2019: switch to anyhow

Cargo.lock

@@ -34,6 +34,7 @@ dependencies = [
 name = "aoc2019"
 version = "0.1.0"
 dependencies = [
+ "anyhow",
  "aoc",
  "criterion",
 ]

aoc2019/Cargo.toml

@@ -13,6 +13,7 @@ criterion = "0.3"
 [dependencies]
 
 aoc = { path = "../aoc" }
+anyhow = "1.0"
 
 [lib]
 path = "src/lib.rs"

aoc2019/src/day01.rs

@@ -1,6 +1,6 @@
 use std::fmt::Write;
 
-use aoc::Result;
+use anyhow::Result;
 
 const INPUT: &str = include_str!("../input/day01.txt");
 
@@ -21,10 +21,7 @@ fn part1(input: &str) -> Result<u64> {
     input
         .lines()
         .map(|line| line.parse::<u64>())
-        .map(|w| match w {
+        .map(|w| w.map(fuel_needed).map_err(anyhow::Error::new))
-            Ok(w) => Ok(fuel_needed(w)),
-            Err(e) => Err(Box::from(e)),
-        })
         .sum()
 }
 
@@ -44,10 +41,7 @@ fn part2(input: &str) -> Result<u64> {
     input
         .lines()
         .map(|line| line.parse::<u64>())
-        .map(|w| match w {
+        .map(|w| w.map(cumulated_fuel_needed).map_err(anyhow::Error::new))
-            Ok(w) => Ok(cumulated_fuel_needed(w)),
-            Err(e) => Err(Box::from(e)),
-        })
         .sum()
 }
 

aoc2019/src/day02.rs

@@ -1,7 +1,6 @@
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{anyhow, bail, Context, Result};
-use aoc::Result;
 
 use crate::intcode::{parse_memory, Intcode};
 
@@ -28,7 +27,7 @@ fn part1(mut input: Vec<i64>) -> Result<i64> {
 
     intcode
         .get_day02_output()
-        .ok_or_else(|| err!("intcode memory was empty!"))
+        .context("intcode memory was empty!")
 }
 
 fn part2(input: &[i64], res: i64) -> Result<i64> {
@@ -46,11 +45,11 @@ fn part2(input: &[i64], res: i64) -> Result<i64> {
                     return Ok(noun * 100 + verb);
                 }
             }
-            None => return Err(err!("intcode memory was empty!")),
+            None => bail!("intcode memory was empty!"),
         }
     }
 
-    Err(err!(
+    Err(anyhow!(
         "couldn't find noun/verb combination that produces {}",
         res
     ))

aoc2019/src/day03.rs

@@ -1,10 +1,8 @@
 use std::cmp::{max, min};
-use std::error::Error;
 use std::fmt::Write;
 use std::str::FromStr;
 
-use aoc::err;
+use anyhow::{bail, Context, Result};
-use aoc::Result;
 
 const INPUT: &str = include_str!("../input/day03.txt");
 
@@ -39,7 +37,7 @@ fn part1(first_wire: &Wire, second_wire: &Wire) -> Result<u64> {
         })
         .map(|inter| manhattan_distance(&inter, &Point { x: 0, y: 0 }))
         .min()
-        .ok_or_else(|| err!("wire was empty"))
+        .context("wire was empty")
 }
 
 fn part2(first_wire: &Wire, second_wire: &Wire) -> Result<u64> {
@@ -72,19 +70,13 @@ fn part2(first_wire: &Wire, second_wire: &Wire) -> Result<u64> {
         first_length += manhattan_distance(&seg1.begin, &seg1.end);
     }
 
-    min_dist.ok_or_else(|| err!("wire was empty"))
+    min_dist.context("wire was empty")
 }
 
 fn parse_wires(input: &str) -> Result<(Wire, Wire)> {
     let mut lines = input.lines();
-    let first = lines
+    let first = lines.next().context("input missing a line")?.parse()?;
-        .next()
+    let second = lines.next().context("input missing a line")?.parse()?;
-        .ok_or_else(|| err!("input missing a line"))?
-        .parse()?;
-    let second = lines
-        .next()
-        .ok_or_else(|| err!("input missing a line"))?
-        .parse()?;
 
