bad_candidate_slot_submission_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), Vec::<AccountId>::new());
 			PublicPass::test(&Alice).submit_candidacy(1);
 		});
@@ -642,7 +641,7 @@ mod tests {
 	#[should_panic(expected = "invalid candidate slot")]
 	fn non_free_candidate_slot_submission_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), Vec::<AccountId>::new());
 			PublicPass::test(&Alice).submit_candidacy(0);
 			PublicPass::test(&Bob).submit_candidacy(0);
@@ -653,7 +652,7 @@ mod tests {
 	#[should_panic(expected = "duplicate candidate submission")]
 	fn dupe_candidate_submission_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), Vec::<AccountId>::new());
 			PublicPass::test(&Alice).submit_candidacy(0);
 			PublicPass::test(&Alice).submit_candidacy(1);
@@ -664,7 +663,7 @@ mod tests {
 	#[should_panic(expected = "candidate has not enough funds")]
 	fn poor_candidate_submission_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(candidates(), Vec::<AccountId>::new());
 			PublicPass::test(&One).submit_candidacy(0);
 		});
@@ -673,7 +672,7 @@ mod tests {
 	#[test]
 	fn voting_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 
 			PublicPass::test(&Eve).submit_candidacy(0);
 
@@ -702,7 +701,7 @@ mod tests {
 	#[test]
 	fn resubmitting_voting_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Dave).set_approvals(vec![true], 0);
@@ -720,7 +719,7 @@ mod tests {
 	#[test]
 	fn retracting_voter_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Bob).submit_candidacy(1);
@@ -767,7 +766,7 @@ mod tests {
 	#[should_panic(expected = "retraction index mismatch")]
 	fn invalid_retraction_index_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			PublicPass::test(&Charlie).submit_candidacy(0);
 			PublicPass::test(&Alice).set_approvals(vec![true], 0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
@@ -779,7 +778,7 @@ mod tests {
 	#[should_panic(expected = "retraction index invalid")]
 	fn overflow_retraction_index_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			PublicPass::test(&Charlie).submit_candidacy(0);
 			PublicPass::test(&Alice).set_approvals(vec![true], 0);
 			PublicPass::test(&Alice).retract_voter(1);
@@ -790,7 +789,7 @@ mod tests {
 	#[should_panic(expected = "cannot retract non-voter")]
 	fn non_voter_retraction_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			PublicPass::test(&Charlie).submit_candidacy(0);
 			PublicPass::test(&Alice).set_approvals(vec![true], 0);
 			PublicPass::test(&Bob).retract_voter(0);
@@ -800,7 +799,7 @@ mod tests {
 	#[test]
 	fn simple_tally_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			assert!(!presentation_active());
 
 			PublicPass::test(&Bob).submit_candidacy(0);
@@ -809,7 +808,7 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			assert!(presentation_active());
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 0);
@@ -833,14 +832,14 @@ mod tests {
 		with_externalities(&mut new_test_ext(), || {
 			assert!(staking::can_slash(&Dave, 10));
 
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Eve).submit_candidacy(1);
 			PublicPass::test(&Bob).set_approvals(vec![true, false], 0);
 			PublicPass::test(&Eve).set_approvals(vec![false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 0);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 0);
@@ -854,21 +853,21 @@ mod tests {
 	#[test]
 	fn retracting_inactive_voter_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Eve).set_approvals(vec![true], 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 1);
 			internal::end_block();
 
@@ -889,21 +888,21 @@ mod tests {
 	#[should_panic(expected = "candidate must not form a duplicated member if elected")]
 	fn presenting_for_double_election_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 1);
 		});
 	}
@@ -911,25 +910,25 @@ mod tests {
 	#[test]
 	fn retracting_inactive_voter_with_other_candidates_in_slots_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Eve).set_approvals(vec![true], 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 11);
+			system::testing::set_block_number(11);
 			PublicPass::test(&Alice).submit_candidacy(0);
 
 			PublicPass::test(&Eve).reap_inactive_voter(
@@ -949,21 +948,21 @@ mod tests {
 	#[should_panic(expected = "bad reporter index")]
 	fn retracting_inactive_voter_with_bad_reporter_index_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 8, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Eve).set_approvals(vec![true], 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 38, 1);
 			internal::end_block();
 
@@ -979,21 +978,21 @@ mod tests {
 	#[should_panic(expected = "bad target index")]
 	fn retracting_inactive_voter_with_bad_target_index_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 8, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Eve).set_approvals(vec![true], 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 38, 1);
 			internal::end_block();
 
@@ -1008,7 +1007,7 @@ mod tests {
 	#[test]
 	fn attempting_to_retract_active_voter_should_slash_reporter() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Charlie).submit_candidacy(1);
 			PublicPass::test(&Dave).submit_candidacy(2);
@@ -1019,18 +1018,18 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, false, false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			PublicPass::test(&Dave).present_winner(Charlie.into(), 21, 0);
 			PublicPass::test(&Dave).present_winner(Dave.into(), 31, 0);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PrivPass::test().set_desired_seats(3);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 1);
 			PublicPass::test(&Dave).present_winner(Charlie.into(), 21, 1);
 			internal::end_block();
@@ -1051,21 +1050,21 @@ mod tests {
 	#[should_panic(expected = "reaper must be a voter")]
 	fn attempting_to_retract_inactive_voter_by_nonvoter_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Bob).set_approvals(vec![true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Eve).submit_candidacy(0);
 			PublicPass::test(&Eve).set_approvals(vec![true], 1);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 1);
 			internal::end_block();
 
