diff --git a/ethcore/src/blockchain/extras.rs b/ethcore/src/blockchain/extras.rs
index 9e1109f1a..0e6dadbfe 100644
--- a/ethcore/src/blockchain/extras.rs
+++ b/ethcore/src/blockchain/extras.rs
@@ -242,3 +242,21 @@ impl HeapSizeOf for BlockReceipts {
 		self.receipts.heap_size_of_children()
 	}
 }
+
+#[cfg(test)]
+mod tests {
+	use rlp::*;
+	use super::BlockReceipts;
+
+	#[test]
+	fn encode_block_receipts() {
+		let br = BlockReceipts::new(Vec::new());
+
+		let mut s = RlpStream::new_list(2);
+		s.append(&br);
+		assert!(!s.is_finished(), "List shouldn't finished yet");
+		s.append(&br);
+		assert!(s.is_finished(), "List should be finished now");
+		s.out();
+	}
+}
diff --git a/ethcore/src/engines/tendermint/message.rs b/ethcore/src/engines/tendermint/message.rs
index 8d7bffdfa..2cddd9e69 100644
--- a/ethcore/src/engines/tendermint/message.rs
+++ b/ethcore/src/engines/tendermint/message.rs
@@ -215,6 +215,18 @@ mod tests {
 	use super::super::Step;
 	use super::*;
 
+	#[test]
+	fn encode_step() {
+		let step = Step::Precommit;
+
+		let mut s = RlpStream::new_list(2);
+		s.append(&step);
+		assert!(!s.is_finished(), "List shouldn't finished yet");
+		s.append(&step);
+		assert!(s.is_finished(), "List should be finished now");
+		s.out();
+	}
+
 	#[test]
 	fn encode_decode() {
 		let message = ConsensusMessage {
diff --git a/ethcore/src/types/executed.rs b/ethcore/src/types/executed.rs
index b8a9cb970..21858c194 100644
--- a/ethcore/src/types/executed.rs
+++ b/ethcore/src/types/executed.rs
@@ -212,12 +212,28 @@ impl fmt::Display for CallError {
 /// Transaction execution result.
 pub type ExecutionResult = Result<Executed, ExecutionError>;
 
-#[test]
-fn should_encode_and_decode_call_type() {
-	use rlp;
+#[cfg(test)]
+mod tests {
+	use rlp::*;
+	use super::CallType;
 
-	let original = CallType::Call;
-	let encoded = rlp::encode(&original);
-	let decoded = rlp::decode(&encoded);
-	assert_eq!(original, decoded);
+	#[test]
+	fn encode_call_type() {
+		let ct = CallType::Call;
+
+		let mut s = RlpStream::new_list(2);
+		s.append(&ct);
+		assert!(!s.is_finished(), "List shouldn't finished yet");
+		s.append(&ct);
+		assert!(s.is_finished(), "List should be finished now");
+		s.out();
+	}
+
+	#[test]
+	fn should_encode_and_decode_call_type() {
+		let original = CallType::Call;
+		let encoded = encode(&original);
+		let decoded = decode(&encoded);
+		assert_eq!(original, decoded);
+	}
 }
diff --git a/ethcore/src/types/trace_types/error.rs b/ethcore/src/types/trace_types/error.rs
index 9a2f29f3b..7eb16570c 100644
--- a/ethcore/src/types/trace_types/error.rs
+++ b/ethcore/src/types/trace_types/error.rs
@@ -98,3 +98,21 @@ impl Decodable for Error {
 		}
 	}
 }
+
+#[cfg(test)]
+mod tests {
+	use rlp::*;
+	use super::Error;
+
+	#[test]
+	fn encode_error() {
+		let err = Error::BadJumpDestination;
+
+		let mut s = RlpStream::new_list(2);
+		s.append(&err);
+		assert!(!s.is_finished(), "List shouldn't finished yet");
+		s.append(&err);
+		assert!(s.is_finished(), "List should be finished now");
+		s.out();
+	}
+}
diff --git a/ethcore/src/types/trace_types/flat.rs b/ethcore/src/types/trace_types/flat.rs
index 6ceff86d9..870f13802 100644
--- a/ethcore/src/types/trace_types/flat.rs
+++ b/ethcore/src/types/trace_types/flat.rs
@@ -162,10 +162,35 @@ impl Into<Vec<FlatTransactionTraces>> for FlatBlockTraces {
 
 #[cfg(test)]
 mod tests {
+	use rlp::*;
 	use super::{FlatBlockTraces, FlatTransactionTraces, FlatTrace};
 	use trace::trace::{Action, Res, CallResult, Call, Suicide};
 	use types::executed::CallType;
 
+	#[test]
+	fn encode_flat_transaction_traces() {
+		let ftt = FlatTransactionTraces::from(Vec::new());
+
+		let mut s = RlpStream::new_list(2);
+		s.append(&ftt);
+		assert!(!s.is_finished(), "List shouldn't finished yet");
+		s.append(&ftt);
+		assert!(s.is_finished(), "List should be finished now");
+		s.out();
+	}
+
+	#[test]
+	fn encode_flat_block_traces() {
+		let fbt = FlatBlockTraces::from(Vec::new());
+
+		let mut s = RlpStream::new_list(2);
+		s.append(&fbt);
+		assert!(!s.is_finished(), "List shouldn't finished yet");
+		s.append(&fbt);
+		assert!(s.is_finished(), "List should be finished now");
+		s.out();
+	}
+
 	#[test]
 	fn test_trace_serialization() {
 		// block #51921