Async environment for mods to do concurrent tasks (#11131)

3 files changed, 165 insertions, 0 deletions

diff --git a/games/devtest/mods/unittests/async_env.lua b/games/devtest/mods/unittests/async_env.lua
new file mode 100644
index 000000000..aff1fc4d9
--- /dev/null
+++ b/games/devtest/mods/unittests/async_env.lua
@@ -0,0 +1,149 @@
+-- helper
+
+core.register_async_dofile(core.get_modpath(core.get_current_modname()) ..
+	DIR_DELIM .. "inside_async_env.lua")
+
+local function deepequal(a, b)
+	if type(a) == "function" then
+		return type(b) == "function"
+	elseif type(a) ~= "table" then
+		return a == b
+	elseif type(b) ~= "table" then
+		return false
+	end
+	for k, v in pairs(a) do
+		if not deepequal(v, b[k]) then
+			return false
+		end
+	end
+	for k, v in pairs(b) do
+		if not deepequal(a[k], v) then
+			return false
+		end
+	end
+	return true
+end
+
+-- Object Passing / Serialization
+
+local test_object = {
+	name = "stairs:stair_glass",
+	type = "node",
+	groups = {oddly_breakable_by_hand = 3, cracky = 3, stair = 1},
+	description = "Glass Stair",
+	sounds = {
+		dig = {name = "default_glass_footstep", gain = 0.5},
+		footstep = {name = "default_glass_footstep", gain = 0.3},
+		dug = {name = "default_break_glass", gain = 1}
+	},
+	node_box = {
+		fixed = {
+			{-0.5, -0.5, -0.5, 0.5, 0, 0.5},
+			{-0.5, 0, 0, 0.5, 0.5, 0.5}
+		},
+		type = "fixed"
+	},
+	tiles = {
+		{name = "stairs_glass_split.png", backface_culling = true},
+		{name = "default_glass.png", backface_culling = true},
+		{name = "stairs_glass_stairside.png^[transformFX", backface_culling = true}
+	},
+	on_place = function(itemstack, placer)
+		return core.is_player(placer)
+	end,
+	sunlight_propagates = true,
+	is_ground_content = false,
+	light_source = 0,
+}
+
+local function test_object_passing()
+	local tmp = core.serialize_roundtrip(test_object)
+	assert(deepequal(test_object, tmp))
+
+	-- Circular key, should error
+	tmp = {"foo", "bar"}
+	tmp[tmp] = true
+	assert(not pcall(core.serialize_roundtrip, tmp))
+
+	-- Circular value, should error
+	tmp = {"foo"}
+	tmp[2] = tmp
+	assert(not pcall(core.serialize_roundtrip, tmp))
+end
+unittests.register("test_object_passing", test_object_passing)
+
+local function test_userdata_passing(_, pos)
+	-- basic userdata passing
+	local obj = table.copy(test_object.tiles[1])
+	obj.test = ItemStack("default:cobble 99")
+	local tmp = core.serialize_roundtrip(obj)
+	assert(type(tmp.test) == "userdata")
+	assert(obj.test:to_string() == tmp.test:to_string())
+
+	-- object can't be passed, should error
+	obj = core.raycast(pos, pos)
+	assert(not pcall(core.serialize_roundtrip, obj))
+
+	-- VManip
+	local vm = core.get_voxel_manip(pos, pos)
+	local expect = vm:get_node_at(pos)
+	local vm2 = core.serialize_roundtrip(vm)
+	assert(deepequal(vm2:get_node_at(pos), expect))
+end
+unittests.register("test_userdata_passing", test_userdata_passing, {map=true})
+
+-- Asynchronous jobs
+
+local function test_handle_async(cb)
+	-- Basic test including mod name tracking and unittests.async_test()
+	-- which is defined inside_async_env.lua
+	local func = function(x)
+		return core.get_last_run_mod(), _VERSION, unittests[x]()
+	end
+	local expect = {core.get_last_run_mod(), _VERSION, true}
+
+	core.handle_async(func, function(...)
+		if not deepequal(expect, {...}) then
+			cb("Values did not equal")
+		end
+		if core.get_last_run_mod() ~= expect[1] then
+			cb("Mod name not tracked correctly")
+		end
+
+		-- Test passing of nil arguments and return values
+		core.handle_async(function(a, b)
+			return a, b
+		end, function(a, b)
+			if b ~= 123 then
+				cb("Argument went missing")
+			end
+			cb()
+		end, nil, 123)
+	end, "async_test")
+end
+unittests.register("test_handle_async", test_handle_async, {async=true})
+
+local function test_userdata_passing2(cb, _, pos)
+	-- VManip: check transfer into other env
+	local vm = core.get_voxel_manip(pos, pos)
+	local expect = vm:get_node_at(pos)
+
+	core.handle_async(function(vm_, pos_)
+		return vm_:get_node_at(pos_)
+	end, function(ret)
+		if not deepequal(expect, ret) then
+			cb("Node data mismatch (one-way)")
+		end
+
+		-- VManip: test a roundtrip
+		core.handle_async(function(vm_)
+			return vm_
+		end, function(vm2)
+			if not deepequal(expect, vm2:get_node_at(pos)) then
+				cb("Node data mismatch (roundtrip)")
+			end
+			cb()
+		end, vm)
+	end, vm, pos)
+end
+unittests.register("test_userdata_passing2", test_userdata_passing2, {map=true, async=true})
diff --git a/games/devtest/mods/unittests/init.lua b/games/devtest/mods/unittests/init.lua
index 0754d507f..0608f2dd2 100644
--- a/games/devtest/mods/unittests/init.lua
+++ b/games/devtest/mods/unittests/init.lua
@@ -175,6 +175,7 @@ dofile(modpath .. "/misc.lua")
 dofile(modpath .. "/player.lua")
 dofile(modpath .. "/crafting.lua")
 dofile(modpath .. "/itemdescription.lua")
+dofile(modpath .. "/async_env.lua")
 
 --------------
 
diff --git a/games/devtest/mods/unittests/inside_async_env.lua b/games/devtest/mods/unittests/inside_async_env.lua
new file mode 100644
index 000000000..9774771f9
--- /dev/null
+++ b/games/devtest/mods/unittests/inside_async_env.lua
@@ -0,0 +1,15 @@
+unittests = {}
+
+core.log("info", "Hello World")
+
+function unittests.async_test()
+	assert(core == minetest)
+	-- stuff that should not be here
+	assert(not core.get_player_by_name)
+	assert(not core.set_node)
+	assert(not core.object_refs)
+	-- stuff that should be here
+	assert(ItemStack)
+	assert(core.registered_items[""])
+	return true
+end