make --style=compact look for map-cmdline.compact. change name of key in map file from changelog to changeset. rename command map files to start with map-cmdline. rename ui.logmap to ui.style in hgrc. now --style=foo does this: tries to open foo as file. tries as map-cmdline.foo in template path. tries as foo in template path.

#!/bin/sh

hg init
echo "nothing" > a
hg add a
hg commit -m ancestor -d "0 0"
echo "something" > a
hg commit -m branch1 -d "0 0"
hg co 0
echo "something else" > a
hg commit -m branch2 -d "0 0"
HGMERGE=merge; export HGMERGE
hg up -m 1
hg id
grep -Ev ">>>|<<<" a
hg status