Expose commit in externalities.

Also refactor `TestExternalities` into a single place.

substrate/executor/src/native_executor.rs

@@ -41,8 +41,9 @@ impl CodeExecutor for NativeExecutor {
 #[cfg(test)]
 mod tests {
 	use super::*;
+	use runtime_std::TestExternalities;
 	use native_runtime::codec::KeyedVec;
-	use native_runtime::support::{TestExternalities, one, two, StaticHexInto};
+	use native_runtime::support::{one, two, StaticHexInto};
 	use native_runtime::runtime::staking::balance;
 	use primitives::twox_128;
 

substrate/executor/src/wasm_executor.rs

@@ -279,8 +279,8 @@ mod tests {
 	use super::*;
 	use rustc_hex::FromHex;
 	use primitives::{blake2_256, twox_128};
-	use runtime_std;
-	use native_runtime::support::{one, two, StaticHexInto, TestExternalities};
+	use runtime_std::{self, TestExternalities};
+	use native_runtime::support::{one, two, StaticHexInto};
 	use native_runtime::codec::KeyedVec;
 	use native_runtime::runtime::staking::balance;
 

substrate/native-runtime/std/src/lib.rs

@@ -39,7 +39,7 @@ pub mod prelude {
 	pub use std::boxed::Box;
 }
 
-pub use polkadot_state_machine::{Externalities, ExternalitiesError};
+pub use polkadot_state_machine::{Externalities, ExternalitiesError, TestExternalities};
 use primitives::hexdisplay::HexDisplay;
 
 // TODO: use the real error, not NoError.
@@ -92,6 +92,13 @@ pub fn chain_id() -> u64 {
 	).unwrap_or(0)
 }
 
+/// "Commit" all existing operations and get the resultant storage root.
+pub fn commit() -> [u8; 32] {
+	ext::with(|ext|
+		ext.commit()
+	).unwrap_or([0u8; 32])
+}
+
 /// Conduct a Keccak-256 hash of the given data.
 pub use primitives::{blake2_256, twox_128, twox_256};
 
@@ -140,23 +147,6 @@ macro_rules! impl_stubs {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use std::collections::HashMap;
-
-	#[derive(Debug, Default)]
-	struct TestExternalities {
-		storage: HashMap<Vec<u8>, Vec<u8>>,
-	}
-	impl Externalities for TestExternalities {
-		fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
-			Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
-		}
-
-		fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>) {
-			self.storage.insert(key, value);
-		}
-
-		fn chain_id(&self) -> u64 { 42 }
-	}
 
 	macro_rules! map {
 		($( $name:expr => $value:expr ),*) => (

substrate/state_machine/src/ext.rs

@@ -75,4 +75,8 @@ impl<'a, B: 'a> Externalities for Ext<'a, B>
 	fn chain_id(&self) -> u64 {
 		42
 	}
+
+	fn commit(&self) -> [u8; 32] {
+		unimplemented!();
+	}
 }

substrate/state_machine/src/lib.rs

@@ -35,6 +35,9 @@ use primitives::contract::{CallData};
 
 pub mod backend;
 mod ext;
+mod testing;
+
+pub use testing::TestExternalities;
 
 /// Updates to be committed to the state.
 pub enum Update {
@@ -141,6 +144,9 @@ pub trait Externalities {
 	/// Get the identity of the chain.
 	fn chain_id(&self) -> u64;
 
+	/// Get the trie root of the current storage map.
+	fn commit(&self) -> [u8; 32];
+
 	/// Get the current set of authorities from storage.
 	fn authorities(&self) -> Result<Vec<&[u8]>, ExternalitiesError> {
 		(0..self.storage(b"con:aut:len")?.into_iter()
@@ -210,8 +216,7 @@ pub fn execute<B: backend::Backend, Exec: CodeExecutor>(
 
 #[cfg(test)]
 mod tests {
-	use std::collections::HashMap;
-	use super::{OverlayedChanges, Externalities, ExternalitiesError};
+	use super::{OverlayedChanges, Externalities, TestExternalities};
 
 	#[test]
 	fn overlayed_storage_works() {
@@ -238,22 +243,6 @@ mod tests {
 		assert!(overlayed.storage(&key).is_none());
 	}
 
