test: use eatmydata for bitcoind and lightningd if available.

Before:	real	17m56.862s
After:	real	13m42.868s

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

daemon/test/scripts/vars.sh

@@ -1,10 +1,13 @@
 # Sourced by other scripts
 
+# Suppress sync if we can, for speedup.
+if which eatmydata >/dev/null; then EATMYDATA=eatmydata; fi
+
 STYLE=bitcoin
 DATADIR=/tmp/bitcoin-lightning
 CLI="bitcoin-cli -datadir=$DATADIR"
 REGTESTDIR=regtest
-DAEMON="bitcoind -datadir=$DATADIR"
+DAEMON="$EATMYDATA bitcoind -datadir=$DATADIR"
 
 findport()
 {

daemon/test/test.sh

@@ -40,12 +40,13 @@ ONE_HTLCS_FEE=$(( (338 + 32) * $FEE_RATE / 2000 * 2000))
 EXTRA_FEE=$(($ONE_HTLCS_FEE - $NO_HTLCS_FEE))
 
 # Always use valgrind if available.
-[ -n "$NO_VALGRIND" ] || PREFIX="valgrind -q --error-exitcode=7"
+PREFIX=$EATMYDATA
+[ -n "$NO_VALGRIND" ] || PREFIX="$EATMYDATA valgrind -q --error-exitcode=7"
 
 while [ $# != 0 ]; do
     case x"$1" in
 	x"--valgrind-vgdb")
-	    [ -n "$NO_VALGRIND" ] || PREFIX="valgrind --vgdb-error=1"
+	    [ -n "$NO_VALGRIND" ] || PREFIX="$EATMYDATA valgrind --vgdb-error=1"
 	    REDIR1="/dev/tty"
 	    REDIRERR1="/dev/tty"
 	    REDIR2="/dev/tty"