⚠️ Note: This tool is under active development. I built in in a couple hours with no automated tests. Things may change between versions!

A little CLI tool that scaffolds and runs Advent of Code solutions in Ruby.

This project is heavily based on advent-of-code-rust. Go check it out!

Add this line to your application's Gemfile:

gem "advent_of_code_cli"

Run bundle install.

This command will set up the files for any day of Advent of Code. It takes a number between 1 and 25 as an argument.

bundle exec aoc_cli scaffold 1

This will result in the following output:

Creating file: 01.rb...
Creating inputs directory...
Creating file: inputs/01.txt...
Creating examples directory...
Creating examples/01 directory...

The file 01.rb will have the following structure:

module Day01
  class << self
    def part_one(input)
      raise NotImplementedError
    end

    def part_two(input)
      raise NotImplementedError
    end
  end
end

...where input is an Array[String] of all the lines without newlines.

I would love to make this structure configurable in the future.

This command will download the input for a given day.

In order for this to work, you must provide your Advent of Code session cookie to the program in an environment variable:

export AOC_COOKIE=your-cookie

To obtain the cookie, sign into Advent of Code through your browser, then use the developer tools to examine the headers for a page request. The cookie: header should contain a value like session=a1b2c3.... The part from a1b2c3... onwards is what your need for AOC_COOKIE.

Once the environment variable is set, you can request your personal input for any day.

bundle exec aoc_cli download 1

This will create the following output:

Fetching input...
Writing input to inputs/01.txt...
Done!

By default, the CLI will request the input for this year, but you can request previous years' input by passing a --year flag.

bundle exec aoc_cli download 1 --year 2021

This command will run your solution to a certain day's puzzle.

bundle exec aoc_cli solve 1

This will create the following output:

Reading input...
Loading solution...

Running part one...
Part one result: 10000
Took 0.000259 seconds to solve

Running part two...
Part two result: 10000
Took 0.00026 seconds to solve

Done!

This command expects files to be in the format provided by the scaffold command. Once again, I would love to make this configurable but haven't gotten around to it yet.

It is often helpful to run our solutions against example input. The example command can help you create and run examples of your own invention.

You can create a new file for example input by running the following command:

bundle exec aoc_cli example new 1 A

The first argument specifies the day, and the second argument is the name of the example. You may choose whatever name you'd like.

This will generate the following output:

Creating examples/01/A.txt...
Creating examples/01/A_expected.yml...
Done!

• examples/01/A.txt is a blank text file where you can enter your own input for the problem.
• examples/01/A_expected.yml is a YAML file with the following content:

part_one: ~
part_two: ~

Replace the two tildes (~) with the expected result of running your solution against the example input provided.

You can check your solution against an example with the following command:

bundle exec aoc_cli example solve 1 A

This will output the following:

Reading input...
Loading solution...

Running part one with example A...
Part one result: 1034 ✅
Took 0.000259 seconds to solve

Running part two with example A...
Part two result: 7934 ✅
Took 0.000253 seconds to solve

Issues and code contributions are welcome! Happy Advent of Code to all who celebrate! 🎁