-	#[derive(Debug, Default)]
-	struct TestExternalities {
-		storage: HashMap<Vec<u8>, Vec<u8>>,
-	}
-	impl Externalities for TestExternalities {
-		fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
-			Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
-		}
-
-		fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>) {
-			self.storage.insert(key, value);
-		}
-
-		fn chain_id(&self) -> u64 { 42 }
-	}
-
 	#[test]
 	fn authorities_call_works() {
 		let mut ext = TestExternalities::default();

substrate/state_machine/src/testing.rs

@@ -0,0 +1,42 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Test implementation for Externalities.
+
+use std::collections::HashMap;
+use super::{Externalities, ExternalitiesError};
+
+/// Simple HashMap based Externalities impl.
+#[derive(Debug, Default)]
+pub struct TestExternalities {
+	pub storage: HashMap<Vec<u8>, Vec<u8>>,
+}
+
+impl Externalities for TestExternalities {
+	fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
+		Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
+	}
+
+	fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>) {
+		self.storage.insert(key, value);
+	}
+
+	fn chain_id(&self) -> u64 { 42 }
+
+	fn commit(&self) -> [u8; 32] {
+		unimplemented!();
+	}
+}

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

@@ -114,9 +114,9 @@ pub mod internal {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use runtime_std::{with_externalities, twox_128};
+	use runtime_std::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
-	use support::{one, two, TestExternalities, with_env};
+	use support::{one, two, with_env};
 	use primitives::{AccountID, InternalFunction};
 	use runtime::{staking, session};
 

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

@@ -132,9 +132,9 @@ mod tests {
 	use super::public::*;
 	use super::privileged::*;
 	use super::internal::*;
-	use runtime_std::{with_externalities, twox_128};
+	use runtime_std::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
-	use support::{one, two, TestExternalities, with_env};
+	use support::{one, two, with_env};
 	use primitives::AccountID;
 	use runtime::{consensus, session};
 

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

@@ -206,9 +206,9 @@ mod tests {
 	use super::public::*;
 	use super::privileged::*;
 
-	use runtime_std::{with_externalities, twox_128};
+	use runtime_std::{with_externalities, twox_128, TestExternalities};
 	use codec::{KeyedVec, Joiner};
-	use support::{one, two, TestExternalities, with_env};
+	use support::{one, two, with_env};
 	use primitives::AccountID;
 	use runtime::{staking, session};
 

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

@@ -127,9 +127,9 @@ mod tests {
 	use super::*;
 	use super::internal::*;
 
-	use runtime_std::{with_externalities, twox_128};
+	use runtime_std::{with_externalities, twox_128, TestExternalities};
 	use codec::{Joiner, KeyedVec, Slicable};
-	use support::{StaticHexInto, TestExternalities, HexDisplay, one, two};
+	use support::{StaticHexInto, HexDisplay, one, two};
 	use primitives::{UncheckedTransaction, Transaction, Function};
 	use runtime::staking;
 

substrate/wasm-runtime/polkadot/src/runtime/timestamp.rs

@@ -42,10 +42,9 @@ mod tests {
 	use super::*;
 	use super::public::*;
 
-	use runtime_std::{with_externalities, twox_128};
+	use runtime_std::{with_externalities, twox_128, TestExternalities};
 	use runtime::timestamp;
 	use codec::{Joiner, KeyedVec};
-	use support::TestExternalities;
 
 	#[test]
 	fn timestamp_works() {

substrate/wasm-runtime/polkadot/src/support/mod.rs

@@ -31,4 +31,4 @@ pub use self::hashable::Hashable;
 #[cfg(feature = "with-std")]
 pub use self::statichex::{StaticHexConversion, StaticHexInto};
 #[cfg(feature = "with-std")]
-pub use self::testing::{AsBytesRef, HexDisplay, TestExternalities, one, two};
+pub use self::testing::{AsBytesRef, HexDisplay, one, two};

substrate/wasm-runtime/polkadot/src/support/storage.rs

@@ -146,9 +146,8 @@ pub trait StorageVec {
 mod tests {
 	use super::*;
 	use std::collections::HashMap;
-	use runtime_std::with_externalities;
-	use support::{TestExternalities, HexDisplay};
-	use runtime_std::{storage, twox_128};
+	use support::HexDisplay;
+	use runtime_std::{storage, twox_128, TestExternalities, with_externalities};
 
 	#[test]
 	fn integers_can_be_stored() {

substrate/wasm-runtime/polkadot/src/support/testing.rs

@@ -16,30 +16,9 @@
 
 //! Testing helpers.
 
-use std::collections::HashMap;
-use runtime_std::{Externalities, ExternalitiesError};
 use primitives::AccountID;
 use super::statichex::StaticHexInto;
 
-#[derive(Debug, Default)]
-/// Simple externaties implementation.
-pub struct TestExternalities {
-	/// The storage map.
-	pub storage: HashMap<Vec<u8>, Vec<u8>>,
-}
-
-impl Externalities for TestExternalities {
-	fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
-		Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
-	}
-
-	fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>) {
-		self.storage.insert(key, value);
-	}
-
-	fn chain_id(&self) -> u64 { 42 }
-}
-
 #[macro_export]
 macro_rules! map {
 	($( $name:expr => $value:expr ),*) => (