a few more tests for the accumulator

substrate/candidate-agreement/src/bft/accumulator.rs

@@ -524,4 +524,42 @@ mod tests {
 			s => panic!("wrong state: {:?}", s),
 		}
 	}
+
+	#[test]
+	fn begin_to_advance() {
+		let mut accumulator = Accumulator::<Candidate, Digest, _, _>::new(1, 3, ValidatorId(8));
+		assert_eq!(accumulator.state(), &State::Begin);
+
+		for i in 0..7 {
+			accumulator.import_message(LocalizedMessage {
+				sender: ValidatorId(i),
+				signature: Signature(1, i),
+				message: Message::AdvanceRound(1),
+			});
+		}
+
+		match accumulator.state() {
+			&State::Advanced(ref j) => assert!(j.is_none()),
+			s => panic!("wrong state: {:?}", s),
+		}
+	}
+
+	#[test]
+	fn conclude_without_prepare() {
+		let mut accumulator = Accumulator::<Candidate, _, _, _>::new(1, 3, ValidatorId(8));
+		assert_eq!(accumulator.state(), &State::Begin);
+
+		for i in 0..7 {
+			accumulator.import_message(LocalizedMessage {
+				sender: ValidatorId(i),
+				signature: Signature(999, i),
+				message: Message::Commit(1, Digest(999)),
+			});
+		}
+
+		match accumulator.state() {
+			&State::Concluded(ref j) => assert_eq!(j.digest, Digest(999)),
+			s => panic!("wrong state: {:?}", s),
+		}
+	}
 }

substrate/candidate-agreement/src/bft/mod.rs

@@ -67,7 +67,6 @@ pub struct Agreed<T, P, V, S> {
 pub struct Params<
 	Validator,
 	SignLocal,
-	Timeout,
 	CanInclude,
 	MessagesIn,
 	MessagesOut,
@@ -78,8 +77,6 @@ pub struct Params<
 	pub local_id: Validator,
 	/// A closure for signing local messages.
 	pub sign_local: SignLocal,
-	/// A timeout that fires when the view change should begin.
-	pub begin_view_change: Timeout,
 	/// A function for checking if a proposal can be voted for.
 	pub can_include: CanInclude,
 	/// The input stream. Should never conclude, and should yield only messages