tests/test-symlink-basic

localrepo._tag: add a seek before writing the new tag

Some systems require a seek (or flush) between read and write
operations on the same file object.

This should fix issue838.

#!/bin/sh

"$TESTDIR/hghave" symlink || exit 80

cleanpath()
{
    sed -e "s:/.*\(/test-symlink-basic/.*\):...\1:"
}

cat >> readlink.py <<EOF
import os
import sys

for f in sys.argv[1:]:
    print f, '->', os.readlink(f)
EOF

hg init a
cd a
ln -s nothing dangling
hg commit -m 'commit symlink without adding' -d '0 0' dangling 2>&1 | cleanpath
hg add dangling
hg commit -m 'add symlink' -d '0 0'

hg tip -v
hg manifest --debug
echo '% rev 0:'
python ../readlink.py dangling

rm dangling
ln -s void dangling
hg commit -m 'change symlink'
echo '% rev 1:'
python ../readlink.py dangling

echo '% modifying link'
rm dangling
ln -s empty dangling
python ../readlink.py dangling

echo '% reverting to rev 0:'
hg revert -r 0 -a
python ../readlink.py dangling

echo '% backups:'
python ../readlink.py *.orig

rm *.orig
hg up -C
echo '% copies'
hg cp -v dangling dangling2
hg st -Cmard
python ../readlink.py dangling dangling2