Abort lightComplete test if no mapblocks are saved

- If the databse has no mapblocks in it, do not try
   and infinitely load one. For #17.

tests/moo.py

@@ -0,0 +1,25 @@
+import libminetest.map
+
+def main(map):
+	vessel = libminetest.map.MapVessel(map)
+	minpos = None
+	maxpos = None
+	for block in vessel.get_all_mapblock_ids():
+		print(block)
+		pos = libminetest.utils.getIntegerAsBlock(block)
+		if minpos is None:
+			minpos = pos
+		if maxpos is None:
+			maxpos = pos
+		minpos = libminetest.utils.Pos(min(pos.x,minpos.x),min(pos.y,minpos.y),min(pos.z,minpos.z))
+		maxpos = libminetest.utils.Pos(max(pos.x,maxpos.x),max(pos.y,maxpos.y),max(pos.z,maxpos.z))
+		#print(vessel.load(block))
+	print(minpos)
+	print(maxpos)
+
+	dimens = len(vessel.get_all_mapblock_ids())
+	print("There are {0} blocks currently generated and stored".format(dimens))
+	vessel.close()
+
+if __name__ == "__main__":
+	main("/home/limefox/.minetest/worlds/Creative/map.sqlite")

tests/test.py

@@ -242,8 +242,13 @@ def testLightingDone(map):
 	import random
 	db = libminetest.map.MapInterface(map)
 	i = 0
+	blocks = db.container.get_all_mapblock_ids()
+	if len(blocks) == 0:
+		print("!!!> Lighting test cannot proceed : no blocks generated")
+		return
+
 	while True:
-		i = random.randrange(-4096, 4096)
+		i = random.choice(blocks)
 		if db.load_mapblock(i):
 			break