Extract the Engine trait (#10958)

* Add client-traits crate
Move the BlockInfo trait to new crate

* New crate `machine`
Contains code extracted from ethcore that defines `Machine`, `Externalities` and other execution related code.

* Use new machine and client-traits crates in ethcore

* Use new crates machine and client-traits instead of ethcore where appropriate

* Fix tests

* Don't re-export so many types from ethcore::client

* Fixing more fallout from removing re-export

* fix test

* More fallout from not re-exporting types

* Add some docs

* cleanup

* import the macro edition style

* Tweak docs

* Add missing import

* remove unused ethabi_derive imports

* Use latest ethabi-contract

* Move many traits from ethcore/client/traits to client-traits crate
Initial version of extracted Engine trait

* Move snapshot related traits to the engine crate (eew)

* Move a few snapshot related types to common_types
Cleanup Executed as exported from machine crate

* fix warning

* Gradually introduce new engine crate: snapshot

* ethcore typechecks with new engine crate

* Sort out types outside ethcore

* Add an EpochVerifier to ethash and use that in Engine.epoch_verifier()
Cleanup

* Document pub members

* Sort out tests
Sort out default impls for EpochVerifier

* Add test-helpers feature and move EngineSigner impl to the right place

* Sort out tests

* Sort out tests and refactor verification types

* Fix missing traits

* More missing traits
Fix Histogram

* Fix tests and cleanup

* cleanup

* Put back needed logger import

* Don't rexport common_types from ethcore/src/client
Don't export ethcore::client::*

* Remove files no longer used
Use types from the engine crate
Explicit exports from engine::engine

* Get rid of itertools

* Move a few more traits from ethcore to client-traits: BlockChainReset, ScheduleInfo, StateClient

* Move ProvingBlockChainClient to client-traits

* Don't re-export ForkChoice and Transition from ethcore

* Address grumbles: sort imports, remove commented out code

* Fix merge resolution error

* merge failure

ethcore/machine/src/executed.rs

@@ -16,58 +16,14 @@
 
 //! Transaction execution format module.
 
-use ethereum_types::{U256, Address};
-use parity_bytes::Bytes;
-use vm;
 use trace::{VMTrace, FlatTrace};
 use common_types::{
-	state_diff::StateDiff,
-	log_entry::LogEntry,
+	engines::machine,
 	errors::ExecutionError,
 };
 
-/// Transaction execution receipt.
-#[derive(Debug, PartialEq, Clone)]
-pub struct Executed<T = FlatTrace, V = VMTrace> {
-	/// True if the outer call/create resulted in an exceptional exit.
-	pub exception: Option<vm::Error>,
-
-	/// Gas paid up front for execution of transaction.
-	pub gas: U256,
-
-	/// Gas used during execution of transaction.
-	pub gas_used: U256,
-
-	/// Gas refunded after the execution of transaction.
-	/// To get gas that was required up front, add `refunded` and `gas_used`.
-	pub refunded: U256,
-
-	/// Cumulative gas used in current block so far.
-	///
-	/// `cumulative_gas_used = gas_used(t0) + gas_used(t1) + ... gas_used(tn)`
-	///
-	/// where `tn` is current transaction.
-	pub cumulative_gas_used: U256,
-
-	/// Vector of logs generated by transaction.
-	pub logs: Vec<LogEntry>,
-
-	/// Addresses of contracts created during execution of transaction.
-	/// Ordered from earliest creation.
-	///
-	/// eg. sender creates contract A and A in constructor creates contract B
-	///
-	/// B creation ends first, and it will be the first element of the vector.
-	pub contracts_created: Vec<Address>,
-	/// Transaction output.
-	pub output: Bytes,
-	/// The trace of this transaction.
-	pub trace: Vec<T>,
-	/// The VM trace of this transaction.
-	pub vm_trace: Option<V>,
-	/// The state diff, if we traced it.
-	pub state_diff: Option<StateDiff>,
-}
+/// /// Transaction execution receipt, parametrised with convenient defaults.
+pub type Executed = machine::Executed<FlatTrace, VMTrace>;
 
 /// Transaction execution result.
 pub type ExecutionResult = Result<Box<Executed>, ExecutionError>;

ethcore/machine/src/executive.rs

@@ -36,14 +36,14 @@ use trace::{self, Tracer, VMTracer};
 use common_types::{
 	errors::ExecutionError,
 	transaction::{Action, SignedTransaction},
+	engines::machine::Executed,
 };
 
 use crate::{
 	Machine,
 	substate::Substate,
-	externalities::{Externalities, OutputPolicy, OriginInfo}, // todo: make explicit
+	externalities::{Externalities, OutputPolicy, OriginInfo},
 	transaction_ext::Transaction,
-	executed::Executed,
 };
 
 #[cfg(debug_assertions)]

ethcore/machine/src/test_helpers.rs

@@ -20,7 +20,6 @@ use common_types::engines::params::CommonParams;
 use ethjson;
 use crate::Machine;
 
-
 pub fn load_machine(reader: &[u8]) -> Machine {
 	let spec = ethjson::spec::Spec::load(reader).expect("chain spec is invalid");
 

ethcore/machine/src/tx_filter.rs

@@ -153,12 +153,13 @@ mod test {
 	use tempdir::TempDir;
 	use ethereum_types::{U256, Address};
 
+	use client_traits::BlockChainClient;
 	use common_types::{
 		ids::BlockId,
 		transaction::{Transaction, Action}
 	};
 	use ethcore::{
-		client::{BlockChainClient, Client, ClientConfig},
+		client::{Client, ClientConfig},
 		spec::Spec,
 		miner::Miner,
 		test_helpers,