From 45f8b6e91ff6c54260d25fcef84d17395764f8f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bastian=20K=C3=B6cher?= <bkchr@users.noreply.github.com>
Date: Sun, 13 Jun 2021 12:41:13 +0100
Subject: [PATCH] pallet-authorship: Fixing some nitpicks (#9095)

As reviewing the pallet yesterday, I have found some nitpicks that I
fixed.
---
 substrate/frame/authorship/src/lib.rs | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/substrate/frame/authorship/src/lib.rs b/substrate/frame/authorship/src/lib.rs
index 9b46a3fe11..98d20ec621 100644
--- a/substrate/frame/authorship/src/lib.rs
+++ b/substrate/frame/authorship/src/lib.rs
@@ -27,7 +27,7 @@ use frame_support::{
 	inherent::{InherentData, ProvideInherent, InherentIdentifier},
 };
 use codec::{Encode, Decode};
-use sp_runtime::traits::{Header as HeaderT, One, Zero};
+use sp_runtime::traits::{Header as HeaderT, One, Saturating};
 use sp_authorship::{INHERENT_IDENTIFIER, UnclesInherentData, InherentError};
 
 const MAX_UNCLES: usize = 10;
@@ -298,11 +298,7 @@ impl<T: Config> Pallet<T> {
 
 		let (minimum_height, maximum_height) = {
 			let uncle_generations = T::UncleGenerations::get();
-			let min = if now >= uncle_generations {
-				now - uncle_generations
-			} else {
-				Zero::zero()
-			};
+			let min = now.saturating_sub(uncle_generations);
 
 			(min, now)
 		};
@@ -329,7 +325,7 @@ impl<T: Config> Pallet<T> {
 			return Err(Error::<T>::OldUncle.into());
 		}
 
-		let duplicate = existing_uncles.into_iter().find(|h| **h == hash).is_some();
+		let duplicate = existing_uncles.into_iter().any(|h| *h == hash);
 		let in_chain = <frame_system::Pallet<T>>::block_hash(uncle.number()) == hash;
 
 		if duplicate || in_chain {
@@ -341,15 +337,14 @@ impl<T: Config> Pallet<T> {
 	}
 
 	fn prune_old_uncles(minimum_height: T::BlockNumber) {
-		let mut uncles = <Uncles<T>>::get();
+		let uncles = <Uncles<T>>::get();
 		let prune_entries = uncles.iter().take_while(|item| match item {
 			UncleEntryItem::Uncle(_, _) => true,
 			UncleEntryItem::InclusionHeight(height) => height < &minimum_height,
 		});
 		let prune_index = prune_entries.count();
 
-		let _ = uncles.drain(..prune_index);
-		<Uncles<T>>::put(uncles);
+		<Uncles<T>>::put(&uncles[prune_index..]);
 	}
 }