     Ok((first, second))
 }
@@ -93,15 +85,14 @@ fn parse_wires(input: &str) -> Result<(Wire, Wire)> {
 struct Wire(Vec<Segment>);
 
 impl FromStr for Wire {
-    type Err = Box<dyn Error>;
+    type Err = anyhow::Error;
 
     fn from_str(s: &str) -> Result<Wire> {
         let moves = s
             .trim_end()
             .split(',')
-            .map(|m| m.parse())
+            .map(|m| m.parse().context("failed to parse wire"))
-            .collect::<Result<Vec<Move>>>()
+            .collect::<Result<Vec<Move>>>()?;
-            .map_err(|e| err!("failed to parse wire: {}", e))?;
 
         let mut pos = Point { x: 0, y: 0 };
 
@@ -194,17 +185,15 @@ struct Move {
 }
 
 impl FromStr for Move {
-    type Err = Box<dyn Error>;
+    type Err = anyhow::Error;
 
     fn from_str(s: &str) -> Result<Self> {
         let direction = s
             .chars()
             .nth(0)
-            .ok_or_else(|| err!("couldn't get direction char in move: {}", s))?;
+            .context("couldn't get direction char in move")?;
 
-        let s = s
+        let s = s.get(1..).context("move missing length")?;
-            .get(1..)
-            .ok_or_else(|| err!("move missing length: {}", s))?;
 
         let length = s.parse()?;
 
@@ -213,7 +202,7 @@ impl FromStr for Move {
             'D' => Direction::Down,
             'L' => Direction::Left,
             'R' => Direction::Right,
-            _ => return Err(err!("couldn't parse direction: {}", direction)),
+            _ => bail!("couldn't parse direction: {}", direction),
         };
 
         Ok(Move { direction, length })

aoc2019/src/day04.rs

@@ -1,7 +1,6 @@
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 const INPUT: &str = include_str!("../input/day04.txt");
 
@@ -20,11 +19,11 @@ fn range(input: &str) -> Result<(usize, usize)> {
     let mut range = input.trim_end().split('-');
     let begin = range
         .next()
-        .ok_or_else(|| err!("invalid input: {}", input))?
+        .with_context(|| format!("invalid input: {}", input))?
         .parse()?;
     let end = range
         .next()
-        .ok_or_else(|| err!("invalid input: {}", input))?
+        .with_context(|| format!("invalid input: {}", input))?
         .parse()?;
 
     Ok((begin, end))

aoc2019/src/day05.rs

@@ -1,7 +1,6 @@
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 use crate::intcode::Intcode;
 
@@ -20,18 +19,14 @@ fn part1(input: &str) -> Result<i64> {
     let mut intcode = Intcode::new(input)?;
     intcode.add_input(1);
     intcode.run()?;
-    intcode
+    intcode.get_last_output().context("intcode gave no output")
-        .get_last_output()
-        .ok_or_else(|| err!("intcode gave no output"))
 }
 
 fn part2(input: &str) -> Result<i64> {
     let mut intcode = Intcode::new(input)?;
     intcode.add_input(5);
     intcode.run()?;
-    intcode
+    intcode.get_last_output().context("intcode gave no output")
-        .get_last_output()
-        .ok_or_else(|| err!("intcode gave no output"))
 }
 
 #[cfg(test)]

aoc2019/src/day06.rs

@@ -3,8 +3,7 @@ use std::collections::HashSet;
 use std::fmt::Write;
 use std::iter;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 const INPUT: &str = include_str!("../input/day06.txt");
 
