coffeerun - Wait for changes to a CoffeeScript file, compile it, and run it under either Mongo or Mac OS X's native JavaScript runtime.

coffeerun.sh

#!/bin/bash
# Wait for changes to a CoffeeScript file, compile it, and run it under either Mongo or Mac OS X's native JavaScript runtime.

set -o nounset
set -o errtrace
set -o errexit
set -o pipefail

usage() {
  cat <<END
Usage: $(basename $0) OPTIONS

  -h    Display this help text
  -m    Run under mongo (as in -m "server/mydb -u user -p pass") 
  -j    Run under JavaScriptCore (Mac OS)

END
echo ${1:-}
  exit 1
}

default_runtime="/System/Library/Frameworks/JavaScriptCore.framework/Versions/Current/Resources/jsc"

while getopts "j:m:f:" OPTION ; do
  case $OPTION in
    m)
      # OPTARG should be any other arguments to mongo, like database name.
      runtime="mongo $OPTARG"
      ;;
    j)
      runtime=$default_runtime
      ;;
    f)
      file=$OPTARG 
      ;;
    h)
      usage
      ;;
  esac
done

compiled=${file%.*}.js

function mtime() {
  while [[ ! -f $file ]] ; do
    sleep 0.025
    echo "... $file is gone ..." >&2
  done
  # -s is a feature of BSD stat(1). Sorry, GNU.
  eval $(/usr/bin/stat -s $file)
  echo $st_mtime
}

runtime=${runtime:-$default_runtime}
old_mtime=$(mtime $file)

echo -e "Watching for changes in $file; will run:\n  $runtime $compiled"
while :; do
  mtime=$(mtime $file)
  if [[ $mtime -gt $old_mtime ]] ; then
    time coffee -c $file && time $runtime $compiled || cat -n $compiled
    echo -e "Watching for changes in $file; will run:\n  $runtime $compiled"
  fi
  old_mtime=$mtime
  sleep 0.25
done