20x faster replacement for "npm run"

fast-npm-run.sh

# 20x faster replacement for "npm run"
# - It supports scripts executing a built-in shell function
# - It supports scripts executing a binary found in PATH
# - It supports scripts executing a binary found in node_modules
# - It supports passing arguments and options to scripts
# - It supports reading scripts either via ripgrep (fast) or via jq (slower, but safer)
# - It adds ./node_modules/.bin to the $PATH
# - It handles gracefully when a script has not been found
# - It handles gracefully when "&", "&&", "|", "||", or ENV variables are used, falling back to "npm run"

#TODO: Make this work with "&&" too, which would enable this to speed up significantly more scripts
#TODO: Find something that's just as fast as ripgrep, but just as safe as jq

function run () {
  local jq_mode=false # Set this to true if you don't want to live dangerously
  local script_name="${1:-null}"
  if [ "$jq_mode" = true ] || ! command -v rg &> /dev/null; then # ~2x slower, but super safe
    local script_value="$(jq -r ".scripts[\"$1\"]" package.json)"
  else # Fast
    local script_value=$(rg -o "\"$script_name\":\s*\"(.*)\",?$" -r '$1' < package.json)
  fi
  if [ $script_value = "null" ]; then
    echo "Missing script: \"$script_name\""
    return 1
  else
    shift
    local script_args=$@
    if echo "$script_value" | grep -q '\([&|()]\|[A-Z]=\)'; then # Fallback path
      npm run $script_name $script_args
    else # Fast path
      local npm_bin_path=$(realpath ./node_modules/.bin || echo '')
      if [ -n "$npm_bin_path" ]; then
        export PATH="./node_modules/.bin:$PATH"
      fi
      echo "\n> $script_value\n"
      local bin_name=${script_value%% *}
      local bin_args=${script_value#* }
      if [ $script_value = $bin_name ]; then
        bin_args=""
      fi
      if type $bin_name | grep -q 'shell builtin'; then
        eval $bin_name $bin_args $script_args
      else
        local bin_path=$(which $bin_name &> /dev/null && which $bin_name || echo "./node_modules/.bin/$bin_name")
        eval $bin_path $bin_args $script_args
      fi
    fi
  fi
}