@@ -42,7 +41,7 @@ fn part1(input: &str) -> Result<u64> {
         .map(|line| {
             let paren = line
                 .find(')')
-                .ok_or_else(|| err!("couldn't find `)` in line: {}", line))?;
+                .with_context(|| format!("couldn't find `)` in line: {}", line))?;
             Ok((line[paren + 1..].to_string(), line[..paren].to_string()))
         })
         .collect::<Result<HashMap<String, String>>>()?;
@@ -61,7 +60,7 @@ fn part2(input: &str) -> Result<usize> {
         .map(|line| {
             let paren = line
                 .find(')')
-                .ok_or_else(|| err!("couldn't find `)` in line: {}", line))?;
+                .with_context(|| format!("couldn't find `)` in line: {}", line))?;
             Ok((line[paren + 1..].to_string(), line[..paren].to_string()))
         })
         .collect::<Result<HashMap<String, String>>>()?;

aoc2019/src/day07.rs

@@ -1,8 +1,7 @@
 use std::collections::VecDeque;
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{bail, Context, Result};
-use aoc::Result;
 
 use crate::intcode::{parse_memory, Intcode};
 
@@ -59,7 +58,7 @@ fn part1(input: &str) -> Result<i64> {
 
             output = intcode
                 .get_last_output()
-                .ok_or_else(|| err!("no output at end of pipeline!"))?;
+                .context("no output at end of pipeline!")?;
         }
 
         res = std::cmp::max(res, output);
@@ -114,7 +113,7 @@ fn part2(input: &str) -> Result<i64> {
                         res = std::cmp::max(res, signal);
                         break;
                     }
-                    None => return Err(err!("last amplifier halted without output")),
+                    None => bail!("last amplifier halted without output"),
                 };
             } else {
                 for out in last.output.iter() {

aoc2019/src/day08.rs

@@ -1,9 +1,7 @@
-use std::error::Error;
 use std::fmt::{self, Write};
 use std::str::FromStr;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 const IMG_WIDTH: usize = 25;
 const IMG_HEIGHT: usize = 6;
@@ -27,7 +25,7 @@ fn part1(image: &Image) -> Result<usize> {
         .layers
         .iter()
         .min_by_key(|l| l.pixels.iter().flatten().filter(|d| **d == 0).count())
-        .ok_or_else(|| err!("image had 0 layers..."))?;
+        .context("image had 0 layers...")?;
 
     let one_count = most_zero_layer
         .pixels
@@ -74,7 +72,7 @@ impl fmt::Display for Image {
 }
 
 impl FromStr for Image {
-    type Err = Box<dyn Error>;
+    type Err = anyhow::Error;
 
     fn from_str(s: &str) -> Result<Self> {
         let s = s.trim_end();

aoc2019/src/day09.rs

@@ -1,7 +1,6 @@
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 use crate::intcode::{parse_memory, Intcode};
 
@@ -25,7 +24,7 @@ fn part1(memory: Vec<i64>) -> Result<i64> {
     intcode.run()?;
     intcode
         .get_last_output()
-        .ok_or_else(|| err!("intcode output was empty!"))
+        .context("intcode output was empty!")
 }
 
 fn part2(memory: Vec<i64>) -> Result<i64> {
@@ -35,7 +34,7 @@ fn part2(memory: Vec<i64>) -> Result<i64> {
     intcode.run()?;
     intcode
         .get_last_output()
-        .ok_or_else(|| err!("intcode output was empty!"))
+        .context("intcode output was empty!")
 }
 
 #[cfg(test)]

aoc2019/src/day10.rs

@@ -1,8 +1,7 @@
 use std::collections::HashSet;
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 const INPUT: &str = include_str!("../input/day10.txt");
 
@@ -85,7 +84,7 @@ fn part1(input: &str) -> Result<usize> {
         };
     }
 
-    let best = best.ok_or_else(|| err!("zero asteroid provided"))?;
+    let best = best.context("zero asteroid provided")?;
     Ok(best.len())
 }
 

aoc2019/src/day11.rs

@@ -1,8 +1,7 @@
 use std::collections::HashMap;
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{bail, Result};
-use aoc::Result;
 
 use crate::intcode::Intcode;
 
