Initial commit

builtin/common/tests/misc_helpers_spec.lua

@@ -0,0 +1,173 @@
+_G.core = {}
+_G.vector = {metatable = {}}
+dofile("builtin/common/vector.lua")
+dofile("builtin/common/misc_helpers.lua")
+
+describe("string", function()
+	it("trim()", function()
+		assert.equal("foo bar", string.trim("\n \t\tfoo bar\t "))
+	end)
+
+	describe("split()", function()
+		it("removes empty", function()
+			assert.same({ "hello" }, string.split("hello"))
+			assert.same({ "hello", "world" }, string.split("hello,world"))
+			assert.same({ "hello", "world" }, string.split("hello,world,,,"))
+			assert.same({ "hello", "world" }, string.split(",,,hello,world"))
+			assert.same({ "hello", "world", "2" }, string.split("hello,,,world,2"))
+			assert.same({ "hello ", " world" }, string.split("hello :| world", ":|"))
+		end)
+
+		it("keeps empty", function()
+			assert.same({ "hello" }, string.split("hello", ",", true))
+			assert.same({ "hello", "world" }, string.split("hello,world", ",", true))
+			assert.same({ "hello", "world", "" }, string.split("hello,world,", ",", true))
+			assert.same({ "hello", "", "", "world", "2" }, string.split("hello,,,world,2", ",", true))
+			assert.same({ "", "", "hello", "world", "2" }, string.split(",,hello,world,2", ",", true))
+			assert.same({ "hello ", " world | :" }, string.split("hello :| world | :", ":|"))
+		end)
+
+		it("max_splits", function()
+			assert.same({ "one" }, string.split("one", ",", true, 2))
+			assert.same({ "one,two,three,four" }, string.split("one,two,three,four", ",", true, 0))
+			assert.same({ "one", "two", "three,four" }, string.split("one,two,three,four", ",", true, 2))
+			assert.same({ "one", "", "two,three,four" }, string.split("one,,two,three,four", ",", true, 2))
+			assert.same({ "one", "two", "three,four" }, string.split("one,,,,,,two,three,four", ",", false, 2))
+		end)
+
+		it("pattern", function()
+			assert.same({ "one", "two" }, string.split("one,two", ",", false, -1, true))
+			assert.same({ "one", "two", "three" }, string.split("one2two3three", "%d", false, -1, true))
+		end)
+	end)
+end)
+
+describe("privs", function()
+	it("from string", function()
+		assert.same({ a = true, b = true }, core.string_to_privs("a,b"))
+	end)
+
+	it("to string", function()
+		assert.equal("one", core.privs_to_string({ one=true }))
+
+		local ret = core.privs_to_string({ a=true, b=true })
+		assert(ret == "a,b" or ret == "b,a")
+	end)
+end)
+
+describe("pos", function()
+	it("from string", function()
+		assert.equal(vector.new(10, 5.1, -2), core.string_to_pos("10.0, 5.1, -2"))
+		assert.equal(vector.new(10, 5.1, -2), core.string_to_pos("( 10.0, 5.1, -2)"))
+		assert.is_nil(core.string_to_pos("asd, 5, -2)"))
+	end)
+
+	it("to string", function()
+		assert.equal("(10.1,5.2,-2.3)", core.pos_to_string({ x = 10.1, y = 5.2, z = -2.3}))
+	end)
+end)
+
+describe("area parsing", function()
+	describe("valid inputs", function()
+		it("accepts absolute numbers", function()
+			local p1, p2 = core.string_to_area("(10.0, 5, -2) (  30.2 4 -12.53)")
+			assert(p1.x == 10 and p1.y == 5 and p1.z == -2)
+			assert(p2.x == 30.2 and p2.y == 4 and p2.z == -12.53)
+		end)
+
+		it("accepts relative numbers", function()
+			local p1, p2 = core.string_to_area("(1,2,3) (~5,~-5,~)", {x=10,y=10,z=10})
+			assert(type(p1) == "table" and type(p2) == "table")
+			assert(p1.x == 1 and p1.y == 2 and p1.z == 3)
+			assert(p2.x == 15 and p2.y == 5 and p2.z == 10)
+
+			p1, p2 = core.string_to_area("(1 2 3) (~5 ~-5 ~)", {x=10,y=10,z=10})
+			assert(type(p1) == "table" and type(p2) == "table")
