source: vendor/grep/2.12/tests/backref

#! /bin/sh
# Test for backreferences and other things.
#
# Copyright (C) 2001, 2006, 2009-2012 Free Software Foundation, Inc.
#
# Copying and distribution of this file, with or without modification,
# are permitted in any medium without royalty provided the copyright
# notice and this notice are preserved.

. "${srcdir=.}/init.sh"; path_prepend_ ../src

failures=0

# checking for a palindrome
echo "radar" | grep -e '\(.\)\(.\).\2\1' > /dev/null 2>&1
if test $? -ne 0 ; then
        echo "Backref: palindrome, test #1 failed"
        failures=1
fi

# hit hard with the `Bond' tests
# For now, remove the `?' in the last parentheses, so that new glibc can do it.  --Stepan
echo "civic" | grep -E -e '^(.?)(.?)(.?)(.?)(.?)(.?)(.?)(.?)(.).?\9\8\7\6\5\4\3\2\1$' > /dev/null 2>&1
if test $? -ne 0 ; then
        echo "Options: Bond, test #2 failed"
        failures=1
fi

# backref are local should be error
echo "123" | grep -e 'a\(.\)' -e 'b\1' > /dev/null 2>&1
if test $? -ne 2 ; then
        echo "Backref: Backref not local, test #3 failed"
        failures=1
fi

# Pattern should fail
echo "123" | grep -e '[' -e ']' > /dev/null 2>&1
if test $? -ne 2 ; then
        echo "Backref: Compiled not local, test #4 failed"
        failures=1
fi

Exit $failures