Also find correct column width of wide characters.
Use unicodedata.east_asian_width() to determine wide/full width
characters if available. Otherwise, return character count as before.
#!/bin/sh
mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m test -d "1000000 0"
rm .hg/requires
hg tip
echo indoor-pool > .hg/requires
hg tip
true