#!/bin/sh
#
# Commit hook designed to keep tab characters out of ASDF.
# Written by Daniel Herring, released into the public domain.

if git-rev-parse --verify HEAD >/dev/null 2>&1
then
	against=HEAD
else
	# Initial commit: diff against an empty tree object
	against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
fi

for f in $(git diff --cached --name-only --diff-filter=AM $against)
do
  case "$f" in #(
  *.asd | *.lisp | *.script)
    if (git diff --cached -p $against "$f" | grep '	' > /dev/null 2>&1)
    then
      echo "Error: This git repository disallows the #\Tab character in lisp files."
      echo "Only spaces should be used for indenting lisp code."
      echo "In emacs, 'M-x untabify' and (setq indent-tabs-mode nil) may help."
      echo
      echo "First offending file and lines:"
      echo "$f"
      (git diff --cached -p $against "$f" | grep '	' 2>&1)
      exit 1
    fi
    ;;
  esac
done

# nothing else to complain about
exit 0