@@ -1081,7 +1080,7 @@ mod tests {
 	#[should_panic(expected = "candidate not worthy of leaderboard")]
 	fn presenting_loser_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Alice).submit_candidacy(0);
 			PublicPass::test(&Ferdie).set_approvals(vec![true], 0);
 			PublicPass::test(&Bob).submit_candidacy(1);
@@ -1094,7 +1093,7 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, false, false, false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Alice.into(), 60, 0);
 			PublicPass::test(&Dave).present_winner(Charlie.into(), 21, 0);
 			PublicPass::test(&Dave).present_winner(Dave.into(), 31, 0);
@@ -1106,7 +1105,7 @@ mod tests {
 	#[test]
 	fn presenting_loser_first_should_not_matter() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Alice).submit_candidacy(0);
 			PublicPass::test(&Ferdie).set_approvals(vec![true], 0);
 			PublicPass::test(&Bob).submit_candidacy(1);
@@ -1119,7 +1118,7 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, false, false, false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 0);
 			PublicPass::test(&Dave).present_winner(Alice.into(), 60, 0);
 			PublicPass::test(&Dave).present_winner(Charlie.into(), 21, 0);
@@ -1139,7 +1138,7 @@ mod tests {
 	#[should_panic(expected = "cannot present outside of presentation period")]
 	fn present_panics_outside_of_presentation_period() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			assert!(!presentation_active());
 			PublicPass::test(&Eve).present_winner(Eve.into(), 1, 0);
 		});
@@ -1149,14 +1148,14 @@ mod tests {
 	#[should_panic(expected = "index not current")]
 	fn present_panics_with_invalid_vote_index() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Bob).submit_candidacy(0);
 			PublicPass::test(&Eve).submit_candidacy(1);
 			PublicPass::test(&Bob).set_approvals(vec![true, false], 0);
 			PublicPass::test(&Eve).set_approvals(vec![false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 11, 1);
 		});
 	}
@@ -1165,7 +1164,7 @@ mod tests {
 	#[should_panic(expected = "presenter must have sufficient slashable funds")]
 	fn present_panics_when_presenter_is_poor() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			assert!(!presentation_active());
 
 			PublicPass::test(&Alice).submit_candidacy(0);
@@ -1174,7 +1173,7 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			assert_eq!(staking::balance(&Alice), 1);
 			PublicPass::test(&Alice).present_winner(Alice.into(), 30, 0);
 		});
@@ -1183,7 +1182,7 @@ mod tests {
 	#[test]
 	fn invalid_present_tally_should_slash() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			assert!(!presentation_active());
 			assert_eq!(staking::balance(&Dave), 40);
 
@@ -1193,7 +1192,7 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Bob.into(), 80, 0);
 
 			assert_eq!(staking::balance(&Dave), 38);
@@ -1203,7 +1202,7 @@ mod tests {
 	#[test]
 	fn runners_up_should_be_kept() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			assert!(!presentation_active());
 
 			PublicPass::test(&Alice).submit_candidacy(0);
@@ -1219,7 +1218,7 @@ mod tests {
 
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			assert!(presentation_active());
 			PublicPass::test(&Dave).present_winner(Alice.into(), 60, 0);
 			assert_eq!(leaderboard(), Some(vec![
@@ -1262,7 +1261,7 @@ mod tests {
 	#[test]
 	fn second_tally_should_use_runners_up() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PublicPass::test(&Alice).submit_candidacy(0);
 			PublicPass::test(&Ferdie).set_approvals(vec![true], 0);
 			PublicPass::test(&Bob).submit_candidacy(1);
@@ -1275,19 +1274,19 @@ mod tests {
 			PublicPass::test(&Eve).set_approvals(vec![false, false, false, false, true], 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			PublicPass::test(&Dave).present_winner(Alice.into(), 60, 0);
 			PublicPass::test(&Dave).present_winner(Charlie.into(), 21, 0);
 			PublicPass::test(&Dave).present_winner(Dave.into(), 31, 0);
 			PublicPass::test(&Dave).present_winner(Eve.into(), 41, 0);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			PublicPass::test(&Ferdie).set_approvals(vec![false, false, true, false], 1);
 			PrivPass::test().set_desired_seats(3);
 			internal::end_block();
 
-			with_env(|e| e.block_number = 10);
+			system::testing::set_block_number(10);
 			PublicPass::test(&Dave).present_winner(Charlie.into(), 81, 1);
 			PublicPass::test(&Dave).present_winner(Dave.into(), 31, 1);
 			internal::end_block();

substrate/demo/runtime/src/runtime/council_vote.rs

@@ -228,7 +228,6 @@ mod tests {
 	use runtime_io::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
 	use keyring::Keyring::{Alice, Bob, Charlie, Dave};
-	use environment::with_env;
 	use demo_primitives::AccountId;
 	use runtime::democracy::VoteThreshold;
 	use runtime::{staking, council, democracy};
@@ -242,7 +241,7 @@ mod tests {
 	#[test]
 	fn basic_environment_works() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(staking::bonding_duration(), 0);
 			assert_eq!(cooloff_period(), 2);
 			assert_eq!(voting_period(), 1);
@@ -274,7 +273,7 @@ mod tests {
 	#[test]
 	fn referendum_cancellation_should_work_when_unanimous() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			democracy::internal::start_referendum(proposal.clone(), VoteThreshold::SuperMajorityApprove);
 			assert_eq!(democracy::active_referendums(), vec![(0, 4, proposal, VoteThreshold::SuperMajorityApprove)]);
@@ -287,7 +286,7 @@ mod tests {
 			assert_eq!(proposals(), vec![(2, hash)]);
 			internal::end_block(1);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			internal::end_block(2);
 			assert_eq!(democracy::active_referendums(), vec![]);
 			assert_eq!(staking::bonding_duration(), 0);
@@ -297,7 +296,7 @@ mod tests {
 	#[test]
 	fn referendum_cancellation_should_fail_when_not_unanimous() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			democracy::internal::start_referendum(proposal.clone(), VoteThreshold::SuperMajorityApprove);
 
@@ -308,7 +307,7 @@ mod tests {
 			PublicPass::new(&Charlie).vote(hash, false);
 			internal::end_block(1);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			internal::end_block(2);
 			assert_eq!(democracy::active_referendums(), vec![(0, 4, proposal, VoteThreshold::SuperMajorityApprove)]);
 		});
@@ -317,7 +316,7 @@ mod tests {
 	#[test]
 	fn referendum_cancellation_should_fail_when_abstentions() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			democracy::internal::start_referendum(proposal.clone(), VoteThreshold::SuperMajorityApprove);
 
@@ -327,7 +326,7 @@ mod tests {
 			PublicPass::new(&Bob).vote(hash, true);
 			internal::end_block(1);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			internal::end_block(2);
 			assert_eq!(democracy::active_referendums(), vec![(0, 4, proposal, VoteThreshold::SuperMajorityApprove)]);
 		});
@@ -336,7 +335,7 @@ mod tests {
 	#[test]
 	fn veto_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			let hash = proposal.blake2_256();
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
@@ -350,13 +349,13 @@ mod tests {
 	#[should_panic]
 	fn double_veto_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			let hash = proposal.blake2_256();
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).veto(hash);
 
