Add automated tests for some mods (#605)

Depends on mineunit from https://github.com/S-S-X/mineunit

mesecons, mesecons_mvps, mesecons_fpga, and mesecons_luacontroller are now tested.

.test_fixtures/mesecons.lua

@@ -0,0 +1,156 @@
+mineunit("core")
+mineunit("server")
+mineunit("voxelmanip")
+
+mineunit:set_current_modname("mesecons")
+mineunit:set_modpath("mesecons", "../mesecons")
+sourcefile("../mesecons/init")
+
+-- Utility node: this conductor is used to test the connectivity and state of adjacent wires.
+do
+	local off_spec = {conductor = {
+		state = mesecon.state.off,
+		rules = mesecon.rules.alldirs,
+		onstate = "mesecons:test_conductor_on",
+	}}
+	local on_spec = {conductor = {
+		state = mesecon.state.on,
+		rules = mesecon.rules.alldirs,
+		offstate = "mesecons:test_conductor_off",
+	}}
+	mesecon.register_node("mesecons:test_conductor", {
+		description = "Test Conductor",
+	}, {mesecons = off_spec}, {mesecons = on_spec})
+end
+
+-- Utility node: this receptor is used to test power sources.
+do
+	local off_spec = {receptor = {
+		state = mesecon.state.off,
+		rules = mesecon.rules.alldirs,
+	}}
+	local on_spec = {receptor = {
+		state = mesecon.state.on,
+		rules = mesecon.rules.alldirs,
+	}}
+	mesecon.register_node("mesecons:test_receptor", {
+		description = "Test Receptor",
+	}, {mesecons = off_spec}, {mesecons = on_spec})
+end
+
+-- Utility node: this effector is used to test circuit outputs.
+do
+	-- This is a list of actions in the form {<kind>, <pos>},
+	-- where <kind> is "on", "off", or "overheat".
+	mesecon._test_effector_events = {}
+	local function action_on(pos, node)
+		table.insert(mesecon._test_effector_events, {"on", pos})
+		node.param2 = node.param2 % 64 + 128 -- Turn on bit 7
+		minetest.swap_node(pos, node)
+	end
+	local function action_off(pos, node)
+		table.insert(mesecon._test_effector_events, {"off", pos})
+		node.param2 = node.param2 % 64 -- Turn off bit 7
+		minetest.swap_node(pos, node)
+	end
+	local function action_change(pos, node, rule_name, new_state)
+		if mesecon.do_overheat(pos) then
+			table.insert(mesecon._test_effector_events, {"overheat", pos})
+			minetest.remove_node(pos)
+			return
+		end
+		-- Set the value of a bit in param2 according to the rule name and new state.
+		local bit = tonumber(rule_name.name, 2)
+		local bits_above = node.param2 - node.param2 % (bit * 2)
+		local bits_below = node.param2 % bit
+		local bits_flipped = new_state == mesecon.state.on and bit or 0
+		node.param2 = bits_above + bits_flipped + bits_below
+		minetest.swap_node(pos, node)
+	end
+	minetest.register_node("mesecons:test_effector", {
+		description = "Test Effector",
+		mesecons = {effector = {
+			action_on = action_on,
+			action_off = action_off,
+			action_change = action_change,
+			rules = {
+				{x =  1, y =  0, z =  0, name = "000001"},
+				{x = -1, y =  0, z =  0, name = "000010"},
+				{x =  0, y =  1, z =  0, name = "000100"},
+				{x =  0, y = -1, z =  0, name = "001000"},
+				{x =  0, y =  0, z =  1, name = "010000"},
+				{x =  0, y =  0, z = -1, name = "100000"},
+			}
+		}},
+	})
+end
+
+-- Utility node: this conductor is used to test rotation.
+do
+	local get_rules = mesecon.horiz_rules_getter({{x = 1, y = 0, z = 0}, {x = -1, y = 0, z = 0}})
+	local off_spec = {conductor = {
+		state = mesecon.state.off,
+		rules = get_rules,
+		onstate = "mesecons:test_conductor_rot_on",
+	}}
+	local on_spec = {conductor = {
+		state = mesecon.state.on,
+		rules = get_rules,
+		offstate = "mesecons:test_conductor_rot_off",
+	}}
+	mesecon.register_node("mesecons:test_conductor_rot", {
+		description = "Rotatable Test Conductor",
+		on_rotate = mesecon.on_rotate_horiz,
+	}, {mesecons = off_spec}, {mesecons = on_spec})
+end
+
+-- Utility node: this is used to test multiple conductors within a single node.
+do
+	local mesecons_spec = {conductor = {
+		rules = {
+			{{x = 1, y = 0, z = 0}, {x = 0, y = -1, z = 0}},
+			{{x = 0, y = 1, z = 0}, {x = 0, y = 0, z = -1}},
+			{{x = 0, y = 0, z = 1}, {x = -1, y = 0, z = 0}},
+		},
+		states = {
+			"mesecons:test_multiconductor_off", "mesecons:test_multiconductor_001",
+			"mesecons:test_multiconductor_010", "mesecons:test_multiconductor_011",
+			"mesecons:test_multiconductor_100", "mesecons:test_multiconductor_101",
+			"mesecons:test_multiconductor_110", "mesecons:test_multiconductor_on",
+		},
+	}}
+	for _, state in ipairs(mesecons_spec.conductor.states) do
+		minetest.register_node(state, {
+			description = "Test Multiconductor",
+			mesecons = mesecons_spec,
+		})
+	end
+end
+
+mesecon._test_autoconnects = {}
+mesecon.register_autoconnect_hook("test", function(pos, node)
+	table.insert(mesecon._test_autoconnects, {pos, node})
+end)
+
+function mesecon._test_dig(pos)
+	local node = minetest.get_node(pos)
+	minetest.remove_node(pos)
+	mesecon.on_dignode(pos, node)
+end
+
+function mesecon._test_place(pos, node)
+	world.set_node(pos, node)
+	mesecon.on_placenode(pos, minetest.get_node(pos))
+end
+
+function mesecon._test_reset()
+	-- First let circuits settle by simulating many globalsteps.
+	for i = 1, 10 do
+		mineunit:execute_globalstep(60)
+	end
+	mesecon.queue.actions = {}
+	mesecon._test_effector_events = {}
+	mesecon._test_autoconnects = {}
+end
+
+mineunit:execute_globalstep(mesecon.setting("resumetime", 4) + 1)