+			assert(p1.x == 1 and p1.y == 2 and p1.z == 3)
+			assert(p2.x == 15 and p2.y == 5 and p2.z == 10)
+		end)
+	end)
+	describe("invalid inputs", function()
+		it("rejects too few numbers", function()
+			local p1, p2 = core.string_to_area("(1,1) (1,1,1,1)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+		end)
+
+		it("rejects too many numbers", function()
+			local p1, p2 = core.string_to_area("(1,1,1,1) (1,1,1,1)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+		end)
+
+		it("rejects nan & inf", function()
+			local p1, p2 = core.string_to_area("(1,1,1) (1,1,nan)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(1,1,1) (1,1,~nan)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(1,1,1) (1,~nan,1)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(1,1,1) (1,1,inf)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(1,1,1) (1,1,~inf)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(1,1,1) (1,~inf,1)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(nan,nan,nan) (nan,nan,nan)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(nan,nan,nan) (nan,nan,nan)")
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(inf,inf,inf) (-inf,-inf,-inf)", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(inf,inf,inf) (-inf,-inf,-inf)")
+			assert(p1 == nil and p2 == nil)
+		end)
+
+		it("rejects words", function()
+			local p1, p2 = core.string_to_area("bananas", {x=1,y=1,z=1})
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("bananas", "foobar")
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("bananas")
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(bananas,bananas,bananas)")
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(bananas,bananas,bananas) (bananas,bananas,bananas)")
+			assert(p1 == nil and p2 == nil)
+		end)
+
+		it("requires parenthesis & valid numbers", function()
+			local p1, p2 = core.string_to_area("(10.0, 5, -2  30.2,   4, -12.53")
+			assert(p1 == nil and p2 == nil)
+
+			p1, p2 = core.string_to_area("(10.0, 5,) -2  fgdf2,   4, -12.53")
+			assert(p1 == nil and p2 == nil)
+		end)
+	end)
+end)
+
+describe("table", function()
+	it("indexof()", function()
+		assert.equal(1, table.indexof({"foo", "bar"}, "foo"))
+		assert.equal(-1, table.indexof({"foo", "bar"}, "baz"))
+	end)
+end)
+
+describe("formspec_escape", function()
+	it("escapes", function()
+		assert.equal(nil, core.formspec_escape(nil))
+		assert.equal("", core.formspec_escape(""))
+		assert.equal("\\[Hello\\\\\\[", core.formspec_escape("[Hello\\["))
+	end)
+end)

builtin/common/tests/serialize_spec.lua

@@ -0,0 +1,189 @@
+_G.core = {}
+_G.vector = {metatable = {}}
+
+_G.setfenv = require 'busted.compatibility'.setfenv
+
+dofile("builtin/common/serialize.lua")
+dofile("builtin/common/vector.lua")
+
+-- Supports circular tables; does not support table keys
+-- Correctly checks whether a mapping of references ("same") exists
+-- Is significantly more efficient than assert.same
+local function assert_same(a, b, same)
+	same = same or {}
+	if same[a] or same[b] then
+		assert(same[a] == b and same[b] == a)
+		return
+	end
+	if a == b then
+		return
+	end
+	if type(a) ~= "table" or type(b) ~= "table" then
+		assert(a == b)
+		return
+	end
+	same[a] = b
+	same[b] = a
+	local count = 0
+	for k, v in pairs(a) do
+		count = count + 1
+		assert(type(k) ~= "table")
+		assert_same(v, b[k], same)
+	end
+	for _ in pairs(b) do
+		count = count - 1
+	end
+	assert(count == 0)
+end
+
+local x, y = {}, {}
+local t1, t2 = {x, x, y, y}, {x, y, x, y}
+assert.same(t1, t2) -- will succeed because it only checks whether the depths match