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).veto(hash);
 		});
@@ -366,13 +365,13 @@ mod tests {
 	#[should_panic]
 	fn retry_in_cooloff_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			let hash = proposal.blake2_256();
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).veto(hash);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 		});
 	}
@@ -380,19 +379,19 @@ mod tests {
 	#[test]
 	fn retry_after_cooloff_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			let hash = proposal.blake2_256();
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).veto(hash);
 
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).vote(hash, false);
 			PublicPass::new(&Charlie).vote(hash, true);
 			internal::end_block(3);
 
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			internal::end_block(4);
 			assert_eq!(proposals().len(), 0);
 			assert_eq!(democracy::active_referendums(), vec![(0, 7, bonding_duration_proposal(42), VoteThreshold::SimpleMajority)]);
@@ -402,13 +401,13 @@ mod tests {
 	#[test]
 	fn alternative_double_veto_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			let hash = proposal.blake2_256();
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).veto(hash);
 
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Charlie).veto(hash);
 			assert_eq!(proposals().len(), 0);
@@ -419,7 +418,7 @@ mod tests {
 	#[test]
 	fn simple_propose_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			let hash = proposal.blake2_256();
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
@@ -433,13 +432,13 @@ mod tests {
 	#[test]
 	fn unvoted_proposal_should_expire_without_action() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			assert_eq!(tally(&proposal.blake2_256()), (1, 0, 2));
 			internal::end_block(1);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			internal::end_block(2);
 			assert_eq!(proposals().len(), 0);
 			assert_eq!(democracy::active_referendums().len(), 0);
@@ -449,7 +448,7 @@ mod tests {
 	#[test]
 	fn unanimous_proposal_should_expire_with_biased_referendum() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).vote(proposal.blake2_256(), true);
@@ -457,7 +456,7 @@ mod tests {
 			assert_eq!(tally(&proposal.blake2_256()), (3, 0, 0));
 			internal::end_block(1);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			internal::end_block(2);
 			assert_eq!(proposals().len(), 0);
 			assert_eq!(democracy::active_referendums(), vec![(0, 5, proposal, VoteThreshold::SuperMajorityAgainst)]);
@@ -467,7 +466,7 @@ mod tests {
 	#[test]
 	fn majority_proposal_should_expire_with_unbiased_referendum() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			PublicPass::new(&Alice).propose(Box::new(proposal.clone()));
 			PublicPass::new(&Bob).vote(proposal.blake2_256(), true);
@@ -475,7 +474,7 @@ mod tests {
 			assert_eq!(tally(&proposal.blake2_256()), (2, 1, 0));
 			internal::end_block(1);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			internal::end_block(2);
 			assert_eq!(proposals().len(), 0);
 			assert_eq!(democracy::active_referendums(), vec![(0, 5, proposal, VoteThreshold::SimpleMajority)]);
@@ -486,7 +485,7 @@ mod tests {
 	#[should_panic]
 	fn propose_by_public_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let proposal = bonding_duration_proposal(42);
 			PublicPass::new(&Dave).propose(Box::new(proposal));
 		});

substrate/demo/runtime/src/runtime/democracy.rs

@@ -348,7 +348,6 @@ mod tests {
 	use runtime_io::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
 	use keyring::Keyring::*;
-	use environment::with_env;
 	use demo_primitives::AccountId;
 	use dispatch::PrivCall as Proposal;
 	use runtime::staking::PublicPass;
@@ -382,7 +381,7 @@ mod tests {
 	#[test]
 	fn locked_for_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Alice, 2, 2u64);
 			propose_sessions_per_era(&Alice, 4, 4u64);
 			propose_sessions_per_era(&Alice, 3, 3u64);
@@ -395,11 +394,11 @@ mod tests {
 	#[test]
 	fn single_proposal_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Alice, 2, 1u64);
 			democracy::internal::end_block(system::block_number());
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			let r = 0;
 			PublicPass::test(&Alice).vote(r, true);
 
@@ -418,7 +417,7 @@ mod tests {
 	#[test]
 	fn deposit_for_proposals_should_be_taken() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Alice, 2, 5u64);
 			PublicPass::test(&Bob).second(0);
 			PublicPass::test(&Eve).second(0);
@@ -433,7 +432,7 @@ mod tests {
 	#[test]
 	fn deposit_for_proposals_should_be_returned() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Alice, 2, 5u64);
 			PublicPass::test(&Bob).second(0);
 			PublicPass::test(&Eve).second(0);
@@ -450,7 +449,7 @@ mod tests {
 	#[should_panic]
 	fn proposal_with_deposit_below_minimum_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Alice, 2, 0u64);
 		});
 	}
@@ -459,7 +458,7 @@ mod tests {
 	#[should_panic]
 	fn poor_proposer_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Alice, 2, 11u64);
 		});
 	}
@@ -468,7 +467,7 @@ mod tests {
 	#[should_panic]
 	fn poor_seconder_should_panic() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			propose_sessions_per_era(&Bob, 2, 11u64);
 			PublicPass::test(&Alice).second(0);
 		});
@@ -482,25 +481,25 @@ mod tests {
 	#[test]
 	fn runners_up_should_come_after() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 0);
+			system::testing::set_block_number(0);
 			propose_bonding_duration(&Alice, 2, 2u64);
 			propose_bonding_duration(&Alice, 4, 4u64);
 			propose_bonding_duration(&Alice, 3, 3u64);
 			democracy::internal::end_block(system::block_number());
 
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			PublicPass::test(&Alice).vote(0, true);
 			democracy::internal::end_block(system::block_number());
 			staking::internal::check_new_era();
 			assert_eq!(staking::bonding_duration(), 4u64);
 
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			PublicPass::test(&Alice).vote(1, true);
 			democracy::internal::end_block(system::block_number());
 			staking::internal::check_new_era();
 			assert_eq!(staking::bonding_duration(), 3u64);
 
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PublicPass::test(&Alice).vote(2, true);
 			democracy::internal::end_block(system::block_number());
 			staking::internal::check_new_era();
@@ -515,7 +514,7 @@ mod tests {
 	#[test]
 	fn simple_passing_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let r = inject_referendum(1, sessions_per_era_propsal(2), VoteThreshold::SuperMajorityApprove);
 			PublicPass::test(&Alice).vote(r, true);
 
