tests/test-merge-revert

hgmerge: add cleanup functions

This patch adds functions cleanup, success and failure.
The last two of these should be used instead of exit.
Current code was changed to use them.
It also moves $HGTMP to the top of the file (it's used in the cleanup
function), changes the comment and removes now unneeded trap
in the diff+patch merge.

#!/bin/sh

mkdir t
cd t
hg init
echo "added file1" > file1
echo "added file2" > file2
hg add file1 file2
hg commit -m "added file1 and file2" -d "0 0" -u user
echo "changed file1" >> file1
hg commit -m "changed file1" -d "0 0" -u user
hg -q log
hg id
hg update -C 0
hg id
echo "changed file1" >> file1
hg id
hg revert
hg diff
hg status
hg id
hg update
hg diff
hg status
hg id
hg update -C 0
echo "changed file1" >> file1
HGMERGE=merge hg update
hg diff
hg status
hg id
hg revert
hg diff
hg status
hg id
hg revert -r tip
hg diff
hg status
hg id
hg update -C
hg diff
hg status
hg id
cd ..; /bin/rm -rf t