+assert(not pcall(assert_same, t1, t2)) -- will correctly fail because it checks whether the refs match
+
+describe("serialize", function()
+	local function assert_preserves(value)
+		local preserved_value = core.deserialize(core.serialize(value))
+		assert_same(value, preserved_value)
+	end
+	it("works", function()
+		assert_preserves({cat={sound="nyan", speed=400}, dog={sound="woof"}})
+	end)
+
+	it("handles characters", function()
+		assert_preserves({escape_chars="\n\r\t\v\\\"\'", non_european="θשׁ٩∂"})
+	end)
+
+	it("handles NaN & infinities", function()
+		local nan = core.deserialize(core.serialize(0/0))
+		assert(nan ~= nan)
+		assert_preserves(math.huge)
+		assert_preserves(-math.huge)
+	end)
+
+	it("handles precise numbers", function()
+		assert_preserves(0.2695949158945771)
+	end)
+
+	it("handles big integers", function()
+		assert_preserves(269594915894577)
+	end)
+
+	it("handles recursive structures", function()
+		local test_in = { hello = "world" }
+		test_in.foo = test_in
+		assert_preserves(test_in)
+	end)
+
+	it("handles cross-referencing structures", function()
+		local test_in = {
+			foo = {
+				baz = {
+					{}
+				},
+			},
+			bar = {
+				baz = {},
+			},
+		}
+
+		test_in.foo.baz[1].foo = test_in.foo
+		test_in.foo.baz[1].bar = test_in.bar
+		test_in.bar.baz[1] = test_in.foo.baz[1]
+
+		assert_preserves(test_in)
+	end)
+
+	it("strips functions in safe mode", function()
+		local test_in = {
+			func = function(a, b)
+				error("test")
+			end,
+			foo = "bar"
+		}
+		setfenv(test_in.func, _G)
+
+		local str = core.serialize(test_in)
+		assert.not_nil(str:find("loadstring"))
+
+		local test_out = core.deserialize(str, true)
+		assert.is_nil(test_out.func)
+		assert.equals(test_out.foo, "bar")
+	end)
+
+	it("vectors work", function()
+		local v = vector.new(1, 2, 3)
+		assert_preserves({v})
+		assert_preserves(v)
+
+		-- abuse
+		v = vector.new(1, 2, 3)
+		v.a = "bla"
+		assert_preserves(v)
+	end)
+
+	it("handles keywords as keys", function()
+		assert_preserves({["and"] = "keyword", ["for"] = "keyword"})
+	end)
+
+	describe("fuzzing", function()
+		local atomics = {true, false, math.huge, -math.huge} -- no NaN or nil
+		local function atomic()
+			return atomics[math.random(1, #atomics)]
+		end
+		local function num()
+			local sign = math.random() < 0.5 and -1 or 1
+			-- HACK math.random(a, b) requires a, b & b - a to fit within a 32-bit int
+			-- Use two random calls to generate a random number from 0 - 2^50 as lower & upper 25 bits
+			local val = math.random(0, 2^25) * 2^25 + math.random(0, 2^25 - 1)
+			local exp = math.random() < 0.5 and 1 or 2^(math.random(-120, 120))
+			return sign * val * exp
+		end
+		local function charcodes(count)
+			if count == 0 then return end
+			return math.random(0, 0xFF), charcodes(count - 1)
+		end
+		local function str()
+			return string.char(charcodes(math.random(0, 100)))
+		end
+		local primitives = {atomic, num, str}
+		local function primitive()
+			return primitives[math.random(1, #primitives)]()
+		end
+		local function tab(max_actions)
+			local root = {}
+			local tables = {root}
+			local function random_table()
+				return tables[math.random(1, #tables)]
+			end
+			for _ = 1, math.random(1, max_actions) do
+				local tab = random_table()
+				local value
+				if math.random() < 0.5 then
+					if math.random() < 0.5 then
+						value = random_table()
+					else
+						value = {}
+						table.insert(tables, value)
+					end
+				else
+					value = primitive()
+				end
+				tab[math.random() < 0.5 and (#tab + 1) or primitive()] = value
+			end
