Provide better error messages (#7)

* Provide better error messages

* Inline getSmallestMap

benches/query.bench.lua

@@ -4,11 +4,8 @@
 local ReplicatedStorage = game:GetService("ReplicatedStorage")
 local rgb = require(ReplicatedStorage.rgb)
 local Matter = require(ReplicatedStorage.DevPackages.Matter)
-local Rewrite = require(ReplicatedStorage.rewrite)
 local ecr = require(ReplicatedStorage.DevPackages.ecr)
 local newWorld = Matter.World.new()
-local world = Rewrite.World.new()
-local component = Rewrite.component
 
 local jecs = require(ReplicatedStorage.Lib)
 local mirror = require(ReplicatedStorage.mirror)
@@ -33,15 +30,6 @@ local B6 = ecr.component()
 local B7 = ecr.component()
 local B8 = ecr.component()
 
-local C1 = component()
-local C2 = component()
-local C3 = component()
-local C4 = component()
-local C5 = component()
-local C6 = component()
-local C7 = component()
-local C8 = component()
-
 local D1 = ecs:entity()
 local D2 = ecs:entity()
 local D3 = ecs:entity()
@@ -78,13 +66,11 @@ for i = 1, N do
 	local combination = ""
 	local n = newWorld:spawn()
 	local entity = ecs:entity()
-	local e = world:spawn()
 	local m = mcs:entity()
 
 	if flip() then 
 		combination ..= "B"
 		registry2:set(id, B2, {value = true}) 
-		world:insert(e, C2({ value = true}))
 		ecs:set(entity, D2, { value = true})
 		mcs:set(m, E2, { value = 2})
 		newWorld:insert(n, A2({value = true}))
@@ -92,7 +78,6 @@ for i = 1, N do
 	if flip() then 
 		combination ..= "C"
 		registry2:set(id, B3, {value = true}) 
-		world:insert(e, C3({ value = true}))
 		ecs:set(entity, D3, { value = true})
 		mcs:set(m, E3, { value = 2})
 		newWorld:insert(n, A3({value = true}))
@@ -100,7 +85,6 @@ for i = 1, N do
 	if flip() then 
 		combination ..= "D"
 		registry2:set(id, B4, {value = true}) 
-		world:insert(e, C4({ value = true}))
 		ecs:set(entity, D4, { value = true})
 		mcs:set(m, E4, { value = 2})
 
@@ -109,7 +93,6 @@ for i = 1, N do
 	if flip() then 
 		combination ..= "E"
 		registry2:set(id, B5, {value = true}) 
-		world:insert(e, C5({value = true}))
 		ecs:set(entity, D5, { value = true})
 		mcs:set(m, E5, { value = 2})
 
@@ -118,26 +101,20 @@ for i = 1, N do
 	if flip() then 
 		combination ..= "F"
 		registry2:set(id, B6, {value = true}) 
-		world:insert(e, C6({value = true}))
 		ecs:set(entity, D6, { value = true})
 		mcs:set(m, E6, { value = 2})
-
 		newWorld:insert(n, A6({value = true}))		
 	end
 	if flip() then 
 		combination ..= "G"
 		registry2:set(id, B7, {value = true}) 
-		world:insert(e, C7{ value = true})
 		ecs:set(entity, D7, { value = true})
 		mcs:set(m, E7, { value = 2})
-
-
 		newWorld:insert(n, A7({value = true}))		
 	end
 	if flip() then 
 		combination ..= "H"
 		registry2:set(id, B8, {value = true}) 
-		world:insert(e, C8{ value = true})
 		newWorld:insert(n, A8({value = true}))	
 		ecs:set(entity, D8, { value = true})
 		mcs:set(m, E8, { value = 2})
@@ -148,7 +125,6 @@ for i = 1, N do
 		combination = "A" .. combination
 		common += 1
 		registry2:set(id, B1, {value = true}) 
-		world:insert(e, C1{ value = true})
 		ecs:set(entity, D1, { value = true})
 		newWorld:insert(n, A1({value = true}))	
 		mcs:set(m, E1, { value = 2})
@@ -194,7 +170,7 @@ return {
 	end,	
 
 	Functions = {
-		Mater = function() 
+		Matter = function() 
 			local matched = 0
 			for entityId, firstComponent in newWorld:query(A1, A4, A6, A8) do
 				matched += 1

lib/init.lua

@@ -198,7 +198,7 @@ export type World = typeof(World.new())
 
 local function ensureArchetype(world: World, types, prev)
 	if #types < 1 then
-		
+		return world.ROOT_ARCHETYPE
 	end
 	local ty = hash(types)
 	local archetype = world.archetypeIndex[ty]
@@ -350,31 +350,31 @@ local function noop(): any
 	end
 end
 
-local function getSmallestMap(componentIndex, components) 
-	local s: any
-
-	for i, componentId in components do 
-		local map = componentIndex[componentId]
-		if s == nil or map.size < s.size then 
-			s = map	
-		end
-	end
-	
-	return s.sparse
-end
-
 function World.query(world: World, ...: i53): any
 	local compatibleArchetypes = {}
 	local components = { ... }
 	local archetypes = world.archetypes
 	local queryLength = #components
-	local firstArchetypeMap = getSmallestMap(world.componentIndex, components)
 
-	if not firstArchetypeMap then 
+	if queryLength == 0 then 
-		return noop()
+		error("Missing components")
 	end
 
-	for id in firstArchetypeMap do
+	local firstArchetypeMap
+	local componentIndex = world.componentIndex
+
+	for i, componentId in components do 
+		local map = componentIndex[componentId]
+		if not map then 
+			error(tostring(componentId).." has not been added to an entity")
+		end
+
+		if firstArchetypeMap == nil or map.size < firstArchetypeMap.size then 
+			firstArchetypeMap = map
+		end
+	end
+
+	for id in firstArchetypeMap.sparse do
 		local archetype = archetypes[id]
         local columns = archetype.columns
 		local archetypeRecords = archetype.records