@@ -533,10 +532,10 @@ mod tests {
 	#[test]
 	fn cancel_referendum_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let r = inject_referendum(1, sessions_per_era_propsal(2), VoteThreshold::SuperMajorityApprove);
 			PublicPass::test(&Alice).vote(r, true);
-			PrivPass::new().cancel_referendum(r);
+			PrivPass::test().cancel_referendum(r);
 
 			democracy::internal::end_block(system::block_number());
 			staking::internal::check_new_era();
@@ -548,7 +547,7 @@ mod tests {
 	#[test]
 	fn simple_failing_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let r = inject_referendum(1, sessions_per_era_propsal(2), VoteThreshold::SuperMajorityApprove);
 			PublicPass::test(&Alice).vote(r, false);
 
@@ -566,7 +565,7 @@ mod tests {
 	#[test]
 	fn controversial_voting_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let r = inject_referendum(1, sessions_per_era_propsal(2), VoteThreshold::SuperMajorityApprove);
 			PublicPass::test(&Alice).vote(r, true);
 			PublicPass::test(&Bob).vote(r, false);
@@ -587,7 +586,7 @@ mod tests {
 	#[test]
 	fn controversial_low_turnout_voting_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let r = inject_referendum(1, sessions_per_era_propsal(2), VoteThreshold::SuperMajorityApprove);
 			PublicPass::test(&Eve).vote(r, false);
 			PublicPass::test(&Ferdie).vote(r, true);
@@ -607,7 +606,7 @@ mod tests {
 			assert_eq!(staking::era_length(), 1u64);
 			assert_eq!(staking::total_stake(), 210u64);
 
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			let r = inject_referendum(1, sessions_per_era_propsal(2), VoteThreshold::SuperMajorityApprove);
 			PublicPass::test(&Dave).vote(r, true);
 			PublicPass::test(&Eve).vote(r, false);

substrate/demo/runtime/src/runtime/session.rs

@@ -151,7 +151,6 @@ mod tests {
 	use runtime_io::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
 	use keyring::Keyring;
-	use environment::with_env;
 	use demo_primitives::AccountId;
 	use runtime::{consensus, session};
 
@@ -183,46 +182,46 @@ mod tests {
 		let mut t = simple_setup();
 		with_externalities(&mut t, || {
 			// Block 1: Change to length 3; no visible change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			PrivPass::test().set_length(3);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 0);
 
 			// Block 2: Length now changed to 3. Index incremented.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			PrivPass::test().set_length(3);
 			check_rotate_session();
 			assert_eq!(length(), 3);
 			assert_eq!(current_index(), 1);
 
 			// Block 3: Length now changed to 3. Index incremented.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			check_rotate_session();
 			assert_eq!(length(), 3);
 			assert_eq!(current_index(), 1);
 
 			// Block 4: Change to length 2; no visible change.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			PrivPass::test().set_length(2);
 			check_rotate_session();
 			assert_eq!(length(), 3);
 			assert_eq!(current_index(), 1);
 
 			// Block 5: Length now changed to 2. Index incremented.
-			with_env(|e| e.block_number = 5);
+			system::testing::set_block_number(5);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 2);
 
 			// Block 6: No change.
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 2);
 
 			// Block 7: Next index.
-			with_env(|e| e.block_number = 7);
+			system::testing::set_block_number(7);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 3);
@@ -234,17 +233,17 @@ mod tests {
 		let mut t = simple_setup();
 		with_externalities(&mut t, || {
 			// Block 1: No change
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 2: Session rollover, but no change.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 3: Set new key for validator 2; no visible change.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PublicPass::test(&[20; 32]).set_key([22; 32]);
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
@@ -252,7 +251,7 @@ mod tests {
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 4: Session rollover, authority 2 changes.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [22u8; 32]]);
 		});

substrate/demo/runtime/src/runtime/staking.rs

@@ -569,7 +569,6 @@ mod tests {
 	use runtime_io::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
 	use keyring::Keyring::*;
-	use environment::with_env;
 	use demo_primitives::AccountId;
 	use runtime::{staking, session};
 	use runtime::democracy::PrivPass;
@@ -600,7 +599,7 @@ mod tests {
 			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
 
 			// Block 1: Add three validators. No obvious change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::Call::stake().dispatch(PublicPass::new(&Alice));
 			PublicPass::new(&Bob).stake();
 			PublicPass::new(&Dave).stake();
@@ -608,39 +607,39 @@ mod tests {
 			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
 
 			// Block 2: New validator set now.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			check_new_era();
 			assert_eq!(session::validators(), vec![Dave.to_raw_public(), Bob.into()]);
 
 			// Block 3: Unstake highest, introduce another staker. No change yet.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PublicPass::new(&Charlie).stake();
 			PublicPass::new(&Dave).unstake();
 			check_new_era();
 
 			// Block 4: New era - validators change.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			check_new_era();
 			assert_eq!(session::validators(), vec![Charlie.to_raw_public(), Bob.into()]);
 
 			// Block 5: Transfer stake from highest to lowest. No change yet.
-			with_env(|e| e.block_number = 5);
+			system::testing::set_block_number(5);
 			PublicPass::new(&Dave).transfer(Alice.to_raw_public(), 40);
 			check_new_era();
 
 			// Block 6: Lowest now validator.
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			check_new_era();
 			assert_eq!(session::validators(), vec![Alice.to_raw_public(), Charlie.into()]);
 
 			// Block 7: Unstake three. No change yet.
-			with_env(|e| e.block_number = 7);
+			system::testing::set_block_number(7);
 			PublicPass::new(&Charlie).unstake();
 			check_new_era();
 			assert_eq!(session::validators(), vec![Alice.to_raw_public(), Charlie.into()]);
 
 			// Block 8: Back to one and two.
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			check_new_era();
 			assert_eq!(session::validators(), vec![Alice.to_raw_public(), Bob.into()]);
 		});
@@ -661,21 +660,21 @@ mod tests {
 			assert_eq!(CurrentEra::get(), 0u64);
 
 			// Block 1: No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 2u64);
 			assert_eq!(LastEraLengthChange::get(), 0u64);
 			assert_eq!(CurrentEra::get(), 0u64);
 
 			// Block 2: Simple era change.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 2u64);
 			assert_eq!(LastEraLengthChange::get(), 0u64);
 			assert_eq!(CurrentEra::get(), 1u64);
 
