revlog: add a magic null revision to our index
We expand our index by one entry so that index[nullrev] points to a
unique entry, the null revision. This naturally eliminates numerous
extra tests in the performance-sensitive index access functions, most
of which are now trivial again.
Adding new entries is now done with insert(-1, e) rather than
append(e).
#!/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