@@ -40,7 +39,7 @@ fn part2(input: &str, res: &mut String) -> Result<()> {
 
 fn write_board(res: &mut String, board: HashMap<Position, bool>) -> Result<()> {
     if board.is_empty() {
-        return Err(err!("board was empty"));
+        bail!("board was empty");
     }
 
     let min_x = board.keys().map(|p| p.x).min().unwrap();
@@ -106,13 +105,13 @@ impl Robot {
                 match color {
                     0 => board.insert(self.pos, false),
                     1 => board.insert(self.pos, true),
-                    _ => return Err(err!("robot brain output different from 0 or 1")),
+                    _ => bail!("robot brain output different from 0 or 1"),
                 };
 
                 match direction {
                     0 => self.turn_left(),
                     1 => self.turn_right(),
-                    _ => return Err(err!("robot brain output different from 0 or 1")),
+                    _ => bail!("robot brain output different from 0 or 1"),
                 };
                 self.move_forward();
                 self.brain.output.clear();

aoc2019/src/day12.rs

@@ -1,9 +1,7 @@
-use std::error::Error;
 use std::fmt::Write;
 use std::str::FromStr;
 
-use aoc::err;
+use anyhow::{anyhow, Context, Result};
-use aoc::Result;
 
 const INPUT: &str = include_str!("../input/day12.txt");
 
@@ -178,7 +176,7 @@ fn part2(mut planets: Vec<Planet>) -> Result<usize> {
         }
     }
 
-    Err(err!("planets never reached the same state twice"))
+    Err(anyhow!("planets never reached the same state twice"))
 }
 
 #[derive(Clone)]
@@ -224,38 +222,38 @@ impl Planet {
 }
 
 impl FromStr for Planet {
-    type Err = Box<dyn Error>;
+    type Err = anyhow::Error;
 
     fn from_str(s: &str) -> Result<Self> {
         let x_equals = s
             .find("x=")
-            .ok_or_else(|| err!("couldn't find x value for planet: {}", s))?;
+            .with_context(|| format!("couldn't find x value for planet: {}", s))?;
 
         let comma = s
             .find(',')
-            .ok_or_else(|| err!("couldn't find comma after x value: {}", s))?;
+            .with_context(|| format!("couldn't find comma after x value: {}", s))?;
 
         let x = s[(x_equals + 2)..comma].parse()?;
         let s = &s[(comma + 1)..];
 
         let y_equals = s
             .find("y=")
-            .ok_or_else(|| err!("couldn't find y value for planet: {}", s))?;
+            .with_context(|| format!("couldn't find y value for planet: {}", s))?;
 
         let comma = s
             .find(',')
-            .ok_or_else(|| err!("couldn't find comma after y value: {}", s))?;
+            .with_context(|| format!("couldn't find comma after y value: {}", s))?;
 
         let y = s[(y_equals + 2)..comma].parse()?;
         let s = &s[(comma + 1)..];
 
         let z_equals = s
             .find("z=")
-            .ok_or_else(|| err!("couldn't find z value for planet: {}", s))?;
+            .with_context(|| format!("couldn't find z value for planet: {}", s))?;
 
         let bracket = s
             .find('>')
-            .ok_or_else(|| err!("couldn't find bracket after z value: {}", s))?;
+            .with_context(|| format!("couldn't find bracket after z value: {}", s))?;
 
         let z = s[(z_equals + 2)..bracket].parse()?;
 

aoc2019/src/day13.rs

@@ -1,8 +1,7 @@
 use std::collections::HashMap;
 use std::fmt::{self, Display, Write};
 
-use aoc::err;
+use anyhow::{bail, Result};
-use aoc::Result;
 
 use crate::intcode::{parse_memory, Intcode};
 
@@ -119,7 +118,7 @@ impl Tile {
             2 => Tile::Block,
             3 => Tile::Paddle,
             4 => Tile::Ball,
-            _ => return Err(err!("couldn't associate number with tile: {}", n)),
+            _ => bail!("couldn't associate number with tile: {}", n),
         };
 
         Ok(tile)

aoc2019/src/day14.rs

@@ -2,8 +2,7 @@ use std::cmp::Ordering;
 use std::collections::HashMap;
 use std::fmt::Write;
 
-use aoc::err;
+use anyhow::{Context, Result};
-use aoc::Result;
 
 const INPUT: &str = include_str!("../input/day14.txt");
 
