Converts errors.on(:foo) to errors[:foo] when upgrading to Rails 3

convert_errors_on.sh

#!/usr/bin/env bash
#
# This small piece of sed converts the obj.errors.on(:foo) calls in 
# a single file to the new obj.errors[:foo] syntax as introduced in Rails 3

FILE=$1

function check_and_backup_file() {
  if [ -e "$FILE" ]; then
    cp $FILE $FILE.orig
  else
    echo "E: file '$FILE' does not exist"
    exit 1
  fi
}

function remove_backup_file() {
  if [ -e "$FILE.orig" ]; then
    rm $FILE.orig
	fi
}

function convert() {
	sed 's/\.errors\.on(:\([a-z_]*\))/\.errors\[:\1\]/g' <$FILE.orig >$FILE
}

function block_helpers() {
	sed 's/<% fields_for/<%= fields_for/' <$FILE.orig >$FILE
}

function human_name() {
	sed 's/\.human_name/.model_name.human/' <$FILE.orig >$FILE
}

function request_uri() {
	sed 's/request\.request_uri/request.fullpath/' <$FILE.orig >$FILE
}

function assert_template() {
	# assert_template "streets/index.html(.erb)" -> assert_template /^streets\/index\.html/
	# sed -E 's/assert_template "([a-z_]+)(\\/)([a-z_]+)\\.([a-z]+)(\\.erb)*"/assert_template \\/\\^\\1\\\\\\2\\3\\\\.\\4\\//g' <$FILE.orig >$FILE

	sed -E "s/assert_template (\"|')([a-z_]+)\.([a-z]+)(\.erb)*(\"|')/assert_template \/\^\2\\\.\3\//g" <$FILE.orig >$FILE
}

function usage() {
  echo "Usage: $0 FILENAME"
}

if [ -z "$FILE" ]; then
  usage
else
	check_and_backup_file
  # convert
	# block_helpers
	human_name
	# request_uri
	# assert_template
fi

remove_backup_file