fix(ManageNetwork): replace Range with RangeInclusive (#10209)

* fix(ManageNetwork): replace Range -> RangeIncls

Fixes `TODO: Range should be changed to RangeInclusive once stable (https://github.com/rust-lang/rust/pull/50758)`

* fix(tests)

* fix(grumbles): off-by-one error in debug_asserts

* RangeInclusive::end() is inclusive which means that if start and end is equal the `debug_assert(range.end() >
range.start()` will fail which is shouldn't

ethcore/sync/src/api.rs

@@ -17,7 +17,7 @@
 use std::sync::{Arc, mpsc, atomic};
 use std::collections::{HashMap, BTreeMap};
 use std::io;
-use std::ops::Range;
+use std::ops::RangeInclusive;
 use std::time::Duration;
 use bytes::Bytes;
 use devp2p::NetworkService;
@@ -615,9 +615,7 @@ pub trait ManageNetwork : Send + Sync {
 	/// Stop network
 	fn stop_network(&self);
 	/// Returns the minimum and maximum peers.
-	/// Note that `range.end` is *exclusive*.
-	// TODO: Range should be changed to RangeInclusive once stable (https://github.com/rust-lang/rust/pull/50758)
-	fn num_peers_range(&self) -> Range<u32>;
+	fn num_peers_range(&self) -> RangeInclusive<u32>;
 	/// Get network context for protocol.
 	fn with_proto_context(&self, proto: ProtocolId, f: &mut FnMut(&NetworkContext));
 }
@@ -656,7 +654,7 @@ impl ManageNetwork for EthSync {
 		self.stop();
 	}
 
-	fn num_peers_range(&self) -> Range<u32> {
+	fn num_peers_range(&self) -> RangeInclusive<u32> {
 		self.network.num_peers_range()
 	}
 
@@ -935,7 +933,7 @@ impl ManageNetwork for LightSync {
 		self.network.stop();
 	}
 
-	fn num_peers_range(&self) -> Range<u32> {
+	fn num_peers_range(&self) -> RangeInclusive<u32> {
 		self.network.num_peers_range()
 	}
 
@@ -948,12 +946,12 @@ impl LightSyncProvider for LightSync {
 	fn peer_numbers(&self) -> PeerNumbers {
 		let (connected, active) = self.proto.peer_count();
 		let peers_range = self.num_peers_range();
-		debug_assert!(peers_range.end > peers_range.start);
+		debug_assert!(peers_range.end() >= peers_range.start());
 		PeerNumbers {
 			connected: connected,
 			active: active,
-			max: peers_range.end as usize - 1,
-			min: peers_range.start as usize,
+			max: *peers_range.end() as usize,
+			min: *peers_range.start() as usize,
 		}
 	}
 

parity/informant.rs

@@ -146,7 +146,7 @@ impl InformantData for FullNodeInformantData {
 			(Some(sync), Some(net)) => {
 				let status = sync.status();
 				let num_peers_range = net.num_peers_range();
-				debug_assert!(num_peers_range.end > num_peers_range.start);
+				debug_assert!(num_peers_range.end() >= num_peers_range.start());
 
 				cache_sizes.insert("sync", status.mem_used);
 
@@ -154,7 +154,7 @@ impl InformantData for FullNodeInformantData {
 					last_imported_block_number: status.last_imported_block_number.unwrap_or(chain_info.best_block_number),
 					last_imported_old_block_number: status.last_imported_old_block_number,
 					num_peers: status.num_peers,
-					max_peers: status.current_max_peers(num_peers_range.start, num_peers_range.end - 1),
+					max_peers: status.current_max_peers(*num_peers_range.start(), *num_peers_range.end()),
 					snapshot_sync: status.is_snapshot_syncing(),
 				})
 			}

rpc/src/v1/impls/parity.rs

@@ -187,13 +187,13 @@ impl<C, M, U, S> Parity for ParityClient<C, M, U> where
 	fn net_peers(&self) -> Result<Peers> {
 		let sync_status = self.sync.status();
 		let num_peers_range = self.net.num_peers_range();
-		debug_assert!(num_peers_range.end > num_peers_range.start);
+		debug_assert!(num_peers_range.end() >= num_peers_range.start());
 		let peers = self.sync.peers().into_iter().map(Into::into).collect();
 
 		Ok(Peers {
 			active: sync_status.num_active_peers,
 			connected: sync_status.num_peers,
-			max: sync_status.current_max_peers(num_peers_range.start, num_peers_range.end - 1),
+			max: sync_status.current_max_peers(*num_peers_range.start(), *num_peers_range.end()),
 			peers: peers
 		})
 	}

rpc/src/v1/tests/mocked/manage_network.rs

@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity Ethereum.  If not, see <http://www.gnu.org/licenses/>.
 
-use std::ops::Range;
+use std::ops::RangeInclusive;
 use sync::ManageNetwork;
 use self::ethcore_network::{ProtocolId, NetworkContext};
 
@@ -30,6 +30,6 @@ impl ManageNetwork for TestManageNetwork {
 	fn add_reserved_peer(&self, _peer: String) -> Result<(), String> { Ok(()) }
 	fn start_network(&self) {}
 	fn stop_network(&self) {}
-	fn num_peers_range(&self) -> Range<u32> { 25 .. 51 }
+	fn num_peers_range(&self) -> RangeInclusive<u32> { 25..=50 }
 	fn with_proto_context(&self, _: ProtocolId, _: &mut FnMut(&NetworkContext)) { }
 }

util/network-devp2p/src/service.rs

@@ -20,7 +20,7 @@ use host::Host;
 use io::*;
 use parking_lot::RwLock;
 use std::net::SocketAddr;
-use std::ops::Range;
+use std::ops::RangeInclusive;
 use std::sync::Arc;
 use ansi_term::Colour;
 use network::ConnectionFilter;
@@ -95,12 +95,8 @@ impl NetworkService {
 	}
 
 	/// Returns the number of peers allowed.
-	///
-	/// Keep in mind that `range.end` is *exclusive*.
-	pub fn num_peers_range(&self) -> Range<u32> {
-		let start = self.config.min_peers;
-		let end = self.config.max_peers + 1;
-		start .. end
+	pub fn num_peers_range(&self) -> RangeInclusive<u32> {
+		self.config.min_peers..=self.config.max_peers
 	}
 
 	/// Returns external url if available.