reorg interpreter and adjust rustfmt (rust-ethereum#287)

reorg interpreter crate
 - extract exit module from error module
 - move trap module into error module
 - add machine module
 - move memory and stack modules into machine module
 
add more rustfmt configs

```toml
imports_granularity="Crate"
group_imports = "StdExternalCrate"
```

interpreter/src/error.rs → interpreter/src/error/exit.rs

@@ -1,32 +1,7 @@
-use crate::Opcode;
 use alloc::borrow::Cow;
 use core::fmt;
 
-/// Capture represents the result of execution.
-#[derive(Clone, Copy, Debug, Eq, PartialEq)]
-pub enum Capture<E, T> {
-	/// The machine has exited. It cannot be executed again.
-	Exit(E),
-	/// The machine has trapped. It is waiting for external information, and can
-	/// be executed again.
-	Trap(T),
-}
-
-impl<E, T> Capture<E, T> {
-	pub fn exit(self) -> Option<E> {
-		match self {
-			Self::Exit(e) => Some(e),
-			Self::Trap(_) => None,
-		}
-	}
-
-	pub fn trap(self) -> Option<T> {
-		match self {
-			Self::Exit(_) => None,
-			Self::Trap(t) => Some(t),
-		}
-	}
-}
+use crate::opcode::Opcode;
 
 /// Exit result.
 pub type ExitResult = Result<ExitSucceed, ExitError>;

interpreter/src/error/mod.rs

@@ -0,0 +1,30 @@
+mod exit;
+mod trap;
+
+pub use self::{exit::*, trap::*};
+
+/// Capture represents the result of execution.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum Capture<E, T> {
+	/// The machine has exited. It cannot be executed again.
+	Exit(E),
+	/// The machine has trapped. It is waiting for external information, and can
+	/// be executed again.
+	Trap(T),
+}
+
+impl<E, T> Capture<E, T> {
+	pub fn exit(self) -> Option<E> {
+		match self {
+			Self::Exit(e) => Some(e),
+			Self::Trap(_) => None,
+		}
+	}
+
+	pub fn trap(self) -> Option<T> {
+		match self {
+			Self::Exit(_) => None,
+			Self::Trap(t) => Some(t),
+		}
+	}
+}

interpreter/src/trap.rs → interpreter/src/error/trap.rs

@@ -1,16 +1,22 @@
 //! Call and create trap handler.
 
-use crate::utils::{h256_to_u256, u256_to_usize};
-use crate::{
-	interpreter::Interpreter, Context, ExitError, ExitException, ExitResult, Machine, Memory,
-	RuntimeBackend, RuntimeState, Transfer,
-};
 use alloc::vec::Vec;
-use core::cmp::{max, min};
-use core::convert::Infallible;
+use core::{
+	cmp::{max, min},
+	convert::Infallible,
+};
+
 use primitive_types::{H160, H256, U256};
 use sha3::{Digest, Keccak256};
 
+use crate::{
+	error::{ExitError, ExitException, ExitResult},
+	interpreter::Interpreter,
+	machine::{Machine, Memory},
+	runtime::{Context, RuntimeBackend, RuntimeState, Transfer},
+	utils::{h256_to_u256, u256_to_usize},
+};
+
 pub trait TrapConstruct<T> {
 	fn construct(v: T) -> Self;
 }
@@ -21,72 +27,6 @@ pub trait TrapConsume<T> {
 	fn consume(self) -> Result<T, Self::Rest>;
 }
 