 			// Block 3: Schedule an era length change; no visible changes.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			PrivPass::test().set_sessions_per_era(3);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 2u64);
@@ -683,28 +682,28 @@ mod tests {
 			assert_eq!(CurrentEra::get(), 1u64);
 
 			// Block 4: Era change kicks in.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 3u64);
 			assert_eq!(LastEraLengthChange::get(), 4u64);
 			assert_eq!(CurrentEra::get(), 2u64);
 
 			// Block 5: No change.
-			with_env(|e| e.block_number = 5);
+			system::testing::set_block_number(5);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 3u64);
 			assert_eq!(LastEraLengthChange::get(), 4u64);
 			assert_eq!(CurrentEra::get(), 2u64);
 
 			// Block 6: No change.
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 3u64);
 			assert_eq!(LastEraLengthChange::get(), 4u64);
 			assert_eq!(CurrentEra::get(), 2u64);
 
 			// Block 7: Era increment.
-			with_env(|e| e.block_number = 7);
+			system::testing::set_block_number(7);
 			check_new_era();
 			assert_eq!(SessionsPerEra::get(), 3u64);
 			assert_eq!(LastEraLengthChange::get(), 4u64);
@@ -714,7 +713,7 @@ mod tests {
 
 	#[test]
 	fn staking_balance_works() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 42);
 			assert_eq!(FreeBalanceOf::get(*Alice), 42);
 			assert_eq!(ReservedBalanceOf::get(*Alice), 0);
@@ -738,7 +737,7 @@ mod tests {
 	#[test]
 	#[should_panic]
 	fn staking_balance_transfer_when_bonded_panics() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			PublicPass::new(&Alice).stake();
 			PublicPass::new(&Alice).transfer(Bob.to_raw_public(), 69);
@@ -747,7 +746,7 @@ mod tests {
 
 	#[test]
 	fn reserving_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 
 			assert_eq!(balance(&Alice), 111);
@@ -765,7 +764,7 @@ mod tests {
 	#[test]
 	#[should_panic]
 	fn staking_balance_transfer_when_reserved_panics() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 69);
 			PublicPass::new(&Alice).transfer(Bob.to_raw_public(), 69);
@@ -774,7 +773,7 @@ mod tests {
 
 	#[test]
 	fn deducting_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			assert!(deduct_unbonded(&Alice, 69));
 			assert_eq!(FreeBalanceOf::get(*Alice), 42);
@@ -788,7 +787,7 @@ mod tests {
 			twox_128(&BondageOf::key_for(*Alice)).to_vec() => vec![].and(&2u64)
 		];
 		with_externalities(&mut t, || {
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			assert_eq!(unlock_block(&Alice), LockStatus::LockedUntil(2));
 			assert!(!deduct_unbonded(&Alice, 69));
 		});
@@ -796,7 +795,7 @@ mod tests {
 
 	#[test]
 	fn refunding_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 42);
 			refund(&Alice, 69);
 			assert_eq!(FreeBalanceOf::get(*Alice), 111);
@@ -805,7 +804,7 @@ mod tests {
 
 	#[test]
 	fn slashing_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 69);
 			assert!(slash(&Alice, 69));
@@ -816,7 +815,7 @@ mod tests {
 
 	#[test]
 	fn slashing_incomplete_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 42);
 			reserve_balance(&Alice, 21);
 			assert!(!slash(&Alice, 69));
@@ -827,7 +826,7 @@ mod tests {
 
 	#[test]
 	fn unreserving_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 111);
 			unreserve_balance(&Alice, 42);
@@ -838,7 +837,7 @@ mod tests {
 
 	#[test]
 	fn slashing_reserved_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 111);
 			assert!(slash_reserved(&Alice, 42));
@@ -849,7 +848,7 @@ mod tests {
 
 	#[test]
 	fn slashing_incomplete_reserved_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 42);
 			assert!(!slash_reserved(&Alice, 69));
@@ -860,7 +859,7 @@ mod tests {
 
 	#[test]
 	fn transferring_reserved_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 111);
 			assert!(transfer_reserved_balance(&Alice, &Bob, 42));
@@ -873,7 +872,7 @@ mod tests {
 
 	#[test]
 	fn transferring_incomplete_reserved_balance_should_work() {
-		with_externalities(&mut TestExternalities::default(), || {
+		with_externalities(&mut testing::externalities(1, 3, 1), || {
 			FreeBalanceOf::insert(*Alice, 111);
 			reserve_balance(&Alice, 42);
 			assert!(!transfer_reserved_balance(&Alice, &Bob, 69));

substrate/demo/runtime/src/runtime/system.rs

@@ -22,27 +22,27 @@ use rstd::mem;
 use runtime_io::{print, storage_root, enumerated_trie_root};
 use codec::{KeyedVec, Slicable};
 use runtime_support::{Hashable, storage, StorageValue, StorageMap};
-use environment::with_env;
 use demo_primitives::{AccountId, Hash, TxOrder, BlockNumber, Header, Log};
-use block::Block;
+use block::{self, Block};
 use transaction::UncheckedTransaction;
 use runtime::{staking, session};
 use runtime::democracy::PrivPass;
 use dispatch;
+use safe_mix::TripletMix;
 
 storage_items! {
-	pub Nonce: b"sys:non" => default map [ AccountId => TxOrder ];
+	pub Nonce get(nonce): b"sys:non" => default map [ AccountId => TxOrder ];
-	pub BlockHashAt: b"sys:old" => required map [ BlockNumber => Hash ];
+	pub BlockHashAt get(block_hash): b"sys:old" => required map [ BlockNumber => Hash ];
+	RandomSeed get(random_seed): b"sys:rnd" => required Hash;
+	// The current block number being processed. Set by `execute_block`.
+	Number get(block_number): b"sys:num" => required BlockNumber;
+	ParentHash get(parent_hash): b"sys:pha" => required Hash;
+	TransactionsRoot get(transactions_root): b"sys:txr" => required Hash;
+	Digest: b"sys:dig" => default block::Digest;
 }
 
 pub const CODE: &'static[u8] = b":code";
 
-
-/// The current block number being processed. Set by `execute_block`.
-pub fn block_number() -> BlockNumber {
-	with_env(|e| e.block_number)
-}
-
 impl_dispatch! {
 	pub mod privileged;
 	fn set_code(new: Vec<u8>) = 0;
@@ -51,7 +51,7 @@ impl_dispatch! {
 impl privileged::Dispatch for PrivPass {
 	/// Set the new code.
 	fn set_code(self, new: Vec<u8>) {
-		storage::unhashed::put_raw(b":code", &new);
+		storage::unhashed::put_raw(CODE, &new);
 	}
 }
 