@@ -22,7 +21,7 @@ fn parse_recipes(input: &str) -> Result<HashMap<String, Recipe>> {
     for line in input.lines() {
         let arrow = line
             .find(" => ")
-            .ok_or_else(|| err!("couldn't find arrow in line: {}", line))?;
+            .with_context(|| format!("couldn't find arrow in line: {}", line))?;
 
         let elems = &line[..arrow];
         let elems = elems
@@ -30,7 +29,7 @@ fn parse_recipes(input: &str) -> Result<HashMap<String, Recipe>> {
             .map(|elem| {
                 let space = elem
                     .find(' ')
-                    .ok_or_else(|| err!("couldn't find separator for elem {}", elem))?;
+                    .with_context(|| format!("couldn't find separator for elem {}", elem))?;
                 let amount = elem[..space].parse()?;
                 let name = &elem[(space + 1)..];
 
@@ -44,7 +43,7 @@ fn parse_recipes(input: &str) -> Result<HashMap<String, Recipe>> {
         let result = &line[(arrow + 4)..].trim_end();
         let space = result
             .find(' ')
-            .ok_or_else(|| err!("couldn't find separator for result {}", result))?;
+            .with_context(|| format!("couldn't find separator for result {}", result))?;
         let result_amount = result[..space].parse()?;
         let result_name = &result[(space + 1)..];
 
@@ -76,7 +75,7 @@ fn get_ore_cost(
     if in_stock < quantity {
         let recipe = recipes
             .get(&material)
-            .ok_or_else(|| err!("couldn't find recipe for {}", material))?;
+            .with_context(|| format!("couldn't find recipe for {}", material))?;
 
         let needed = quantity - in_stock;
         let num_reactions = (needed + recipe.produced - 1) / recipe.produced;

aoc2019/src/intcode/mod.rs

@@ -1,5 +1,4 @@
-use aoc::err;
+use anyhow::{anyhow, bail, Result};
-use aoc::Result;
 
 mod parameter;
 
@@ -8,7 +7,7 @@ use parameter::Parameter;
 pub fn parse_memory(s: &str) -> Result<Vec<i64>> {
     s.trim_end()
         .split(',')
-        .map(|x| x.parse().map_err(|e| err!("couldn't parse int: {}", e)))
+        .map(|x| x.parse().map_err(anyhow::Error::new))
         .collect()
 }
 
@@ -74,7 +73,7 @@ impl Intcode {
                 let dst = Parameter::new(mode3, self.memory.get(self.ip + 3).copied())?;
 
                 if let Parameter::Immediate(_) = dst {
-                    Err(err!("add: destination parameter can't be immediate"))
+                    Err(anyhow!("add: destination parameter can't be immediate"))
                 } else {
                     Ok(Opcode::Add(op1, op2, dst))
                 }
@@ -85,7 +84,9 @@ impl Intcode {
                 let dst = Parameter::new(mode3, self.memory.get(self.ip + 3).copied())?;
 
                 if let Parameter::Immediate(_) = dst {
-                    Err(err!("multiply: destination parameter can't be immediate"))
+                    Err(anyhow!(
+                        "multiply: destination parameter can't be immediate"
+                    ))
                 } else {
                     Ok(Opcode::Multiply(op1, op2, dst))
                 }
@@ -94,7 +95,7 @@ impl Intcode {
                 let dst = Parameter::new(mode1, self.memory.get(self.ip + 1).copied())?;
 
                 if let Parameter::Immediate(_) = dst {
-                    Err(err!("input: destination parameter can't be immediate"))
+                    Err(anyhow!("input: destination parameter can't be immediate"))
                 } else {
                     Ok(Opcode::Input(dst))
                 }
@@ -122,7 +123,9 @@ impl Intcode {
                 let dst = Parameter::new(mode3, self.memory.get(self.ip + 3).copied())?;
 
                 if let Parameter::Immediate(_) = dst {
-                    Err(err!("less than: destination parameter can't be immediate"))
+                    Err(anyhow!(
+                        "less than: destination parameter can't be immediate"
+                    ))
                 } else {
                     Ok(Opcode::LessThan(op1, op2, dst))
                 }
@@ -133,7 +136,7 @@ impl Intcode {
                 let dst = Parameter::new(mode3, self.memory.get(self.ip + 3).copied())?;
 
