Find unused subs in project

perl_unused_subs.sh

#!/bin/bash

# Usage:
#   ./perl_unused_subs.sh project_dir
#   ./perl_unused_subs.sh project_dir another_project_dir_that_can_use_prev
#   ACK_OPTIONS="-h"  && ./perl_unused_subs.sh project_dir

INC_DIRS=$@
TMP_FILE="$$.pl"

if [[ $INC_DIRS == '' ]]; then
    echo 'project/includes dir(s) required'
    exit
fi

# find all .pl & pm and join in one file
find $INC_DIRS -name '*.pl' -or -name '*.pm' -exec cat '{}' ';' > $TMP_FILE

if [[ ! -e $TMP_FILE ]]; then
    echo 'Error: Cant find tmp file!'
    exit
fi

# fixes & strips
perl -i -p -e 's:^package :\n\npackage :g' $TMP_FILE
perl -i -p -e 's:^__END__:\n:g' $TMP_FILE
perl -i -p -e 's:^\s*#.+?\n::g' $TMP_FILE

subs=`grep -E "^sub " $TMP_FILE | cut -d' ' -f2 | sort -u`
res=()
for sub in ${subs}
do
    grep ${sub} $TMP_FILE | grep -vq "sub ${sub}"
    if [ "$?" == "1" ]
    then
        res=("${res[@]}" "${sub}")
    fi
done
if [ ${#res[@]} == 0 ]
then
    echo "All subroutines in $INC_DIRS appear to be used"
else
    echo "In $INC_DIRS apparently unused:"
    for sub in ${res[@]}
    do
        ack --env --type=perl $sub $INC_DIRS
    done
fi

rm $TMP_FILE