perlpf

#!/bin/bash
declare -a tmp_files=()

doShowUsage () {
        cat <<USAGE >&2
Usage: $0 -[nx] <package> | -h
-n to show path to package which will be loaded by Perl in current/actual environment
-x to turn on BASH trace mode
-h to show this useful message
USAGE
}
[[ $1 ]] || { doShowUsage; exit 1; }
while getopts 'nxh' k; do
    case $k in
        n) flShowNative=1 ;;
        x) export TRACE=1; set -x ;;
        h) doShowUsage; exit 0 ;;
    esac
done
shift $((OPTIND-1))

pckFQName=$1

to_be_cleaned () {
        tmp_files+=($1)
}

perl_native () {
        local perlPackage=$1 resVarName=$2
        local pckFile=${3:-${perlPackage//:://}.pm}
        local ftmp
        ftmp=$(mktemp /tmp/XXXXXXXXXXXXXXXXXXXXX)
        to_be_cleaned $ftmp
        local res=$(perl -M"${pckFQName}" -e 'print $INC{q<'${pckFile}'>}, "\n"' 2>"${ftmp}")
        [[ $(stat -c %s "$ftmp") > 0 && $(<$ftmp) =~ locate\ ${pckFile//./\\.}\ in\ \@INC ]]
        local rc=$((1 - $?))
        (( $rc )) || eval "${resVarName}=\$res"
        return $rc
}

clean_on_exit () {
        local f
        for f in ${tmp_files[@]}; do
                rm -f "$f"
        done
}

trap clean_on_exit EXIT

perl_native $pckFQName pckFileFullPath || {
        echo 'no such package found';
        exit 1;
}

if [[ $flShowNative ]]; then
        echo "$pckFileFullPath"
else
        pckFile="${pckFQName//:://}.pm"
        rxPackage="^.*/${pckFile//./\\.}$"

        find $(perl -e 'print join(" ", @INC)') \
                -type f \
                -regextype posix-extended -regex "${rxPackage}" \
        2>/dev/null | sort | uniq
fi