Using nix to generate emoji based commit messages.

generate_script.nix

{ lib, ... }:
let
  inherit (builtins) fromJSON readFile;
  inherit (lib) mapAttrsToList strings concatStringsSep replaceStrings;
  inherit (strings) stringToCharacters head;

  # Read definitions to a list of definitions
  defs = let
    # Path to definitions
    source = ../../config/nvim/snippets/gitcommit.json;
    # Make name part of the definition to ease manipulation.
    transform = n: v: v // {
      name = n;
      body = replaceStrings ["$2" "\n"] ["" ""] v.body;
    };
  in mapAttrsToList transform (fromJSON (readFile source));

  # Get first char from name TODO: move to personal lib.
  fc = s: head (stringToCharacters s);

  # Format definition help message.
  help = {name, description, ...}: ''-${fc name} | ${name}: \"${description}\"'';

  # Switch case format
  case = {name, ...}: ''-${fc name}|${name}) ${name} $ARGS ;;'';

  # Format definition function definition. TODO: fix double new lines in commit
  # details
  function = { body, description, name, ... }:
  ''
  function ${name} {
    [[ "$1" = "help" ]] && echo "$(bold "${description}")" && exit 0;
    msg="${replaceStrings ["$1" "\n"] ["$@" ""] body}"
    # split on new line, needs \\n to be passed, support up to 3 new line chars
    array=(''${(ps:\n:)"$(echo $msg)"})
    git commit -m "''${array[1]}" -m "''${array[2]}" -m "''${array[3]}" -m "''${array[4]}"
  }
  '';
in
''
  #!/bin/zsh
  # DON'T EDIT: GENERATED FROM ${./commit.nix}

  function bold {
    echo "$(tput bold)$1$(tput sgr0)"
  }

  ${concatStringsSep "\n" (map function defs)}

  ARGS="''${@:2}"
  ALL="$@"
  case ''${@:1:1} in
    ${concatStringsSep "\n  " (map case defs)}
    -h|help)
      echo "$(bold 'Supported args:')\n\n${concatStringsSep "\n" (map help defs)}\n"
    ;;
    *) git commit -m "$ALL" ;;
  esac
''

generate_script.zsh

#!/bin/zsh
# DON'T EDIT: GENERATED FROM /nix/store/ygv8500sysjdc530r2ai7syksjmvq8f5-commit.nix

function bold {
  echo "$(tput bold)$1$(tput sgr0)"
}

function Release {
  [[ "$1" = "help" ]] && echo "$(bold "Release new version.")" && exit 0;
  msg="🚀 RELEASE: version $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}

function doc {
  [[ "$1" = "help" ]] && echo "$(bold "Add/edit/upgrade documentation regarding an aspect or feature.")" && exit 0;
  msg="📖 DOC: $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}

function fix {
  [[ "$1" = "help" ]] && echo "$(bold "Fixed bug or issue.")" && exit 0;
  msg="🛠 FIX: $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}

function improve {
  [[ "$1" = "help" ]] && echo "$(bold "Improved or enhanced feature or use case.")" && exit 0;
  msg="👌 IMPROVE: $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}

function new {
  [[ "$1" = "help" ]] && echo "$(bold "Add new feature or use case.")" && exit 0;
  msg="📦 NEW: $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}

function refactor {
  [[ "$1" = "help" ]] && echo "$(bold "General refactoring without effecting usage or performance.")" && exit 0;
  msg="📝 REFACTOR: $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}

function test {
  [[ "$1" = "help" ]] && echo "$(bold "Add/modified test suit or case.")" && exit 0;
  msg="🧬 TEST: $@"
  array=(${(ps:\n:)"$(echo $msg)"}) # split on new line, needs \\n to be passed
  git commit -m "${array[1]}" -m "${array[2]}" -m "${array[3]}"
}


ARGS="${@:2}"
ALL="$@"
case ${@:1:1} in
  -R|Release) Release $ARGS ;;
  -d|doc) doc $ARGS ;;
  -f|fix) fix $ARGS ;;
  -i|improve) improve $ARGS ;;
  -n|new) new $ARGS ;;
  -r|refactor) refactor $ARGS ;;
  -t|test) test $ARGS ;;
  -h|help)
    echo "$(bold 'Supported args:')\n\n-R | Release: \"Release new version.\"
-d | doc: \"Add/edit/upgrade documentation regarding an aspect or feature.\"
-f | fix: \"Fixed bug or issue.\"
-i | improve: \"Improved or enhanced feature or use case.\"
-n | new: \"Add new feature or use case.\"
-r | refactor: \"General refactoring without effecting usage or performance.\"
-t | test: \"Add/modified test suit or case.\"\n"
  ;;
  *) git commit -m "$ALL" ;;
esac

gitcommit.json

{
  "Release": {
    "prefix": ["release", "rels", "r"],
    "body": "🚀 RELEASE: version $1",
    "description": "Release new version."
  },
  "new": {
    "prefix": ["new", "n"],
    "body": "📦 NEW: $1",
    "description": "Add new feature or use case."
  },
  "doc": {
    "prefix": ["doc", "d"],
    "body": "📖 DOC: $1",
    "description": "Add/edit/upgrade documentation regarding an aspect or feature."
  },
  "improve": {
    "prefix": ["imp", "improve", "i"],
    "body": "👌 IMPROVE: $1",
    "description": "Improved or enhanced feature or use case."
  },
  "refactor": {
    "prefix": ["ref", "refactor", "r"],
    "body": "📝 REFACTOR: $1",
    "description": "General refactoring without effecting usage or performance."
  },
  "test": {
    "prefix": ["test", "t"],
    "body": "🧬 TEST: $1",
    "description": "Add/modified test suit or case."
  },
  "fix": {
    "prefix": ["fix", "f"],
    "body": "🛠 FIX: $1",
    "description": "Fixed bug or issue."
  }
}