+			return root
+		end
+		it("primitives work", function()
+			for _ = 1, 1e3 do
+				assert_preserves(primitive())
+			end
+		end)
+		it("tables work", function()
+			for _ = 1, 100 do
+				local fuzzed_table = tab(1e3)
+				assert_same(fuzzed_table, table.copy(fuzzed_table))
+				assert_preserves(fuzzed_table)
+			end
+		end)
+	end)
+end)

builtin/common/tests/vector_spec.lua

@@ -0,0 +1,465 @@
+_G.vector = {metatable = {}}
+dofile("builtin/common/vector.lua")
+
+describe("vector", function()
+	describe("new()", function()
+		it("constructs", function()
+			assert.same({x = 0, y = 0, z = 0}, vector.new())
+			assert.same({x = 1, y = 2, z = 3}, vector.new(1, 2, 3))
+			assert.same({x = 3, y = 2, z = 1}, vector.new({x = 3, y = 2, z = 1}))
+
+			assert.is_true(vector.check(vector.new()))
+			assert.is_true(vector.check(vector.new(1, 2, 3)))
+			assert.is_true(vector.check(vector.new({x = 3, y = 2, z = 1})))
+
+			local input = vector.new({ x = 3, y = 2, z = 1 })
+			local output = vector.new(input)
+			assert.same(input, output)
+			assert.equal(input, output)
+			assert.is_false(rawequal(input, output))
+			assert.equal(input, input:new())
+		end)
+
+		it("throws on invalid input", function()
+			assert.has.errors(function()
+				vector.new({ x = 3 })
+			end)
+
+			assert.has.errors(function()
+				vector.new({ d = 3 })
+			end)
+		end)
+	end)
+
+	it("zero()", function()
+		assert.same({x = 0, y = 0, z = 0}, vector.zero())
+		assert.same(vector.new(), vector.zero())
+		assert.equal(vector.new(), vector.zero())
+		assert.is_true(vector.check(vector.zero()))
+	end)
+
+	it("copy()", function()
+		local v = vector.new(1, 2, 3)
+		assert.same(v, vector.copy(v))
+		assert.same(vector.new(v), vector.copy(v))
+		assert.equal(vector.new(v), vector.copy(v))
+		assert.is_true(vector.check(vector.copy(v)))
+	end)
+
+	it("indexes", function()
+		local some_vector = vector.new(24, 42, 13)
+		assert.equal(24, some_vector[1])
+		assert.equal(24, some_vector.x)
+		assert.equal(42, some_vector[2])
+		assert.equal(42, some_vector.y)
+		assert.equal(13, some_vector[3])
+		assert.equal(13, some_vector.z)
+
+		some_vector[1] = 100
+		assert.equal(100, some_vector.x)
+		some_vector.x = 101
+		assert.equal(101, some_vector[1])
+
+		some_vector[2] = 100
+		assert.equal(100, some_vector.y)
+		some_vector.y = 102
+		assert.equal(102, some_vector[2])
+
+		some_vector[3] = 100
+		assert.equal(100, some_vector.z)
+		some_vector.z = 103
+		assert.equal(103, some_vector[3])
+	end)
+
+	it("direction()", function()
+		local a = vector.new(1, 0, 0)
+		local b = vector.new(1, 42, 0)
+		assert.equal(vector.new(0, 1, 0), vector.direction(a, b))
+		assert.equal(vector.new(0, 1, 0), a:direction(b))
+	end)
+
+	it("distance()", function()
+		local a = vector.new(1, 0, 0)
+		local b = vector.new(3, 42, 9)
+		assert.is_true(math.abs(43 - vector.distance(a, b)) < 1.0e-12)
+		assert.is_true(math.abs(43 - a:distance(b)) < 1.0e-12)
+		assert.equal(0, vector.distance(a, a))
+		assert.equal(0, b:distance(b))
+	end)
+
+	it("length()", function()
+		local a = vector.new(0, 0, -23)
+		assert.equal(0, vector.length(vector.new()))
+		assert.equal(23, vector.length(a))
+		assert.equal(23, a:length())
+	end)
+
+	it("normalize()", function()
+		local a = vector.new(0, 0, -23)
+		assert.equal(vector.new(0, 0, -1), vector.normalize(a))
+		assert.equal(vector.new(0, 0, -1), a:normalize())
+		assert.equal(vector.new(), vector.normalize(vector.new()))
+	end)
+
+	it("floor()", function()
+		local a = vector.new(0.1, 0.9, -0.5)
+		assert.equal(vector.new(0, 0, -1), vector.floor(a))