-/// Create scheme.
-#[derive(Clone, Copy, Eq, PartialEq, Debug)]
-pub enum CreateScheme {
-	/// Legacy create scheme of `CREATE`.
-	Legacy {
-		/// Caller of the create.
-		caller: H160,
-	},
-	/// Create scheme of `CREATE2`.
-	Create2 {
-		/// Caller of the create.
-		caller: H160,
-		/// Code hash.
-		code_hash: H256,
-		/// Salt.
-		salt: H256,
-	},
-}
-
-impl CreateScheme {
-	pub fn address<H: RuntimeBackend>(&self, handler: &H) -> H160 {
-		match self {
-			Self::Create2 {
-				caller,
-				code_hash,
-				salt,
-			} => {
-				let mut hasher = Keccak256::new();
-				hasher.update([0xff]);
-				hasher.update(&caller[..]);
-				hasher.update(&salt[..]);
-				hasher.update(&code_hash[..]);
-				H256::from_slice(hasher.finalize().as_slice()).into()
-			}
-			Self::Legacy { caller } => {
-				let nonce = handler.nonce(*caller);
-				let mut stream = rlp::RlpStream::new_list(2);
-				stream.append(caller);
-				stream.append(&nonce);
-				H256::from_slice(Keccak256::digest(&stream.out()).as_slice()).into()
-			}
-		}
-	}
-
-	#[must_use]
-	pub const fn caller(&self) -> H160 {
-		match self {
-			Self::Create2 { caller, .. } => *caller,
-			Self::Legacy { caller } => *caller,
-		}
-	}
-}
-
-/// Call scheme.
-#[derive(Clone, Copy, Eq, PartialEq, Debug)]
-pub enum CallScheme {
-	/// `CALL`
-	Call,
-	/// `CALLCODE`
-	CallCode,
-	/// `DELEGATECALL`
-	DelegateCall,
-	/// `STATICCALL`
-	StaticCall,
-}
-
 pub enum CallCreateTrap {
 	Create,
 	Create2,
@@ -161,6 +101,20 @@ impl CallCreateTrapData {
 	}
 }
 
+/// Call scheme.
+#[derive(Clone, Copy, Eq, PartialEq, Debug)]
+pub enum CallScheme {
+	/// `CALL`
+	Call,
+	/// `CALLCODE`
+	CallCode,
+	/// `DELEGATECALL`
+	DelegateCall,
+	/// `STATICCALL`
+	StaticCall,
+}
+
+#[derive(Clone, Debug)]
 pub struct CallTrapData {
 	pub target: H160,
 	pub transfer: Option<Transfer>,
@@ -376,6 +330,59 @@ impl CallTrapData {
 	}
 }
 
+/// Create scheme.
+#[derive(Clone, Copy, Eq, PartialEq, Debug)]
+pub enum CreateScheme {
+	/// Legacy create scheme of `CREATE`.
+	Legacy {
+		/// Caller of the create call.
+		caller: H160,
+	},
+	/// Create scheme of `CREATE2`.
+	Create2 {
+		/// Caller of the create call.
+		caller: H160,
+		/// Code hash.
+		code_hash: H256,
+		/// Salt.
+		salt: H256,
+	},
+}
+
+impl CreateScheme {
+	pub fn address<H: RuntimeBackend>(&self, handler: &H) -> H160 {
+		match self {
+			Self::Create2 {
+				caller,
+				code_hash,
+				salt,
+			} => {
+				let mut hasher = Keccak256::new();
+				hasher.update([0xff]);
+				hasher.update(&caller[..]);
+				hasher.update(&salt[..]);
+				hasher.update(&code_hash[..]);
+				H256::from_slice(hasher.finalize().as_slice()).into()
+			}
+			Self::Legacy { caller } => {
+				let nonce = handler.nonce(*caller);
+				let mut stream = rlp::RlpStream::new_list(2);
+				stream.append(caller);
+				stream.append(&nonce);
+				H256::from_slice(Keccak256::digest(&stream.out()).as_slice()).into()
+			}
+		}
+	}
+
+	#[must_use]
+	pub const fn caller(&self) -> H160 {
+		match self {
+			Self::Create2 { caller, .. } => *caller,
+			Self::Legacy { caller } => *caller,
+		}
+	}
+}
+
 #[derive(Clone, Debug)]
 pub struct CreateTrapData {
 	pub scheme: CreateScheme,

interpreter/src/etable.rs

@@ -1,9 +1,15 @@
+use core::{
+	marker::PhantomData,
+	ops::{Deref, DerefMut},
+};
+
 use crate::{
-	eval::*, trap::CallCreateTrap, ExitResult, GasState, Machine, Opcode, RuntimeBackend,
-	RuntimeEnvironment, RuntimeState, TrapConstruct,
+	error::{CallCreateTrap, ExitResult, TrapConstruct},
+	eval::*,
+	machine::Machine,
+	opcode::Opcode,
+	runtime::{GasState, RuntimeBackend, RuntimeEnvironment, RuntimeState},
 };
-use core::marker::PhantomData;
-use core::ops::{Deref, DerefMut};
 
 pub trait EtableSet {
 	type State;

interpreter/src/eval/arithmetic.rs

@@ -1,8 +1,9 @@
-use crate::utils::I256;
-use core::convert::TryInto;
 use core::ops::Rem;
+
 use primitive_types::{U256, U512};
 