@@ -62,16 +62,14 @@ pub mod internal {
 
 	/// Deposits a log and ensures it matches the blocks log data.
 	pub fn deposit_log(log: Log) {
-		with_env(|e| e.digest.logs.push(log));
+		let mut l = Digest::get();
+		l.logs.push(log);
+		Digest::put(l);
 	}
 
 	/// Actually execute all transitioning for `block`.
 	pub fn execute_block(mut block: Block) {
-		// populate environment from header.
+		initialise_block(&block.header);
-		with_env(|e| {
-			e.block_number = block.header.number;
-			e.parent_hash = block.header.parent_hash;
-		});
 
 		// any initial checks
 		initial_checks(&block);
@@ -90,41 +88,35 @@ pub mod internal {
 		post_finalise(&block.header);
 	}
 
+	/// Start the execution of a particular block.
+	pub fn initialise_block(mut header: &Header) {
+		// populate environment from header.
+		Number::put(header.number);
+		ParentHash::put(header.parent_hash);
+		TransactionsRoot::put(header.transaction_root);
+		RandomSeed::put(calculate_random());
+	}
+
 	/// Execute a transaction outside of the block execution function.
 	/// This doesn't attempt to validate anything regarding the block.
-	pub fn execute_transaction(utx: UncheckedTransaction, mut header: Header) -> Header {
+	pub fn execute_transaction(utx: UncheckedTransaction) {
-		// populate environment from header.
-		with_env(|e| {
-			e.block_number = header.number;
-			e.parent_hash = header.parent_hash;
-			mem::swap(&mut header.digest, &mut e.digest);
-		});
-
 		super::execute_transaction(utx);
-
-		with_env(|e| {
-			mem::swap(&mut header.digest, &mut e.digest);
-		});
-		header
 	}
 
 	/// Finalise the block - it is up the caller to ensure that all header fields are valid
 	/// except state-root.
-	pub fn finalise_block(mut header: Header) -> Header {
+	pub fn finalise_block() -> Header {
-		// populate environment from header.
-		with_env(|e| {
-			e.block_number = header.number;
-			e.parent_hash = header.parent_hash;
-			mem::swap(&mut header.digest, &mut e.digest);
-		});
-
 		staking::internal::check_new_era();
 		session::internal::check_rotate_session();
 
-		header.state_root = storage_root().into();
+		RandomSeed::kill();
-		with_env(|e| {
+		let header = Header {
-			mem::swap(&mut header.digest, &mut e.digest);
+			number: Number::take(),
-		});
+			digest: Digest::take(),
+			parent_hash: ParentHash::take(),
+			transaction_root: TransactionsRoot::take(),
+			state_root: storage_root().into(),
+		};
 
 		post_finalise(&header);
 
@@ -176,9 +168,10 @@ fn final_checks(block: &Block) {
 	let ref header = block.header;
 
 	// check digest
-	with_env(|e| {
+	assert!(header.digest == Digest::get());
-		assert!(header.digest == e.digest);
+
-	});
+	// remove temporaries.
+	kill_temps();
 
 	// check storage root.
 	let storage_root = storage_root().into();
@@ -186,12 +179,27 @@ fn final_checks(block: &Block) {
 	assert!(header.state_root == storage_root, "Storage root must match that calculated.");
 }
 
+fn kill_temps() {
+	Number::kill();
+	ParentHash::kill();
+	RandomSeed::kill();
+	Digest::kill();
+	TransactionsRoot::kill();
+}
+
 fn post_finalise(header: &Header) {
 	// store the header hash in storage; we can't do it before otherwise there would be a
 	// cyclic dependency.
 	BlockHashAt::insert(&header.number, &header.blake2_256().into());
 }
 
+fn calculate_random() -> Hash {
+	let c = block_number() - 1;
+	(0..81)
+		.map(|i| if c >= i { block_hash(c - i) } else { Default::default() })
+		.triplet_mix()
+}
+
 #[cfg(feature = "std")]
 fn info_expect_equal_hash(given: &Hash, expected: &Hash) {
 	use primitives::hexdisplay::HexDisplay;
@@ -217,9 +225,16 @@ pub mod testing {
 
 	pub fn externalities() -> TestExternalities {
 		map![
-			twox_128(&BlockHashAt::key_for(&0)).to_vec() => [69u8; 32].encode()
+			twox_128(&BlockHashAt::key_for(&0)).to_vec() => [69u8; 32].encode(),
+			twox_128(Number::key()).to_vec() => 1u64.encode(),
+			twox_128(ParentHash::key()).to_vec() => [69u8; 32].encode(),
+			twox_128(RandomSeed::key()).to_vec() => [0u8; 32].encode()
 		]
 	}
+
+	pub fn set_block_number(n: BlockNumber) {
+		Number::put(n);
+	}
 }
 
 #[cfg(test)]
@@ -231,7 +246,6 @@ mod tests {
 	use runtime_support::StorageValue;
 	use codec::{Joiner, KeyedVec, Slicable};
 	use keyring::Keyring::*;
-	use environment::with_env;
 	use primitives::hexdisplay::HexDisplay;
 	use demo_primitives::{Header, Digest};
 	use transaction::{UncheckedTransaction, Transaction};
@@ -243,7 +257,8 @@ mod tests {
 	fn staking_balance_transfer_dispatch_works() {
 		let mut t: TestExternalities = map![
 			twox_128(&staking::FreeBalanceOf::key_for(*One)).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0],
-			twox_128(staking::TransactionFee::key()).to_vec() => vec![10u8, 0, 0, 0, 0, 0, 0, 0]
+			twox_128(staking::TransactionFee::key()).to_vec() => vec![10u8, 0, 0, 0, 0, 0, 0, 0],
+			twox_128(&BlockHashAt::key_for(&0)).to_vec() => [69u8; 32].encode()
 		];
 
 		let tx = UncheckedTransaction {
@@ -256,7 +271,8 @@ mod tests {
 		};
 
 		with_externalities(&mut t, || {
-			internal::execute_transaction(tx, Header::from_block_number(1));
+			internal::initialise_block(&Header::from_block_number(1));
+			internal::execute_transaction(tx);
 			assert_eq!(staking::balance(&One), 32);
 			assert_eq!(staking::balance(&Two), 69);
 		});

