#!/bin/bash
# Copyright 2015-2016 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

# Author: Ulrich Müller <ulm@gentoo.org>

refname=$1
oldrev=$2
newrev=$3

# Filenames must contain only the characters [A-Za-z0-9._+-] and must
# not begin with a dot, a hyphen, or a plus sign.
# https://devmanual.gentoo.org/general-concepts/tree/#what-belongs-in-the-tree%3F
# https://devmanual.gentoo.org/ebuild-writing/file-format/#file-naming-rules
export LC_ALL=C
regex='^([A-Za-z0-9_][A-Za-z0-9._+-]*/)*[A-Za-z0-9_][A-Za-z0-9._+-]*$'
exceptions=(
    .gitignore
    metadata/.gitignore
)

# git diff --name-only outputs \t, \n, \", and \\ for TAB, LF, ", and \,
# respectively. This is OK because the result won't be matched by the regex.
badfiles=$(git diff --name-only --diff-filter=ACR "${oldrev}" "${newrev}" \
    | grep -Ev -e "${regex}")

ret=0
IFS=$'\n'
for path in ${badfiles}; do
    for e in "${exceptions[@]}"; do
        [[ ${path} = "${e}" ]] && continue 2
    done
    echo "Path \"${path}\" violates file naming rules" >&2
    ret=1
done

exit ${ret}