Extract engines to own crates (#10966)

* 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

* Extract the Clique engine to own crate

* Extract NullEngine and the block_reward module from ethcore

* Extract InstantSeal engine to own crate

* Extract remaining engines

* Extract executive_state to own crate so it can be used by engine crates

* Remove snapshot stuff from the engine crate

* Put snapshot traits back in ethcore

* cleanup

* Remove stuff from ethcore

* Don't use itertools

* itertools in aura is legit-ish

* More post-merge fixes

* Re-export less types in client

* cleanup

* Update ethcore/block-reward/Cargo.toml

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update ethcore/engines/basic-authority/Cargo.toml

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update ethcore/engines/ethash/Cargo.toml

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update ethcore/engines/clique/src/lib.rs

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* signers is already a ref

* Add an EngineType enum to tighten up Engine.name()

* Introduce Snapshotting enum to distinguish the type of snapshots a chain uses

* Rename supports_warp to snapshot_mode

* Missing import

* Update ethcore/src/snapshot/consensus/mod.rs

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* remove double-semicolons

ethcore/src/client/client.rs

@@ -20,6 +20,7 @@ use std::sync::atomic::{AtomicUsize, AtomicBool, Ordering as AtomicOrdering};
 use std::sync::{Arc, Weak};
 use std::time::{Instant, Duration};
 
+use account_state::state::StateInfo;
 use blockchain::{BlockReceipts, BlockChain, BlockChainDB, BlockProvider, TreeRoute, ImportRoute, TransactionAddress, ExtrasInsert, BlockNumberKey};
 use bytes::Bytes;
 use call_contract::{CallContract, RegistryInfo};
@@ -39,7 +40,7 @@ use hash_db::EMPTY_PREFIX;
 use block::{LockedBlock, Drain, ClosedBlock, OpenBlock, enact_verified, SealedBlock};
 use client::ancient_import::AncientVerifier;
 use client::{
-	ReopenBlock, PrepareOpenBlock, ImportSealedBlock, BroadcastProposalBlock, StateInfo,
+	ReopenBlock, PrepareOpenBlock, ImportSealedBlock, BroadcastProposalBlock,
 	Call, BlockProducer, SealedBlockImporter, ChainNotify, EngineInfo,
 	ClientConfig, NewBlocks, ChainRoute, ChainMessageType, bad_blocks, ClientIoMessage,
 };
@@ -85,7 +86,7 @@ use types::{
 	log_entry::LocalizedLogEntry,
 	receipt::{Receipt, LocalizedReceipt},
 	header::Header,
-	snapshot::Progress,
+	snapshot::{Progress, Snapshotting},
 	trace_filter::Filter as TraceFilter,
 	pruning_info::PruningInfo,
 	call_analytics::CallAnalytics,
@@ -1020,7 +1021,7 @@ impl Client {
 	}
 
 	/// Get shared miner reference.
-	#[cfg(test)]
+	#[cfg(any(test, feature = "test-helpers"))]
 	pub fn miner(&self) -> Arc<Miner> {
 		self.importer.miner.clone()
 	}
@@ -1168,6 +1169,9 @@ impl Client {
 		at: BlockId,
 		p: &Progress,
 	) -> Result<(), EthcoreError> {
+		if let Snapshotting::Unsupported = self.engine.snapshot_mode() {
+			return Err(EthcoreError::Snapshot(SnapshotError::SnapshotsUnsupported));
+		}
 		let db = self.state_db.read().journal_db().boxed_clone();
 		let best_block_number = self.chain_info().best_block_number;
 		let block_number = self.block_number(at).ok_or_else(|| SnapshotError::InvalidStartingBlock(at))?;
@@ -1197,7 +1201,7 @@ impl Client {
 		};
 
