Add checks for programs which are required for the test suite to run. All prerequisite programs are checked for existance, and if any are missing, a list of missing programs is printed, and the test suite is aborted. All programs currently used in the tests, except those in core-utils, are checked.

#!/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