Add hghave utility and run-tests.py support.
hghave detects system features like symlinks availability at run-time. Tests can be skipped by starting them with:
"$TESTDIR/hghave" symlink || exit 80
The 80 exit status triggers hghave output handling by run-tests.py. Also, tests output can be locally patched on the fly to match reference output.
#!/bin/sh
hg init test
cd test
mkdir da
echo foo > da/foo
echo foo > foo
hg ci -Ambase -d '0 0'
hg serve -p 20060 -d --pid-file=hg.pid
echo % manifest
("$TESTDIR/get-with-headers.py" localhost:20060 '/file/tip/?style=raw')
("$TESTDIR/get-with-headers.py" localhost:20060 '/file/tip/da?style=raw')
kill `cat hg.pid`