substrate/demo/runtime/src/safe_mix.rs

@@ -0,0 +1,138 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Substrate Demo.
+
+// Substrate Demo 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 Demo 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 Demo.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Means of mixing a series of hashes to create a single secure hash.
+//!
+//! Described in http://www.cs.huji.ac.il/~nati/PAPERS/coll_coin_fl.pdf
+
+use rstd::ops::{BitAnd, BitOr};
+
+pub const MAX_DEPTH: usize = 17;
+
+fn sub_mix<T>(seeds: &[T]) -> T where
+	T: BitAnd<Output = T> + BitOr<Output = T> + Copy
+{
+	(seeds[0] & seeds[1]) | (seeds[1] & seeds[2]) | (seeds[0] & seeds[2])
+}
+
+/// Mix a slice.
+pub fn triplet_mix<T>(seeds: &[T]) -> Result<T, ()> where
+	T: BitAnd<Output = T> + BitOr<Output = T>,
+	T: Default + Copy
+{
+	Ok(seeds.iter().cloned().triplet_mix())
+}
+
+/// The mixed trait for mixing a sequence.
+pub trait TripletMix {
+	/// The items in the sequence and simultaneously the return of the mixing.
+	type Item;
+	/// The output of the mixing algorithm on the sequence. Items in the sequence beyond
+	/// the largest power of three that fits within the the sequence up until `3 ** MAX_DEPTH`
+	/// are ignored.
+	fn triplet_mix(self) -> Self::Item;
+}
+
+impl<I, T> TripletMix for I where
+	I: Iterator<Item = T>,
+	T: BitAnd<Output = T> + BitOr<Output = T> + Default + Copy
+{
+	type Item = T;
+	fn triplet_mix(self) -> Self::Item {
+		let mut accum = [[T::default(); 3]; MAX_DEPTH];
+		let mut result = T::default();
+		for (i, seed) in self.enumerate() {
+			accum[0][i % 3] = seed;
+			let mut index_at_depth = i;
+			for depth in 0..MAX_DEPTH {
+				if index_at_depth % 3 != 2 {
+					break;
+				}
+				index_at_depth /= 3;
+				result = sub_mix(&accum[depth]);
+
+				// end of the threesome at depth.
+				if depth == MAX_DEPTH - 1 {
+					// end of our stack - bail with result.
+					break;
+				} else {
+					// save in the stack for parent computation
+					accum[depth + 1][index_at_depth % 3] = result;
+				}
+			}
+		}
+		result
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	#[test]
+	fn sub_mix_works() {
+		assert_eq!(sub_mix(&[0, 0, 0][..]), 0);
+		assert_eq!(sub_mix(&[0, 0, 1][..]), 0);
+		assert_eq!(sub_mix(&[0, 1, 0][..]), 0);
+		assert_eq!(sub_mix(&[0, 1, 1][..]), 1);
+		assert_eq!(sub_mix(&[1, 0, 0][..]), 0);
+		assert_eq!(sub_mix(&[1, 0, 1][..]), 1);
+		assert_eq!(sub_mix(&[1, 1, 0][..]), 1);
+		assert_eq!(sub_mix(&[1, 1, 1][..]), 1);
+
+		assert_eq!(sub_mix(&[0, 0, 0][..]), 0);
+		assert_eq!(sub_mix(&[0, 0, 2][..]), 0);
+		assert_eq!(sub_mix(&[0, 2, 0][..]), 0);
+		assert_eq!(sub_mix(&[0, 2, 2][..]), 2);
+		assert_eq!(sub_mix(&[2, 0, 0][..]), 0);
+		assert_eq!(sub_mix(&[2, 0, 2][..]), 2);
+		assert_eq!(sub_mix(&[2, 2, 0][..]), 2);
+		assert_eq!(sub_mix(&[2, 2, 2][..]), 2);
+	}
+
+	#[test]
+	fn triplet_mix_works_on_first_level() {
+		assert_eq!(triplet_mix(&[0, 0, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 0, 1][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 1, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 1, 1][..]).unwrap(), 1);
+		assert_eq!(triplet_mix(&[1, 0, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[1, 0, 1][..]).unwrap(), 1);
+		assert_eq!(triplet_mix(&[1, 1, 0][..]).unwrap(), 1);
+		assert_eq!(triplet_mix(&[1, 1, 1][..]).unwrap(), 1);
+
+		assert_eq!(triplet_mix(&[0, 0, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 0, 2][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 2, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 2, 2][..]).unwrap(), 2);
+		assert_eq!(triplet_mix(&[2, 0, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[2, 0, 2][..]).unwrap(), 2);
+		assert_eq!(triplet_mix(&[2, 2, 0][..]).unwrap(), 2);
+		assert_eq!(triplet_mix(&[2, 2, 2][..]).unwrap(), 2);
+	}
+
+	#[test]
+	fn triplet_mix_works_on_second_level() {
+		assert_eq!(triplet_mix(&[0, 0, 0, 0, 0, 1, 0, 1, 0][..]).unwrap(), 0);
+		assert_eq!(triplet_mix(&[0, 1, 1, 1, 0, 0, 1, 0, 1][..]).unwrap(), 1);
+		assert_eq!(triplet_mix(&[1, 1, 0, 1, 1, 1, 0, 0, 0][..]).unwrap(), 1);
+	}
+
+	#[test]
+	fn triplet_mix_works_on_third_level() {
+		assert_eq!(triplet_mix(&[0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0][..]).unwrap(), 1);
+	}
+}

substrate/polkadot/runtime/src/runtime/governance.rs

@@ -189,7 +189,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Approve it. Era length changes.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			public::approve(&two, 1);
 			staking::internal::check_new_era();
@@ -212,13 +212,13 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Fail it.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			staking::internal::check_new_era();
 			assert_eq!(staking::era_length(), 1);
 
 			// Block 2: Make proposal. Approve it. It should change era length.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			public::approve(&two, 2);
 			staking::internal::check_new_era();
@@ -241,7 +241,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Will have only 1 vote. No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			staking::internal::check_new_era();
 			assert_eq!(staking::era_length(), 1);
@@ -264,7 +264,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Will have only 1 vote. No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			public::approve(&two, 0);
 			staking::internal::check_new_era();
@@ -288,7 +288,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Will have only 1 vote. No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			public::approve(&two, 1);
 			public::approve(&two, 1);
@@ -313,7 +313,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Will have only 1 vote. No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			public::propose(&two, &Proposal::StakingSetSessionsPerEra(2));
 			staking::internal::check_new_era();
@@ -337,7 +337,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Will have only 1 vote. No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::approve(&two, 1);
 			staking::internal::check_new_era();
 			assert_eq!(staking::era_length(), 1);
@@ -361,7 +361,7 @@ mod tests {
 			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
 