                 if let Parameter::Immediate(_) = dst {
-                    Err(err!("equals: destination parameter can't be immediate"))
+                    Err(anyhow!("equals: destination parameter can't be immediate"))
                 } else {
                     Ok(Opcode::Equals(op1, op2, dst))
                 }
@@ -144,14 +147,14 @@ impl Intcode {
                 Ok(Opcode::AdjustRelBase(offset))
             }
             99 => Ok(Opcode::Halt),
-            _ => Err(err!("unknown opcode: {}", opcode)),
+            _ => Err(anyhow!("unknown opcode: {}", opcode)),
         }
     }
 
     fn exec(&mut self) -> Result<bool> {
         loop {
             if self.ip >= self.memory.len() {
-                return Err(err!("reached end of program without halting"));
+                bail!("reached end of program without halting");
             }
 
             let opcode = self.get_opcode()?;
@@ -181,7 +184,7 @@ impl Intcode {
                     } else if self.wait_input {
                         break Ok(false);
                     } else {
-                        break Err(err!("tried to read input but it was empty"));
+                        break Err(anyhow!("tried to read input but it was empty"));
                     };
                     dst.set(input, &mut self.memory, self.relative_base)?;
 
@@ -197,7 +200,7 @@ impl Intcode {
                     let val = test.get(&mut self.memory, self.relative_base)?;
                     let dst = dst.get(&mut self.memory, self.relative_base)?;
                     if dst < 0 {
-                        return Err(err!("dst must be a valid address: {}", dst));
+                        bail!("dst must be a valid address: {}", dst);
                     }
 
                     if val != 0 {
@@ -210,7 +213,7 @@ impl Intcode {
                     let val = test.get(&mut self.memory, self.relative_base)?;
                     let dst = dst.get(&mut self.memory, self.relative_base)?;
                     if dst < 0 {
-                        return Err(err!("dst must be a valid address: {}", dst));
+                        bail!("dst must be a valid address: {}", dst);
                     }
 
                     if val == 0 {

aoc2019/src/intcode/parameter.rs

@@ -1,5 +1,4 @@
-use aoc::err;
+use anyhow::{anyhow, Context, Result};
-use aoc::Result;
 
 #[derive(Debug)]
 pub enum Parameter {
@@ -10,13 +9,13 @@ pub enum Parameter {
 
 impl Parameter {
     pub fn new(mode: i64, val: Option<i64>) -> Result<Self> {
-        let val = val.ok_or_else(|| err!("parameter value out of bounds"))?;
+        let val = val.context("parameter value out of bounds")?;
         let mode = mode % 10;
 
         match mode {
             0 => {
                 if val < 0 {
-                    Err(err!("negative value for position parameter: {}", val))
+                    Err(anyhow!("negative value for position parameter: {}", val))
                 } else {
                     let val = val as usize;
                     Ok(Parameter::Position(val))
@@ -24,7 +23,7 @@ impl Parameter {
             }
             1 => Ok(Parameter::Immediate(val)),
             2 => Ok(Parameter::Relative(val)),
-            _ => Err(err!("wrong mode for parameter: {}", mode)),
+            _ => Err(anyhow!("wrong mode for parameter: {}", mode)),
         }
     }
 
@@ -75,7 +74,7 @@ impl Parameter {
                 }
                 Ok(())
             }
-            Parameter::Immediate(_) => Err(err!("cannot write to immediate parameter")),
+            Parameter::Immediate(_) => Err(anyhow!("cannot write to immediate parameter")),
             Parameter::Relative(offset) => {
                 let address = relative_base.wrapping_add(*offset as usize);
                 let cell = memory.get_mut(address);

aoc2019/src/main.rs

@@ -1,5 +1,6 @@
+use anyhow::Result;
+
 use aoc::DayFunc;
-use aoc::Result;
 
 use aoc2019::day01;
 use aoc2019::day02;