Test sessions.

substrate/wasm-runtime/polkadot/src/runtime/session.rs

@@ -40,27 +40,20 @@ pub fn length() -> BlockNumber {
 	Storable::lookup_default(b"ses\0bps")
 }
 
-/// Hook to be called prior to transaction processing.
-pub fn pre_transactions() {
-	staking::pre_transactions();
-}
-
-/// Hook to be called after to transaction processing.
-pub fn post_transactions() {
-	staking::post_transactions();
-
+/// Hook to be called after transaction processing.
+pub fn check_rotate_session() {
 	// do this last, after the staking system has had chance to switch out the authorities for the
 	// new set.
 	// check block number and call next_session if necessary.
 	if system::block_number() % length() == 0 {
-		next_session();
+		rotate_session();
 	}
 }
 
-// PRIVATE (not available)
+// PRIVATE (not available for use externally)
 
 /// Move onto next session: register the new authority set.
-fn next_session() {
+fn rotate_session() {
 	validators().iter().enumerate().for_each(|(i, v)| {
 		let k = v.to_keyed_vec(b"ses\0nxt\0");
 		if let Some(n) = Storable::lookup(&k) {
@@ -70,4 +63,56 @@ fn next_session() {
 	});
 }
 
-// TODO: tests
+#[cfg(test)]
+mod tests {
+	use runtime_support::with_externalities;
+	use keyedvec::KeyedVec;
+	use joiner::Joiner;
+	use testing::{one, two, TestExternalities};
+	use primitives::AccountID;
+	use runtime::{consensus, session};
+	use environment::with_env;
+
+	#[test]
+	fn session_change_should_work() {
+		let mut t = TestExternalities { storage: map![
+			b"ses\0bps".to_vec() => vec![].join(&2u64),
+			// the validators (10, 20, ...)
+			b"ses\0key\0len".to_vec() => vec![].join(&2u32),
+			0u32.to_keyed_vec(b"ses\0key\0") => vec![10; 32],
+			1u32.to_keyed_vec(b"ses\0key\0") => vec![20; 32],
+			// initial session keys (11, 21, ...)
+			b"con\0aut\0len".to_vec() => vec![].join(&2u32),
+			0u32.to_keyed_vec(b"con\0aut\0") => vec![11; 32],
+			1u32.to_keyed_vec(b"con\0aut\0") => vec![21; 32]
+		], };
+		with_externalities(&mut t, || {
+			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
+			assert_eq!(session::length(), 2u64);
+			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
+
+			// Block 1: No change
+			with_env(|e| e.block_number = 1);
+			session::check_rotate_session();
+			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
+
+			// Block 2: Session rollover, but no change.
+			with_env(|e| e.block_number = 2);
+			session::check_rotate_session();
+			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
+
+			// Block 3: Set new key for validator 2; no visible change.
+			with_env(|e| e.block_number = 3);
+			session::set_key(&[20; 32], &[22; 32]);
+			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
+
+			session::check_rotate_session();
+			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
+
+			// Block 4: Session rollover, authority 2 changes.
+			with_env(|e| e.block_number = 4);
+			session::check_rotate_session();
+			assert_eq!(consensus::authorities(), vec![[11u8; 32], [22u8; 32]]);
+		});
+	}
+}