Add a few small snapshot tests (#2038)

* add manifest data test

* begin tests for io

* add unit tests for snapshot io

* service smoke test

* remove empty service module

ethcore/src/snapshot/tests/helpers.rs

@@ -78,7 +78,7 @@ impl StateProducer {
 		let new_accs = rng.gen::<u32>() % 5;
 
 		for _ in 0..new_accs {
-			let address_hash = H256::random();
+			let address_hash = H256(rng.gen());
 			let balance: usize = rng.gen();
 			let nonce: usize = rng.gen();
 			let acc = ::state::Account::new_basic(balance.into(), nonce.into()).rlp();

ethcore/src/snapshot/tests/mod.rs

@@ -19,4 +19,19 @@
 mod blocks;
 mod state;
 
-pub mod helpers;
+pub mod helpers;
+
+use super::ManifestData;
+
+#[test]
+fn manifest_rlp() {
+	let manifest = ManifestData {
+		block_hashes: Vec::new(),
+		state_hashes: Vec::new(),
+		block_number: 1234567,
+		state_root: Default::default(),
+		block_hash: Default::default(),
+	};
+	let raw = manifest.clone().into_rlp();
+	assert_eq!(ManifestData::from_rlp(&raw).unwrap(), manifest);
+}

ethcore/src/snapshot/tests/state.rs

@@ -20,7 +20,7 @@ use snapshot::{chunk_state, Progress, StateRebuilder};
 use snapshot::io::{PackedReader, PackedWriter, SnapshotReader, SnapshotWriter};
 use super::helpers::{compare_dbs, StateProducer};
 
-use rand;
+use rand::{XorShiftRng, SeedableRng};
 use util::hash::H256;
 use util::journaldb::{self, Algorithm};
 use util::kvdb::{Database, DatabaseConfig};
@@ -33,7 +33,7 @@ use std::sync::Arc;
 #[test]
 fn snap_and_restore() {
 	let mut producer = StateProducer::new();
-	let mut rng = rand::thread_rng();
+	let mut rng = XorShiftRng::from_seed([1, 2, 3, 4]);
 	let mut old_db = MemoryDB::new();
 	let db_cfg = DatabaseConfig::with_columns(::db::NUM_COLUMNS);