simplify kvdb error types (#8924)

ethcore/src/blockchain/blockchain.rs

@@ -17,8 +17,9 @@
 //! Blockchain database.
 
 use std::collections::{HashMap, HashSet};
+use std::path::Path;
 use std::sync::Arc;
-use std::mem;
+use std::{mem, io};
 use itertools::Itertools;
 use blooms_db;
 use heapsize::HeapSizeOf;
@@ -47,8 +48,6 @@ use engines::epoch::{Transition as EpochTransition, PendingTransition as Pending
 use rayon::prelude::*;
 use ansi_term::Colour;
 use kvdb::{DBTransaction, KeyValueDB};
-use error::Error;
-use std::path::Path;
 
 /// Database backing `BlockChain`.
 pub trait BlockChainDB: Send + Sync {
@@ -66,7 +65,7 @@ pub trait BlockChainDB: Send + Sync {
 /// predefined config.
 pub trait BlockChainDBHandler: Send + Sync {
 	/// Open the predefined key-value database.
-	fn open(&self, path: &Path) -> Result<Arc<BlockChainDB>, Error>;
+	fn open(&self, path: &Path) -> io::Result<Arc<BlockChainDB>>;
 }
 
 /// Interface for querying blocks by hash and by number.

ethcore/src/client/client.rs

@@ -718,7 +718,7 @@ impl Client {
 			state_db = spec.ensure_db_good(state_db, &factories)?;
 			let mut batch = DBTransaction::new();
 			state_db.journal_under(&mut batch, 0, &spec.genesis_header().hash())?;
-			db.key_value().write(batch).map_err(ClientError::Database)?;
+			db.key_value().write(batch)?;
 		}
 
 		let gb = spec.genesis_block();
@@ -821,7 +821,7 @@ impl Client {
 		}
 
 		// ensure buffered changes are flushed.
-		client.db.read().key_value().flush().map_err(ClientError::Database)?;
+		client.db.read().key_value().flush()?;
 		Ok(client)
 	}
 

ethcore/src/client/error.rs

@@ -16,7 +16,6 @@
 
 use std::fmt::{Display, Formatter, Error as FmtError};
 use util_error::UtilError;
-use kvdb;
 use trie::TrieError;
 
 /// Client configuration errors.
@@ -24,8 +23,6 @@ use trie::TrieError;
 pub enum Error {
 	/// TrieDB-related error.
 	Trie(TrieError),
-	/// Database error
-	Database(kvdb::Error),
 	/// Util error
 	Util(UtilError),
 }
@@ -53,7 +50,6 @@ impl Display for Error {
 		match *self {
 			Error::Trie(ref err) => write!(f, "{}", err),
 			Error::Util(ref err) => write!(f, "{}", err),
-			Error::Database(ref s) => write!(f, "Database error: {}", s),
 		}
 	}
 }

ethcore/src/client/evm_test_client.rs

@@ -35,8 +35,6 @@ pub enum EvmTestError {
 	Evm(vm::Error),
 	/// Initialization error.
 	ClientError(::error::Error),
-	/// Low-level database error.
-	Database(kvdb::Error),
 	/// Post-condition failure,
 	PostCondition(String),
 }
@@ -55,7 +53,6 @@ impl fmt::Display for EvmTestError {
 			Trie(ref err) => write!(fmt, "Trie: {}", err),
 			Evm(ref err) => write!(fmt, "EVM: {}", err),
 			ClientError(ref err) => write!(fmt, "{}", err),
-			Database(ref err) => write!(fmt, "DB: {}", err),
 			PostCondition(ref err) => write!(fmt, "{}", err),
 		}
 	}
@@ -135,7 +132,7 @@ impl<'a> EvmTestClient<'a> {
 		{
 			let mut batch = kvdb::DBTransaction::new();
 			state_db.journal_under(&mut batch, 0, &genesis.hash())?;
-			db.write(batch).map_err(EvmTestError::Database)?;
+			db.write(batch)?;
 		}
 
 		state::State::from_existing(

ethcore/src/error.rs

@@ -18,7 +18,6 @@
 
 use std::{fmt, error};
 use std::time::SystemTime;
-use kvdb;
 use ethereum_types::{H256, U256, Address, Bloom};
 use util_error::{self, UtilError};
 use snappy::InvalidInput;
@@ -237,11 +236,10 @@ error_chain! {
 	}
 
 	links {
-		Database(kvdb::Error, kvdb::ErrorKind) #[doc = "Database error."];
 		Util(UtilError, util_error::ErrorKind) #[doc = "Error concerning a utility"];
 		Import(ImportError, ImportErrorKind) #[doc = "Error concerning block import." ];
 	}
-		
+
 	foreign_links {
 		Io(IoError) #[doc = "Io create error"];
 		StdIo(::std::io::Error) #[doc = "Error concerning the Rust standard library's IO subsystem."];
@@ -271,14 +269,14 @@ error_chain! {
 		AccountProvider(err: AccountsError) {
 			description("Accounts Provider error")
 			display("Accounts Provider error {}", err)
-		} 
+		}
 
 		#[doc = "PoW hash is invalid or out of date."]
 		PowHashInvalid {
 			description("PoW hash is invalid or out of date.")
 			display("PoW hash is invalid or out of date.")
 		}
-	
+
 		#[doc = "The value of the nonce or mishash is invalid."]
 		PowInvalid {
 			description("The value of the nonce or mishash is invalid.")
@@ -311,10 +309,10 @@ impl From<ClientError> for Error {
 	}
 }
 
-impl From<AccountsError> for Error { 
-	fn from(err: AccountsError) -> Error { 
+impl From<AccountsError> for Error {
+	fn from(err: AccountsError) -> Error {
 		ErrorKind::AccountProvider(err).into()
-	} 
+	}
 }
 
 impl From<::rlp::DecoderError> for Error {

ethcore/src/test_helpers.rs

@@ -17,7 +17,8 @@
 //! Set of different helpers for client tests
 
 use std::path::Path;
-use std::fs;
+use std::sync::Arc;
+use std::{fs, io};
 use account_provider::AccountProvider;
 use ethereum_types::{H256, U256, Address};
 use block::{OpenBlock, Drain};
@@ -25,7 +26,6 @@ use blockchain::{BlockChain, BlockChainDB, BlockChainDBHandler, Config as BlockC
 use bytes::Bytes;
 use client::{Client, ClientConfig, ChainInfo, ImportBlock, ChainNotify, ChainMessageType, PrepareOpenBlock};
 use ethkey::KeyPair;
-use error::Error;
 use evm::Factory as EvmFactory;
 use factory::Factories;
 use hash::keccak;
@@ -37,7 +37,6 @@ use rlp::{self, RlpStream};
 use spec::Spec;
 use state_db::StateDB;
 use state::*;
-use std::sync::Arc;
 use transaction::{Action, Transaction, SignedTransaction};
 use views::BlockView;
 use blooms_db;
@@ -327,7 +326,7 @@ pub fn restoration_db_handler(config: kvdb_rocksdb::DatabaseConfig) -> Box<Block
 	}
 
 	impl BlockChainDBHandler for RestorationDBHandler {
-		fn open(&self, db_path: &Path) -> Result<Arc<BlockChainDB>, Error> {
+		fn open(&self, db_path: &Path) -> io::Result<Arc<BlockChainDB>> {
 			let key_value = Arc::new(kvdb_rocksdb::Database::open(&self.config, &db_path.to_string_lossy())?);
 			let blooms_path = db_path.join("blooms");
 			let trace_blooms_path = db_path.join("trace_blooms");