diff --git a/substrate/Cargo.lock b/substrate/Cargo.lock
index 83553ea5c3..0425fa82d4 100644
--- a/substrate/Cargo.lock
+++ b/substrate/Cargo.lock
@@ -1,3 +1,5 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
 [[package]]
 name = "MacTypes-sys"
 version = "2.1.0"
@@ -3420,7 +3422,7 @@ dependencies = [
  "once_cell 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-codec 3.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "paste 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "pretty_assertions 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pretty_assertions 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.90 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.90 (registry+https://github.com/rust-lang/crates.io-index)",
  "sr-io 1.0.0",
diff --git a/substrate/core/peerset/Cargo.toml b/substrate/core/peerset/Cargo.toml
index 1b505682d8..21d6bff69f 100644
--- a/substrate/core/peerset/Cargo.toml
+++ b/substrate/core/peerset/Cargo.toml
@@ -13,4 +13,4 @@ libp2p = { version = "0.6.0", default-features = false }
 linked-hash-map = "0.5"
 log = "0.4"
 lru-cache = "0.1.2"
-serde_json = "1.0.24"
+serde_json = "1.0.24"
\ No newline at end of file
diff --git a/substrate/core/peerset/src/slots.rs b/substrate/core/peerset/src/slots.rs
index 2ea9e5199b..4c6d9fab6c 100644
--- a/substrate/core/peerset/src/slots.rs
+++ b/substrate/core/peerset/src/slots.rs
@@ -161,14 +161,14 @@ impl Slots {
 
 	/// Marks given peer as a reserved one.
 	pub fn mark_reserved(&mut self, peer_id: &PeerId) {
-		if let Some(_) = self.common.remove(peer_id) {
+		if self.common.remove(peer_id).is_some() {
 			self.reserved.insert(peer_id.clone(), ());
 		}
 	}
 
 	/// Marks given peer as not reserved one.
 	pub fn mark_not_reserved(&mut self, peer_id: &PeerId) {
-		if let Some(_) = self.reserved.remove(peer_id) {
+		if self.reserved.remove(peer_id).is_some() {
 			self.common.insert(peer_id.clone(), ());
 		}
 	}
@@ -183,41 +183,3 @@ impl Slots {
 		self.reserved.contains_key(peer_id)
 	}
 }
-
-#[cfg(test)]
-mod tests {
-	use libp2p::PeerId;
-	use super::{Slots, SlotType};
-
-	#[test]
-	fn test_slots_debug() {
-		let reserved_peer = PeerId::random();
-		let reserved_peer2 = PeerId::random();
-		let common_peer = PeerId::random();
-		let mut slots = Slots::new(10);
-
-		slots.add_peer(reserved_peer.clone(), SlotType::Reserved);
-		slots.add_peer(reserved_peer2.clone(), SlotType::Reserved);
-		slots.add_peer(common_peer.clone(), SlotType::Common);
-
-		let expected = format!("Slots {{
-    max_slots: 10,
-    reserved: [
-        PeerId(
-            {:?}
-        ),
-        PeerId(
-            {:?}
-        )
-    ],
-    common: [
-        PeerId(
-            {:?}
-        )
-    ]
-}}", reserved_peer.to_base58(), reserved_peer2.to_base58(), common_peer.to_base58());
-
-		let s = format!("{:#?}", slots);
-		assert_eq!(expected, s);
-	}
-}
diff --git a/substrate/srml/support/Cargo.toml b/substrate/srml/support/Cargo.toml
index a126160d67..06fc3633ff 100644
--- a/substrate/srml/support/Cargo.toml
+++ b/substrate/srml/support/Cargo.toml
@@ -20,7 +20,7 @@ once_cell = { version = "0.1.6", default-features = false, optional = true }
 bitmask = { version = "0.5", default-features = false }
 
 [dev-dependencies]
-pretty_assertions = "0.5.1"
+pretty_assertions = "0.6.1"
 
 [features]
 default = ["std"]