+		assert.equal(vector.new(0, 0, -1), a:floor())
+	end)
+
+	it("round()", function()
+		local a = vector.new(0.1, 0.9, -0.5)
+		assert.equal(vector.new(0, 1, -1), vector.round(a))
+		assert.equal(vector.new(0, 1, -1), a:round())
+	end)
+
+	it("apply()", function()
+		local i = 0
+		local f = function(x)
+			i = i + 1
+			return x + i
+		end
+		local a = vector.new(0.1, 0.9, -0.5)
+		assert.equal(vector.new(1, 1, 0), vector.apply(a, math.ceil))
+		assert.equal(vector.new(1, 1, 0), a:apply(math.ceil))
+		assert.equal(vector.new(0.1, 0.9, 0.5), vector.apply(a, math.abs))
+		assert.equal(vector.new(0.1, 0.9, 0.5), a:apply(math.abs))
+		assert.equal(vector.new(1.1, 2.9, 2.5), vector.apply(a, f))
+		assert.equal(vector.new(4.1, 5.9, 5.5), a:apply(f))
+	end)
+
+	it("combine()", function()
+		local a = vector.new(1, 2, 3)
+		local b = vector.new(3, 2, 1)
+		assert.equal(vector.add(a, b), vector.combine(a, b, function(x, y) return x + y end))
+		assert.equal(vector.new(3, 2, 3), vector.combine(a, b, math.max))
+		assert.equal(vector.new(1, 2, 1), vector.combine(a, b, math.min))
+	end)
+
+	it("equals()", function()
+		local function assertE(a, b)
+			assert.is_true(vector.equals(a, b))
+		end
+		local function assertNE(a, b)
+			assert.is_false(vector.equals(a, b))
+		end
+
+		assertE({x = 0, y = 0, z = 0}, {x = 0, y = 0, z = 0})
+		assertE({x = -1, y = 0, z = 1}, {x = -1, y = 0, z = 1})
+		assertE({x = -1, y = 0, z = 1}, vector.new(-1, 0, 1))
+		local a = {x = 2, y = 4, z = -10}
+		assertE(a, a)
+		assertNE({x = -1, y = 0, z = 1}, a)
+
+		assert.equal(vector.new(1, 2, 3), vector.new(1, 2, 3))
+		assert.is_true(vector.new(1, 2, 3):equals(vector.new(1, 2, 3)))
+		assert.not_equal(vector.new(1, 2, 3), vector.new(1, 2, 4))
+		assert.is_true(vector.new(1, 2, 3) == vector.new(1, 2, 3))
+		assert.is_false(vector.new(1, 2, 3) == vector.new(1, 3, 3))
+	end)
+
+	it("metatable is same", function()
+		local a = vector.new()
+		local b = vector.new(1, 2, 3)
+
+		assert.equal(true, vector.check(a))
+		assert.equal(true, vector.check(b))
+
+		assert.equal(vector.metatable, getmetatable(a))
+		assert.equal(vector.metatable, getmetatable(b))
+		assert.equal(vector.metatable, a.metatable)
+	end)
+
+	it("sort()", function()
+		local a = vector.new(1, 2, 3)
+		local b = vector.new(0.5, 232, -2)
+		local sorted = {vector.new(0.5, 2, -2), vector.new(1, 232, 3)}
+		assert.same(sorted, {vector.sort(a, b)})
+		assert.same(sorted, {a:sort(b)})
+	end)
+
+	it("angle()", function()
+		assert.equal(math.pi, vector.angle(vector.new(-1, -2, -3), vector.new(1, 2, 3)))
+		assert.equal(math.pi/2, vector.new(0, 1, 0):angle(vector.new(1, 0, 0)))
+	end)
+
+	it("dot()", function()
+		assert.equal(-14, vector.dot(vector.new(-1, -2, -3), vector.new(1, 2, 3)))
+		assert.equal(0, vector.new():dot(vector.new(1, 2, 3)))
+	end)
+
+	it("cross()", function()
+		local a = vector.new(-1, -2, 0)
+		local b = vector.new(1, 2, 3)
+		assert.equal(vector.new(-6, 3, 0), vector.cross(a, b))
+		assert.equal(vector.new(-6, 3, 0), a:cross(b))
+	end)
+
+	it("offset()", function()
+		assert.same({x = 41, y = 52, z = 63}, vector.offset(vector.new(1, 2, 3), 40, 50, 60))
+		assert.equal(vector.new(41, 52, 63), vector.offset(vector.new(1, 2, 3), 40, 50, 60))
+		assert.equal(vector.new(41, 52, 63), vector.new(1, 2, 3):offset(40, 50, 60))
+	end)
+
+	it("is()", function()
+		local some_table1 = {foo = 13, [42] = 1, "bar", 2}
+		local some_table2 = {1, 2, 3}
+		local some_table3 = {x = 1, 2, 3}
+		local some_table4 = {1, 2, z = 3}
+		local old = {x = 1, y = 2, z = 3}
+		local real = vector.new(1, 2, 3)