 		let processing_threads = self.config.snapshot.processing_threads;
-		let chunker = self.engine.snapshot_components().ok_or_else(|| SnapshotError::SnapshotsUnsupported)?;
+		let chunker = snapshot::chunker(self.engine.snapshot_mode()).ok_or_else(|| SnapshotError::SnapshotsUnsupported)?;
 		snapshot::take_snapshot(
 			chunker,
 			&self.chain.read(),
@@ -1227,10 +1231,8 @@ impl Client {
 	fn transaction_address(&self, id: TransactionId) -> Option<TransactionAddress> {
 		match id {
 			TransactionId::Hash(ref hash) => self.chain.read().transaction_address(hash),
-			TransactionId::Location(id, index) => Self::block_hash(&self.chain.read(), id).map(|hash| TransactionAddress {
-				block_hash: hash,
-				index: index,
-			})
+			TransactionId::Location(id, index) => Self::block_hash(&self.chain.read(), id).map(|block_hash|
+				TransactionAddress { block_hash, index })
 		}
 	}
 

ethcore/src/client/evm_test_client.rs

@@ -21,7 +21,7 @@ use std::sync::Arc;
 use ethereum_types::{H256, U256, H160};
 use {trie_vm_factories, journaldb, trie, kvdb_memorydb};
 use kvdb::{self, KeyValueDB};
-use {state_db, client, trace, db, spec};
+use {state_db, trace, db, spec};
 use pod::PodState;
 use types::{
 	errors::EthcoreError,
@@ -214,7 +214,7 @@ impl<'a> EvmTestClient<'a> {
 	) -> Result<FinalizationResult, EvmTestError>
 	{
 		let genesis = self.spec.genesis_header();
-		let info = client::EnvInfo {
+		let info = vm::EnvInfo {
 			number: genesis.number(),
 			author: *genesis.author(),
 			timestamp: genesis.timestamp(),
@@ -233,7 +233,7 @@ impl<'a> EvmTestClient<'a> {
 		params: ActionParams,
 		tracer: &mut T,
 		vm_tracer: &mut V,
-		info: client::EnvInfo,
+		info: vm::EnvInfo,
 	) -> Result<FinalizationResult, EvmTestError>
 	{
 		let mut substate = Substate::new();
@@ -252,7 +252,7 @@ impl<'a> EvmTestClient<'a> {
 	/// Returns the state root, gas left and the output.
 	pub fn transact<T: trace::Tracer, V: trace::VMTracer>(
 		&mut self,
-		env_info: &client::EnvInfo,
+		env_info: &vm::EnvInfo,
 		transaction: transaction::SignedTransaction,
 		tracer: T,
 		vm_tracer: V,

ethcore/src/client/io_message.rs

@@ -18,7 +18,7 @@ use std::fmt;
 use bytes::Bytes;
 use client::Client;
 use ethereum_types::H256;
-use snapshot::ManifestData;
+use types::snapshot::ManifestData;
 
 /// Message type for external and internal events
 #[derive(Debug)]

ethcore/src/client/mod.rs

@@ -38,13 +38,8 @@ pub use self::traits::{
     ReopenBlock, PrepareOpenBlock, ImportSealedBlock, BroadcastProposalBlock,
     Call, EngineInfo, BlockProducer, SealedBlockImporter,
 };
-pub use account_state::state::StateInfo;
-
-
-pub use vm::{LastHashes, EnvInfo};
 
 pub use verification::VerifierType;
 
 mod traits;
-
 mod chain_notify;

ethcore/src/client/test_client.rs

@@ -59,14 +59,13 @@ use types::{
 	blockchain_info::BlockChainInfo,
 	block_status::BlockStatus,
 };
-use vm::Schedule;
+use vm::{Schedule, LastHashes};
 
 use block::{OpenBlock, SealedBlock, ClosedBlock};
 use call_contract::{CallContract, RegistryInfo};
 use client::{
 	ReopenBlock, PrepareOpenBlock, ImportSealedBlock, BroadcastProposalBlock, Call,
 	EngineInfo, BlockProducer, SealedBlockImporter,
-	LastHashes,
 };
 use client_traits::{
 	BlockInfo, Nonce, Balance, ChainInfo, TransactionInfo, BlockChainClient, ImportBlock,