View Source Changelog


  • Make mix aoc.gen use example_string() instead of example_input(), which doesn't exist.



Dropping support for helper functions in solution modules

This update makes the "puzzle input" method introduced in 3.0.0 the only way to write solution modules. The old, "helper function" method is no longer supported.

The helper function method worked as follows:

aoc year, day do
  def p1, do: input_string() |> # Solve puzzle

The puzzle input method works as follows:

aoc year, day do
  def p1(input), do: input |> # solve puzzle

Input is provided through the use of the helpers in AOC.IEx.

The input method is preferred as it makes it easier to test your solution using different inputs without the need to modify any code. It also makes it significantly easier to write tests for your solution module.

Users who wish to keep using the helper method are advised to stick to version 3 of Advent of Code Utils.


This update adds optional support for generating unit test modules for your solution modules. You can now write:

aoc_test year, day do

Which will create an ExUnit.Case which tests your solution module. The generated case will automatically call the doctests of your solution module.

mix aoc.gen can now also generate this test code and add doctests to your solution module.

Detailed Changelog

  • Introduce AOC.aoc_test/4, AOC.Case.
  • Update mix aoc.gen to generate unit test files
  • Remove example_path/1, input_path/1, example_string/1, input_string/1, example_stream/1, input_stream/1 from AOC module.
  • Remove example_stream/1, input_stream/1 from AOC.IEx.
  • Rename fetch_example configuration to fetch_example? for consistency.


  • Optionally show the elapsed time when calling a p1, p2, p1i, p1e, p2i and p2e. This is done when the time_calls? configuration option is set to true.


  • AOC.IEx.mod/1 now calls Code.ensure_loaded!/1 to ensure the target module is loaded. This is done to prevent issues where p1e and p1i complain that the target module does not exist.


  • input_stream, input_string, example_stream and example_string now only trim trailing newlines, not significant whitespace.


  • Timezone support: the project now accepts a time_zone configuration setting which can be used to specify the time zone used by the input fetcher and iex helpers. This can be set to a time zone string, to :aoc or to :local (the default). :local uses the system time, as before, while :aoc uses the advent of code time zone (i.e. EST).


  • AOC.IEx has been reworked.
    • All functions accept an opts keyword list used to specify year or day when needed.
    • p1 and p2 now accept puzzle input as an argument, making it easier to switch between different inputs or examples.
    • Introduce p1e, p1i, p2e and p2i to facilitate calling p1 or p2 with example or puzzle input.
    • Introduce wrapper functions example_path/1, input_path/1, example_string/1, input_string/1, example_stream/1 and input_stream/1 to facilitate experimentation inside iex.
  • Update AOC documentation to reflect to new workflow.
  • Update mix aoc.gen to generate a template more suited to new workflow.



  • Update ex_doc, add typespecs to public functions.



  • Download example input when using mix aoc.get.
  • Add example_* functions to AOC module.


  • Make input_* functions public (def instead of defp) to facilitate debugging.


  • Initial stable release