+
+		assert.is_false(vector.check(nil))
+		assert.is_false(vector.check(1))
+		assert.is_false(vector.check(true))
+		assert.is_false(vector.check("foo"))
+		assert.is_false(vector.check(some_table1))
+		assert.is_false(vector.check(some_table2))
+		assert.is_false(vector.check(some_table3))
+		assert.is_false(vector.check(some_table4))
+		assert.is_false(vector.check(old))
+		assert.is_true(vector.check(real))
+		assert.is_true(real:check())
+	end)
+
+	it("global pairs", function()
+		local out = {}
+		local vec = vector.new(10, 20, 30)
+		for k, v in pairs(vec) do
+			out[k] = v
+		end
+		assert.same({x = 10, y = 20, z = 30}, out)
+	end)
+
+	it("abusing works", function()
+		local v = vector.new(1, 2, 3)
+		v.a = 1
+		assert.equal(1, v.a)
+
+		local a_is_there = false
+		for key, value in pairs(v) do
+			if key == "a" then
+				a_is_there = true
+				assert.equal(value, 1)
+				break
+			end
+		end
+		assert.is_true(a_is_there)
+	end)
+
+	it("add()", function()
+		local a = vector.new(1, 2, 3)
+		local b = vector.new(1, 4, 3)
+		local c = vector.new(2, 6, 6)
+		assert.equal(c, vector.add(a, {x = 1, y = 4, z = 3}))
+		assert.equal(c, vector.add(a, b))
+		assert.equal(c, a:add(b))
+		assert.equal(c, a + b)
+		assert.equal(c, b + a)
+	end)
+
+	it("subtract()", function()
+		local a = vector.new(1, 2, 3)
+		local b = vector.new(2, 4, 3)
+		local c = vector.new(-1, -2, 0)
+		assert.equal(c, vector.subtract(a, {x = 2, y = 4, z = 3}))
+		assert.equal(c, vector.subtract(a, b))
+		assert.equal(c, a:subtract(b))
+		assert.equal(c, a - b)
+		assert.equal(c, -b + a)
+	end)
+
+	it("multiply()", function()
+		local a = vector.new(1, 2, 3)
+		local b = vector.new(2, 4, 3)
+		local c = vector.new(2, 8, 9)
+		local s = 2
+		local d = vector.new(2, 4, 6)
+		assert.equal(c, vector.multiply(a, {x = 2, y = 4, z = 3}))
+		assert.equal(c, vector.multiply(a, b))
+		assert.equal(d, vector.multiply(a, s))
+		assert.equal(d, a:multiply(s))
+		assert.equal(d, a * s)
+		assert.equal(d, s * a)
+		assert.equal(-a, -1 * a)
+	end)
+
+	it("divide()", function()
+		local a = vector.new(1, 2, 3)
+		local b = vector.new(2, 4, 3)
+		local c = vector.new(0.5, 0.5, 1)
+		local s = 2
+		local d = vector.new(0.5, 1, 1.5)
+		assert.equal(c, vector.divide(a, {x = 2, y = 4, z = 3}))
+		assert.equal(c, vector.divide(a, b))
+		assert.equal(d, vector.divide(a, s))
+		assert.equal(d, a:divide(s))
+		assert.equal(d, a / s)
+		assert.equal(d, 1/s * a)
+		assert.equal(-a, a / -1)
+	end)
+
+	it("to_string()", function()
+		local v = vector.new(1, 2, 3.14)
+		assert.same("(1, 2, 3.14)", vector.to_string(v))
+		assert.same("(1, 2, 3.14)", v:to_string())
+		assert.same("(1, 2, 3.14)", tostring(v))
+	end)
+
+	it("from_string()", function()
+		local v = vector.new(1, 2, 3.14)
+		assert.is_true(vector.check(vector.from_string("(1, 2, 3.14)")))
+		assert.same({v, 13}, {vector.from_string("(1, 2, 3.14)")})
+		assert.same({v, 12}, {vector.from_string("(1,2 ,3.14)")})
+		assert.same({v, 12}, {vector.from_string("(1,2,3.14,)")})
+		assert.same({v, 11}, {vector.from_string("(1 2 3.14)")})
+		assert.same({v, 15}, {vector.from_string("( 1, 2, 3.14 )")})
+		assert.same({v, 15}, {vector.from_string(" ( 1, 2, 3.14) ")})
+		assert.same({vector.new(), 8}, {vector.from_string("(0,0,0) ( 1, 2, 3.14) ")})
+		assert.same({v, 22}, {vector.from_string("(0,0,0) ( 1, 2, 3.14) ", 8)})
+		assert.same({v, 22}, {vector.from_string("(0,0,0) ( 1, 2, 3.14) ", 9)})
+		assert.same(nil, vector.from_string("nothing"))
+	end)
+
+	-- This function is needed because of floating point imprecision.
