State Machine: Abstract function execution (#19)

* initial primitives

* add block primitives

* state machine: backend

* in-memory backend

* tests for overlayed storage

* blanked impl for state machine error

* abstract call execution

* squash warnings temporarily

* fix contracts crate

* address grumbles

* remove redundant state-machine dependency

substrate/contracts/src/auth.rs

@@ -15,7 +15,7 @@
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
 
 use primitives::Address;
-use state_machine::Externalities;
+use state_machine::StaticExternalities;
 
 use error::Result;
 use executor::RustExecutor;
@@ -32,7 +32,7 @@ impl Contract {
 	/// Given Message and Authentication Data verifies it and returns:
 	/// 1. None in case it doesn't match (i.e. signature is invalid)
 	/// 2. A address who signed that Message.
-	pub fn check_auth<E: Externalities<RustExecutor>>(&self, _ext: &E, _data: DataAndAuth) -> Result<Option<Address>> {
+	pub fn check_auth<E: StaticExternalities<RustExecutor>>(&self, _ext: &E, _data: DataAndAuth) -> Result<Option<Address>> {
 		unimplemented!()
 	}
 }

substrate/contracts/src/balances.rs

@@ -16,7 +16,7 @@
 
 use primitives::Address;
 use primitives::uint::U256;
-use state_machine::Externalities;
+use state_machine::{Externalities, StaticExternalities};
 
 use error::Result;
 use executor::RustExecutor;
@@ -38,12 +38,12 @@ pub struct Transfer {
 pub struct Contract;
 impl Contract {
 	/// Returns a balance of given address.
-	pub fn balance_of<E: Externalities<RustExecutor>>(&self, _ext: &E, _data: Address) -> Result<U256> {
+	pub fn balance_of<E: StaticExternalities<RustExecutor>>(&self, _ext: &E, _data: Address) -> Result<U256> {
 		unimplemented!()
 	}
 
 	/// Returns the next nonce to authorize the transfer from given address.
-	pub fn next_nonce<E: Externalities<RustExecutor>>(&self, _ext: &E, _data: Address) -> Result<U256> {
+	pub fn next_nonce<E: StaticExternalities<RustExecutor>>(&self, _ext: &E, _data: Address) -> Result<U256> {
 		unimplemented!()
 	}
 
@@ -52,7 +52,7 @@ impl Contract {
 	/// - signature
 	/// - replay protection
 	/// - enough balance
-	pub fn transfer_preconditions<E: Externalities<RustExecutor>>(&self, _db: &E, _data: Transfer) -> Result<bool> {
+	pub fn transfer_preconditions<E: StaticExternalities<RustExecutor>>(&self, _db: &E, _data: Transfer) -> Result<bool> {
 		unimplemented!()
 	}
 

substrate/contracts/src/error.rs

@@ -46,5 +46,3 @@ error_chain! {
 		}
 	}
 }
-
-impl state_machine::Error for Error {}

substrate/contracts/src/executor.rs

@@ -18,7 +18,7 @@
 
 use primitives::contract::{CallData, OutData};
 use serializer::{from_slice as de, to_vec as ser};
-use state_machine::{Externalities, Executor};
+use state_machine::{StaticExternalities, Externalities, Executor};
 
 use error::{Error, ErrorKind, Result};
 use auth;
@@ -45,7 +45,7 @@ impl RustExecutor {
 impl Executor for RustExecutor {
 	type Error = Error;
 
-	fn static_call<E: Externalities<Self>>(
+	fn call_static<E: StaticExternalities<Self>>(
 		&self,
 		ext: &E,
 		code: &[u8],
@@ -95,11 +95,31 @@ impl Executor for RustExecutor {
 #[cfg(test)]
 mod tests {
 	use super::*;
+	use primitives::Address;
+	use primitives::hash::H256;
 
 	#[derive(Debug, Default)]
 	struct TestExternalities;
 	impl Externalities<RustExecutor> for TestExternalities {
+		fn set_storage(&mut self, _key: H256, _value: Vec<u8>) {
+			unimplemented!()
+		}
+
+		fn call(&mut self, _address: &Address, _method: &str, _data: &CallData) -> Result<OutData> {
+			unimplemented!()
+		}
+	}
+
+	impl StaticExternalities<RustExecutor> for TestExternalities {
 		type Error = Error;
+
+		fn storage(&self, _key: &H256) -> Result<&[u8]> {
+			unimplemented!()
+		}
+
+		fn call_static(&self, _address: &Address, _method: &str, _data: &CallData) -> Result<OutData> {
+			unimplemented!()
+		}
 	}
 
 	#[test]

substrate/contracts/src/validator_set.rs

@@ -15,7 +15,7 @@
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
 
 use primitives::Address;
-use state_machine::Externalities;
+use state_machine::StaticExternalities;
 
 use error::Result;
 use executor::RustExecutor;
@@ -25,7 +25,7 @@ use executor::RustExecutor;
 pub struct Contract;
 impl Contract {
 	/// Returns current validator set.
-	pub fn validator_set<E: Externalities<RustExecutor>>(&self, _db: &E, _data: ()) -> Result<Vec<Address>> {
+	pub fn validator_set<E: StaticExternalities<RustExecutor>>(&self, _db: &E, _data: ()) -> Result<Vec<Address>> {
 		unimplemented!()
 	}
 }