2019: fix new clippy lints

aoc2019/src/day03.rs

@@ -190,7 +190,7 @@ impl FromStr for Move {
     fn from_str(s: &str) -> Result<Self> {
         let direction = s
             .chars()
-            .nth(0)
+            .next()
             .context("couldn't get direction char in move")?;
 
         let s = s.get(1..).context("move missing length")?;

aoc2019/src/day04.rs

@@ -1,3 +1,4 @@
+use std::cmp::Ordering;
 use std::fmt::Write;
 
 use anyhow::{Context, Result};
@@ -59,17 +60,21 @@ fn part2(begin: usize, end: usize) -> Result<usize> {
         let mut count = 1;
         let mut prev = digits[0];
         for digit in digits.iter().skip(1) {
-            if prev > *digit {
+            match prev.cmp(digit) {
+                Ordering::Greater => {
                     ordered = false;
                     break;
-            } else if prev == *digit {
+                }
+                Ordering::Equal => {
                     count += 1;
-            } else {
+                }
+                Ordering::Less => {
                     if count == 2 {
                         pair = true;
                     }
                     count = 1;
                 }
+            }
 
             prev = *digit;
         }

aoc2019/src/day12.rs

@@ -1,3 +1,4 @@
+use std::cmp::Ordering;
 use std::fmt::Write;
 use std::str::FromStr;
 
@@ -52,29 +53,41 @@ fn part1(mut planets: Vec<Planet>, steps: usize) -> Result<u64> {
             let first = &mut begin[pair.0];
             let second = &mut end[0];
 
-            if first.position.x > second.position.x {
+            match first.position.x.cmp(&second.position.x) {
+                Ordering::Greater => {
                     first.velocity.x -= 1;
                     second.velocity.x += 1;
-            } else if first.position.x < second.position.x {
+                }
+                Ordering::Less => {
                     first.velocity.x += 1;
                     second.velocity.x -= 1;
                 }
+                Ordering::Equal => {}
+            }
 
-            if first.position.y > second.position.y {
+            match first.position.y.cmp(&second.position.y) {
+                Ordering::Greater => {
                     first.velocity.y -= 1;
                     second.velocity.y += 1;
-            } else if first.position.y < second.position.y {
+                }
+                Ordering::Less => {
                     first.velocity.y += 1;
                     second.velocity.y -= 1;
                 }
+                Ordering::Equal => {}
+            }
 
-            if first.position.z > second.position.z {
+            match first.position.z.cmp(&second.position.z) {
+                Ordering::Greater => {
                     first.velocity.z -= 1;
                     second.velocity.z += 1;
-            } else if first.position.z < second.position.z {
+                }
+                Ordering::Less => {
                     first.velocity.z += 1;
                     second.velocity.z -= 1;
                 }
+                Ordering::Equal => {}
+            }
         }
 
         // update position
@@ -114,29 +127,41 @@ fn part2(mut planets: Vec<Planet>) -> Result<usize> {
             let first = &mut begin[pair.0];
             let second = &mut end[0];
 
-            if first.position.x > second.position.x {
+            match first.position.x.cmp(&second.position.x) {
+                Ordering::Greater => {
                     first.velocity.x -= 1;
                     second.velocity.x += 1;
-            } else if first.position.x < second.position.x {
+                }
+                Ordering::Less => {
                     first.velocity.x += 1;
                     second.velocity.x -= 1;
                 }
+                Ordering::Equal => {}
+            }
 
-            if first.position.y > second.position.y {
+            match first.position.y.cmp(&second.position.y) {
+                Ordering::Greater => {
                     first.velocity.y -= 1;
                     second.velocity.y += 1;
-            } else if first.position.y < second.position.y {
+                }
+                Ordering::Less => {
                     first.velocity.y += 1;
                     second.velocity.y -= 1;
                 }
+                Ordering::Equal => {}
+            }
 
-            if first.position.z > second.position.z {
+            match first.position.z.cmp(&second.position.z) {
+                Ordering::Greater => {
                     first.velocity.z -= 1;
                     second.velocity.z += 1;
-            } else if first.position.z < second.position.z {
+                }
+                Ordering::Less => {
                     first.velocity.z += 1;
                     second.velocity.z -= 1;
                 }
+                Ordering::Equal => {}
+            }
         }
 
         // update position

aoc2019/src/day13.rs

@@ -1,3 +1,4 @@
+use std::cmp::Ordering;
 use std::collections::HashMap;
 use std::fmt::{self, Display, Write};
 
@@ -30,13 +31,7 @@ fn part1(memory: Vec<i64>) -> Result<usize> {
         map.insert(pos, tile);
     }
 
-    Ok(map
-        .values()
-        .filter(|t| match t {
-            Tile::Block => true,
-            _ => false,
-        })
-        .count())
+    Ok(map.values().filter(|t| matches!(t, Tile::Block)).count())
 }
 
 #[allow(dead_code)]
@@ -50,12 +45,10 @@ fn print_screen(screen: &[Vec<Tile>]) {
 }
 
 fn get_next_move(paddle_pos: (i64, i64), ball_pos: (i64, i64)) -> i64 {
-    if ball_pos.0 > paddle_pos.0 {
-        1
-    } else if ball_pos.0 == paddle_pos.0 {
-        0
-    } else {
-        -1
+    match ball_pos.0.cmp(&paddle_pos.0) {
+        Ordering::Greater => 1,
+        Ordering::Equal => 0,
+        Ordering::Less => -1,
     }
 }
 

aoc2019/src/day14.rs

@@ -90,7 +90,7 @@ fn get_ore_cost(
         in_stock += num_reactions * recipe.produced;
     }
 
-    inventory.insert(material.clone(), in_stock - quantity);
+    inventory.insert(material, in_stock - quantity);
 
     Ok(total)
 }