+	local function almost_equal(a, b)
+		if type(a) == "number" then
+			return math.abs(a - b) < 0.00000000001
+		end
+		return vector.distance(a, b) < 0.000000000001
+	end
+
+	describe("rotate_around_axis()", function()
+		it("rotates", function()
+			assert.True(almost_equal({x = -1, y = 0, z = 0},
+				vector.rotate_around_axis({x = 1, y = 0, z = 0}, {x = 0, y = 1, z = 0}, math.pi)))
+			assert.True(almost_equal({x = 0, y = 1, z = 0},
+				vector.rotate_around_axis({x = 0, y = 0, z = 1}, {x = 1, y = 0, z = 0}, math.pi / 2)))
+			assert.True(almost_equal({x = 4, y = 1, z = 1},
+				vector.rotate_around_axis({x = 4, y = 1, z = 1}, {x = 4, y = 1, z = 1}, math.pi / 6)))
+		end)
+		it("keeps distance to axis", function()
+			local rotate1 = {x = 1, y = 3, z = 1}
+			local axis1 = {x = 1, y = 3, z = 2}
+			local rotated1 = vector.rotate_around_axis(rotate1, axis1, math.pi / 13)
+			assert.True(almost_equal(vector.distance(axis1, rotate1), vector.distance(axis1, rotated1)))
+			local rotate2 = {x = 1, y = 1, z = 3}
+			local axis2 = {x = 2, y = 6, z = 100}
+			local rotated2 = vector.rotate_around_axis(rotate2, axis2, math.pi / 23)
+			assert.True(almost_equal(vector.distance(axis2, rotate2), vector.distance(axis2, rotated2)))
+			local rotate3 = {x = 1, y = -1, z = 3}
+			local axis3 = {x = 2, y = 6, z = 100}
+			local rotated3 = vector.rotate_around_axis(rotate3, axis3, math.pi / 2)
+			assert.True(almost_equal(vector.distance(axis3, rotate3), vector.distance(axis3, rotated3)))
+		end)
+		it("rotates back", function()
+			local rotate1 = {x = 1, y = 3, z = 1}
+			local axis1 = {x = 1, y = 3, z = 2}
+			local rotated1 = vector.rotate_around_axis(rotate1, axis1, math.pi / 13)
+			rotated1 = vector.rotate_around_axis(rotated1, axis1, -math.pi / 13)
+			assert.True(almost_equal(rotate1, rotated1))
+			local rotate2 = {x = 1, y = 1, z = 3}
+			local axis2 = {x = 2, y = 6, z = 100}
+			local rotated2 = vector.rotate_around_axis(rotate2, axis2, math.pi / 23)
+			rotated2 = vector.rotate_around_axis(rotated2, axis2, -math.pi / 23)
+			assert.True(almost_equal(rotate2, rotated2))
+			local rotate3 = {x = 1, y = -1, z = 3}
+			local axis3 = {x = 2, y = 6, z = 100}
+			local rotated3 = vector.rotate_around_axis(rotate3, axis3, math.pi / 2)
+			rotated3 = vector.rotate_around_axis(rotated3, axis3, -math.pi / 2)
+			assert.True(almost_equal(rotate3, rotated3))
+		end)
+		it("is right handed", function()
+			local v_before1 = {x = 0, y = 1, z = -1}
+			local v_after1 = vector.rotate_around_axis(v_before1, {x = 1, y = 0, z = 0}, math.pi / 4)
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after1, v_before1)), {x = 1, y = 0, z = 0}))
+
+			local v_before2 = {x = 0, y = 3, z = 4}
+			local v_after2 = vector.rotate_around_axis(v_before2, {x = 1, y = 0, z = 0},  2 * math.pi / 5)
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after2, v_before2)), {x = 1, y = 0, z = 0}))
+
+			local v_before3 = {x = 1, y = 0, z = -1}
+			local v_after3 = vector.rotate_around_axis(v_before3, {x = 0, y = 1, z = 0}, math.pi / 4)
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after3, v_before3)), {x = 0, y = 1, z = 0}))
+
+			local v_before4 = {x = 3, y = 0, z = 4}
+			local v_after4 = vector.rotate_around_axis(v_before4, {x = 0, y = 1, z = 0}, 2 * math.pi / 5)
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after4, v_before4)), {x = 0, y = 1, z = 0}))
+
+			local v_before5 = {x = 1, y = -1, z = 0}
+			local v_after5 = vector.rotate_around_axis(v_before5, {x = 0, y = 0, z = 1}, math.pi / 4)