 			// Block 1: Make proposal. Will have only 1 vote. No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			public::propose(&one, &Proposal::StakingSetSessionsPerEra(2));
 			public::approve(&four, 1);
 			staking::internal::check_new_era();

substrate/polkadot/runtime/src/runtime/session.rs

@@ -217,46 +217,46 @@ mod tests {
 		let mut t = simple_setup();
 		with_externalities(&mut t, || {
 			// Block 1: Change to length 3; no visible change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			set_length(3);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 0);
 
 			// Block 2: Length now changed to 3. Index incremented.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			set_length(3);
 			check_rotate_session();
 			assert_eq!(length(), 3);
 			assert_eq!(current_index(), 1);
 
 			// Block 3: Length now changed to 3. Index incremented.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			check_rotate_session();
 			assert_eq!(length(), 3);
 			assert_eq!(current_index(), 1);
 
 			// Block 4: Change to length 2; no visible change.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			set_length(2);
 			check_rotate_session();
 			assert_eq!(length(), 3);
 			assert_eq!(current_index(), 1);
 
 			// Block 5: Length now changed to 2. Index incremented.
-			with_env(|e| e.block_number = 5);
+			system::testing::set_block_number(5);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 2);
 
 			// Block 6: No change.
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 2);
 
 			// Block 7: Next index.
-			with_env(|e| e.block_number = 7);
+			system::testing::set_block_number(7);
 			check_rotate_session();
 			assert_eq!(length(), 2);
 			assert_eq!(current_index(), 3);
@@ -268,17 +268,17 @@ mod tests {
 		let mut t = simple_setup();
 		with_externalities(&mut t, || {
 			// Block 1: No change
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 2: Session rollover, but no change.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 3: Set new key for validator 2; no visible change.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			set_key(&[20; 32], &[22; 32]);
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
@@ -286,7 +286,7 @@ mod tests {
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 4: Session rollover, authority 2 changes.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [22u8; 32]]);
 		});

substrate/polkadot/runtime/src/runtime/staking.rs

@@ -310,7 +310,7 @@ mod tests {
 			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
 
 			// Block 1: Add three validators. No obvious change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			stake(&one);
 			stake(&two);
 			stake(&four);
@@ -318,39 +318,39 @@ mod tests {
 			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
 
 			// Block 2: New validator set now.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			check_new_era();
 			assert_eq!(session::validators(), vec![four.clone(), two.clone()]);
 
 			// Block 3: Unstake highest, introduce another staker. No change yet.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			stake(&three);
 			unstake(&four);
 			check_new_era();
 
 			// Block 4: New era - validators change.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			check_new_era();
 			assert_eq!(session::validators(), vec![three.clone(), two.clone()]);
 
 			// Block 5: Transfer stake from highest to lowest. No change yet.
-			with_env(|e| e.block_number = 5);
+			system::testing::set_block_number(5);
 			transfer(&four, &one, 40);
 			check_new_era();
 
 			// Block 6: Lowest now validator.
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			check_new_era();
 			assert_eq!(session::validators(), vec![one.clone(), three.clone()]);
 
 			// Block 7: Unstake three. No change yet.
-			with_env(|e| e.block_number = 7);
+			system::testing::set_block_number(7);
 			unstake(&three);
 			check_new_era();
 			assert_eq!(session::validators(), vec![one.clone(), three.clone()]);
 
 			// Block 8: Back to one and two.
-			with_env(|e| e.block_number = 8);
+			system::testing::set_block_number(8);
 			check_new_era();
 			assert_eq!(session::validators(), vec![one.clone(), two.clone()]);
 		});
@@ -369,21 +369,21 @@ mod tests {
 			assert_eq!(current_era(), 0u64);
 
 			// Block 1: No change.
-			with_env(|e| e.block_number = 1);
+			system::testing::set_block_number(1);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 2u64);
 			assert_eq!(last_era_length_change(), 0u64);
 			assert_eq!(current_era(), 0u64);
 
 			// Block 2: Simple era change.
-			with_env(|e| e.block_number = 2);
+			system::testing::set_block_number(2);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 2u64);
 			assert_eq!(last_era_length_change(), 0u64);
 			assert_eq!(current_era(), 1u64);
 
 			// Block 3: Schedule an era length change; no visible changes.
-			with_env(|e| e.block_number = 3);
+			system::testing::set_block_number(3);
 			set_sessions_per_era(3);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 2u64);
@@ -391,28 +391,28 @@ mod tests {
 			assert_eq!(current_era(), 1u64);
 
 			// Block 4: Era change kicks in.
-			with_env(|e| e.block_number = 4);
+			system::testing::set_block_number(4);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 3u64);
 			assert_eq!(last_era_length_change(), 4u64);
 			assert_eq!(current_era(), 2u64);
 
 			// Block 5: No change.
-			with_env(|e| e.block_number = 5);
+			system::testing::set_block_number(5);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 3u64);
 			assert_eq!(last_era_length_change(), 4u64);
 			assert_eq!(current_era(), 2u64);
 
 			// Block 6: No change.
-			with_env(|e| e.block_number = 6);
+			system::testing::set_block_number(6);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 3u64);
 			assert_eq!(last_era_length_change(), 4u64);
 			assert_eq!(current_era(), 2u64);
 
 			// Block 7: Era increment.
-			with_env(|e| e.block_number = 7);
+			system::testing::set_block_number(7);
 			check_new_era();
 			assert_eq!(sessions_per_era(), 3u64);
 			assert_eq!(last_era_length_change(), 4u64);

substrate/polkadot/runtime/src/runtime/system.rs

@@ -264,6 +264,15 @@ fn info_expect_equal_hash(given: &Hash, expected: &Hash) {
 	}
 }
 
+#[cfg(any(feature = "std", test))]
+pub mod testing {
+	use super::*;
+
+	pub fn set_block_number(n: BlockNumber) {
+		with_env(|e| e.block_number = n);
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;