+use crate::utils::I256;
+
 #[inline]
 pub fn div(op1: U256, op2: U256) -> U256 {
 	if op2 == U256::zero() {

interpreter/src/eval/bitwise.rs

@@ -1,6 +1,7 @@
-use crate::utils::{Sign, I256};
 use primitive_types::U256;
 
+use crate::utils::{Sign, I256};
+
 #[inline]
 pub fn slt(op1: U256, op2: U256) -> U256 {
 	let op1: I256 = op1.into();

interpreter/src/eval/misc.rs

@@ -1,9 +1,14 @@
-use super::Control;
-use crate::utils::u256_to_h256;
-use crate::{ExitError, ExitException, ExitFatal, ExitSucceed, Machine};
 use core::cmp::min;
+
 use primitive_types::{H256, U256};
 
+use crate::{
+	error::{ExitError, ExitException, ExitFatal, ExitSucceed},
+	etable::Control,
+	machine::Machine,
+	utils::u256_to_h256,
+};
+
 #[inline]
 pub fn codesize<S, Tr>(state: &mut Machine<S>) -> Control<Tr> {
 	let stack = &mut state.stack;

interpreter/src/eval/mod.rs

@@ -5,13 +5,18 @@ mod bitwise;
 mod misc;
 mod system;
 
-use crate::{
-	trap::CallCreateTrap, Control, ExitException, ExitSucceed, GasState, Machine, Opcode,
-	RuntimeBackend, RuntimeEnvironment, RuntimeState, TrapConstruct,
-};
 use core::ops::{BitAnd, BitOr, BitXor};
+
 use primitive_types::{H256, U256};
 
+use crate::{
+	error::{CallCreateTrap, ExitException, ExitSucceed, TrapConstruct},
+	etable::Control,
+	machine::Machine,
+	opcode::Opcode,
+	runtime::{GasState, RuntimeBackend, RuntimeEnvironment, RuntimeState},
+};
+
 pub fn eval_pass<S, H, Tr>(
 	_machine: &mut Machine<S>,
 	_handle: &mut H,

interpreter/src/eval/system.rs

@@ -1,12 +1,15 @@
-use super::Control;
-use crate::{
-	ExitException, ExitFatal, ExitSucceed, GasState, Log, Machine, RuntimeBackend,
-	RuntimeEnvironment, RuntimeState, Transfer,
-};
 use alloc::vec::Vec;
+
 use primitive_types::{H256, U256};
 use sha3::{Digest, Keccak256};
 
+use crate::{
+	error::{ExitException, ExitFatal, ExitSucceed},
+	etable::Control,
+	machine::Machine,
+	runtime::{GasState, Log, RuntimeBackend, RuntimeEnvironment, RuntimeState, Transfer},
+};
+
 pub fn sha3<S: AsRef<RuntimeState>, Tr>(machine: &mut Machine<S>) -> Control<Tr> {
 	pop_u256!(machine, from, len);
 

interpreter/src/interpreter/etable.rs

@@ -1,11 +1,14 @@
-use crate::interpreter::{Interpreter, RunInterpreter, StepInterpreter};
-use crate::{
-	Capture, Control, EtableSet, ExitError, ExitException, ExitFatal, ExitResult, ExitSucceed,
-	Machine, Opcode, Stack, Valids,
-};
 use alloc::vec::Vec;
 use core::ops::{Deref, DerefMut};
 
+use crate::{
+	error::{Capture, ExitError, ExitException, ExitFatal, ExitResult, ExitSucceed},
+	etable::{Control, EtableSet},
+	interpreter::{valids::Valids, Interpreter, RunInterpreter, StepInterpreter},
+	machine::{Machine, Stack},
+	opcode::Opcode,
+};
+
 pub struct EtableInterpreter<'etable, ES: EtableSet> {
 	valids: Valids,
 	position: usize,

interpreter/src/interpreter/mod.rs

@@ -1,10 +1,14 @@
 mod etable;
+mod valids;
 
-pub use self::etable::EtableInterpreter;
-
-use crate::{Capture, ExitResult, Machine};
 use alloc::vec::Vec;
 
+pub use self::etable::EtableInterpreter;
+use crate::{
+	error::{Capture, ExitResult},
+	machine::Machine,
+};
+
 pub trait Interpreter {
 	type State;