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after5, v_before5)), {x = 0, y = 0, z = 1}))
+
+			local v_before6 = {x = 3, y = 4, z = 0}
+			local v_after6 = vector.rotate_around_axis(v_before6, {x = 0, y = 0, z = 1}, 2 * math.pi / 5)
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after6, v_before6)), {x = 0, y = 0, z = 1}))
+		end)
+	end)
+
+	describe("rotate()", function()
+		it("rotates", function()
+			assert.True(almost_equal({x = -1, y = 0, z = 0},
+				vector.rotate({x = 1, y = 0, z = 0}, {x = 0, y = math.pi, z = 0})))
+			assert.True(almost_equal({x = 0, y = -1, z = 0},
+				vector.rotate({x = 1, y = 0, z = 0}, {x = 0, y = 0, z = math.pi / 2})))
+			assert.True(almost_equal({x = 1, y = 0, z = 0},
+				vector.rotate({x = 1, y = 0, z = 0}, {x = math.pi / 123, y = 0, z = 0})))
+		end)
+		it("is counterclockwise", function()
+			local v_before1 = {x = 0, y = 1, z = -1}
+			local v_after1 = vector.rotate(v_before1, {x = math.pi / 4, y = 0, z = 0})
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after1, v_before1)), {x = 1, y = 0, z = 0}))
+
+			local v_before2 = {x = 0, y = 3, z = 4}
+			local v_after2 = vector.rotate(v_before2, {x = 2 * math.pi / 5, y = 0, z = 0})
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after2, v_before2)), {x = 1, y = 0, z = 0}))
+
+			local v_before3 = {x = 1, y = 0, z = -1}
+			local v_after3 = vector.rotate(v_before3, {x = 0, y = math.pi / 4, z = 0})
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after3, v_before3)), {x = 0, y = 1, z = 0}))
+
+			local v_before4 = {x = 3, y = 0, z = 4}
+			local v_after4 = vector.rotate(v_before4, {x = 0, y = 2 * math.pi / 5, z = 0})
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after4, v_before4)), {x = 0, y = 1, z = 0}))
+
+			local v_before5 = {x = 1, y = -1, z = 0}
+			local v_after5 = vector.rotate(v_before5, {x = 0, y = 0, z = math.pi / 4})
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after5, v_before5)), {x = 0, y = 0, z = 1}))
+
+			local v_before6 = {x = 3, y = 4, z = 0}
+			local v_after6 = vector.rotate(v_before6, {x = 0, y = 0, z = 2 * math.pi / 5})
+			assert.True(almost_equal(vector.normalize(vector.cross(v_after6, v_before6)), {x = 0, y = 0, z = 1}))
+		end)
+	end)
+
+	it("dir_to_rotation()", function()
+		-- Comparing rotations (pitch, yaw, roll) is hard because of certain ambiguities,
+		-- e.g. (pi, 0, pi) looks exactly the same as (0, pi, 0)
+		-- So instead we convert the rotation back to vectors and compare these.
+		local function forward_at_rot(rot)
+			return vector.rotate(vector.new(0, 0, 1), rot)
+		end
+		local function up_at_rot(rot)
+			return vector.rotate(vector.new(0, 1, 0), rot)
+		end
+		local rot1 = vector.dir_to_rotation({x = 1, y = 0, z = 0}, {x = 0, y = 1, z = 0})
+		assert.True(almost_equal({x = 1, y = 0, z = 0}, forward_at_rot(rot1)))
+		assert.True(almost_equal({x = 0, y = 1, z = 0}, up_at_rot(rot1)))
+		local rot2 = vector.dir_to_rotation({x = 1, y = 1, z = 0}, {x = 0, y = 0, z = 1})
+		assert.True(almost_equal({x = 1/math.sqrt(2), y = 1/math.sqrt(2), z = 0}, forward_at_rot(rot2)))
+		assert.True(almost_equal({x = 0, y = 0, z = 1}, up_at_rot(rot2)))
+		for i = 1, 1000 do
+			local rand_vec = vector.new(math.random(), math.random(), math.random())
+			if vector.length(rand_vec) ~= 0 then
+				local rot_1 = vector.dir_to_rotation(rand_vec)
+				local rot_2 = {
+					x = math.atan2(rand_vec.y, math.sqrt(rand_vec.z * rand_vec.z + rand_vec.x * rand_vec.x)),
+					y = -math.atan2(rand_vec.x, rand_vec.z),
+					z = 0
+				}
+				assert.True(almost_equal(rot_1, rot_2))
+			end
+		end
+
+	end)
+end)