test previous code fetch

Former-commit-id: 0c5f895a0f2a7f073d8f3998fe81648305a53665

ethcore/src/snapshot/account.rs

@@ -225,7 +225,7 @@ mod tests {
 	use util::{Address, FixedHash, H256, HashDB, DBValue};
 	use rlp::{UntrustedRlp, View};
 
-	use std::collections::{HashSet, HashMap};
+	use std::collections::HashSet;
 
 	use super::{ACC_EMPTY, Account};
 

ethcore/src/snapshot/tests/state.rs

@@ -17,6 +17,7 @@
 //! State snapshotting tests.
 
 use snapshot::{chunk_state, Progress, StateRebuilder};
+use snapshot::account::Account;
 use snapshot::io::{PackedReader, PackedWriter, SnapshotReader, SnapshotWriter};
 use super::helpers::{compare_dbs, StateProducer};
 
@@ -28,6 +29,8 @@ use util::memorydb::MemoryDB;
 use util::Mutex;
 use devtools::RandomTempPath;
 
+use util::sha3::SHA3_NULL_RLP;
+
 use std::sync::Arc;
 
 #[test]
@@ -82,3 +85,54 @@ fn snap_and_restore() {
 
 	compare_dbs(&old_db, new_db.as_hashdb());
 }
+
+#[test]
+fn get_code_from_prev_chunk() {
+	use std::collections::HashSet;
+	use rlp::{RlpStream, Stream};
+	use util::{HashDB, H256, FixedHash, U256, Hashable};
+
+	use account_db::{AccountDBMut, AccountDB};
+
+	let code = b"this is definitely code";
+	let mut used_code = HashSet::new();
+	let mut acc_stream = RlpStream::new_list(4);
+	acc_stream.append(&U256::default())
+		.append(&U256::default())
+		.append(&SHA3_NULL_RLP)
+		.append(&code.sha3());
+
+	let (h1, h2) = (H256::random(), H256::random());
+
+	// two accounts with the same code, one per chunk.
+	// first one will have code inlined,
+	// second will just have its hash.
+	let thin_rlp = acc_stream.out();
+	let acc1 = Account::from_thin_rlp(&thin_rlp);
+	let acc2 = Account::from_thin_rlp(&thin_rlp);
+
+	let mut make_chunk = |acc: Account, hash| {
+		let mut db = MemoryDB::new();
+		AccountDBMut::from_hash(&mut db, hash).insert(&code[..]);
+
+		let fat_rlp = acc.to_fat_rlp(&AccountDB::from_hash(&db, hash), &mut used_code).unwrap();
+
+		let mut stream = RlpStream::new_list(1);
+		stream.begin_list(2).append(&hash).append_raw(&fat_rlp, 1);
+		stream.out()
+	};
+
+	let chunk1 = make_chunk(acc1, h1);
+	let chunk2 = make_chunk(acc2, h2);
+
+	let db_path = RandomTempPath::create_dir();
+	let db_cfg = DatabaseConfig::with_columns(::db::NUM_COLUMNS);
+	let new_db = Arc::new(Database::open(&db_cfg, &db_path.to_string_lossy()).unwrap());
+
+	let mut rebuilder = StateRebuilder::new(new_db, Algorithm::Archive);
+
+	rebuilder.feed(&chunk1).unwrap();
+	rebuilder.feed(&chunk2).unwrap();
+
+	rebuilder.check_missing().unwrap();
+}