invalidate-changed-elm

#!/bin/bash
#
# usage: invalidate-old-elm "src directories space delimeted" BRANCH_TO_COMPARE OPTIONAL_BRANCH_TO_COMPARE_DEFAULTS_TO_HEAD


# git diff --name-only gives us relative paths from git root
# git rev-parse --show-prefix this fetches the current directory's relative prefix to the git root
# we remove the prefix
prefix=$(git rev-parse --show-prefix)
for file in $(git diff --name-only $2 $3 | grep .elm$)
# collect changed files and select only elms
do
  relative_path=$(printf $file | sed -e "s|$prefix||")
  for src_dir in $1
  do
    src_dir=$src_dir/
    if [[ $relative_path == $src_dir* ]]; then
      # remove the src_dir to find in elm-stuff
      elm=$(printf $relative_path | sed -e "s|$src_dir||")

      elmi=$(printf $elm | tr "/" "-")i
      find elm-stuff/build-artifacts -type f -name $elmi -exec rm {} \;
    fi
  done
done