luau/tests/TypeInfer.operators.test.cpp
vegorov-rbx 218159140c
Sync to upstream/release/584 (#977)
* Added support for async typechecking cancellation using a token passed
through frontend options
* Added luaC_enumheap for building debug tools that need a graph of Luau
heap

In our new typechecker:
* Errors or now suppressed when checking property lookup of
error-suppressing unions

In our native code generation (jit):
* Fixed unhandled value type in NOT_ANY lowering
* Fast-call tag checks will exit to VM on failure, instead of relying on
a native fallback
* Added vector type to the type information
* Eliminated redundant direct jumps across dead blocks
* Debugger APIs are now disabled for call frames executing natively
* Implemented support for unwind registration on macOS 14
2023-07-14 11:08:53 -07:00

1260 lines
33 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#include "Luau/AstQuery.h"
#include "Luau/BuiltinDefinitions.h"
#include "Luau/Scope.h"
#include "Luau/TypeInfer.h"
#include "Luau/Type.h"
#include "Luau/VisitType.h"
#include "Fixture.h"
#include "ClassFixture.h"
#include "doctest.h"
using namespace Luau;
LUAU_FASTFLAG(DebugLuauDeferredConstraintResolution)
TEST_SUITE_BEGIN("TypeInferOperators");
TEST_CASE_FIXTURE(Fixture, "or_joins_types")
{
CheckResult result = check(R"(
local s = "a" or 10
local x:string|number = s
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(*requireType("s")), "number | string");
CHECK_EQ(toString(*requireType("x")), "number | string");
}
TEST_CASE_FIXTURE(Fixture, "or_joins_types_with_no_extras")
{
CheckResult result = check(R"(
local s = "a" or 10
local x:number|string = s
local y = x or "s"
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(*requireType("s")), "number | string");
CHECK_EQ(toString(*requireType("y")), "number | string");
}
TEST_CASE_FIXTURE(Fixture, "or_joins_types_with_no_superfluous_union")
{
CheckResult result = check(R"(
local s = "a" or "b"
local x:string = s
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*requireType("s"), *builtinTypes->stringType);
}
TEST_CASE_FIXTURE(Fixture, "and_does_not_always_add_boolean")
{
CheckResult result = check(R"(
local s = "a" and 10
local x:boolean|number = s
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(*requireType("s")), "number");
}
TEST_CASE_FIXTURE(Fixture, "and_adds_boolean_no_superfluous_union")
{
CheckResult result = check(R"(
local s = "a" and true
local x:boolean = s
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*requireType("x"), *builtinTypes->booleanType);
}
TEST_CASE_FIXTURE(Fixture, "and_or_ternary")
{
CheckResult result = check(R"(
local s = (1/2) > 0.5 and "a" or 10
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(*requireType("s")), "number | string");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "primitive_arith_no_metatable")
{
CheckResult result = check(R"(
function add(a: number, b: string)
return a + (tonumber(b) :: number), tostring(a) .. b
end
local n, s = add(2,"3")
)");
LUAU_REQUIRE_NO_ERRORS(result);
const FunctionType* functionType = get<FunctionType>(requireType("add"));
std::optional<TypeId> retType = first(functionType->retTypes);
REQUIRE(retType.has_value());
CHECK_EQ(builtinTypes->numberType, follow(*retType));
CHECK_EQ(requireType("n"), builtinTypes->numberType);
CHECK_EQ(requireType("s"), builtinTypes->stringType);
}
TEST_CASE_FIXTURE(Fixture, "primitive_arith_no_metatable_with_follows")
{
CheckResult result = check(R"(
local PI=3.1415926535897931
local SOLAR_MASS=4*PI * PI
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(requireType("SOLAR_MASS"), builtinTypes->numberType);
}
TEST_CASE_FIXTURE(Fixture, "primitive_arith_possible_metatable")
{
CheckResult result = check(R"(
function add(a: number, b: any)
return a + b
end
local t = add(1,2)
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("any", toString(requireType("t")));
}
TEST_CASE_FIXTURE(Fixture, "some_primitive_binary_ops")
{
CheckResult result = check(R"(
local a = 4 + 8
local b = a + 9
local s = 'hotdogs'
local t = s .. s
local c = b - a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number", toString(requireType("a")));
CHECK_EQ("number", toString(requireType("b")));
CHECK_EQ("string", toString(requireType("s")));
CHECK_EQ("string", toString(requireType("t")));
CHECK_EQ("number", toString(requireType("c")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typecheck_overloaded_multiply_that_is_an_intersection")
{
CheckResult result = check(R"(
--!strict
local Vec3 = {}
Vec3.__index = Vec3
function Vec3.new()
return setmetatable({x=0, y=0, z=0}, Vec3)
end
export type Vec3 = typeof(Vec3.new())
local thefun: any = function(self, o) return self end
local multiply: ((Vec3, Vec3) -> Vec3) & ((Vec3, number) -> Vec3) = thefun
Vec3.__mul = multiply
local a = Vec3.new()
local b = Vec3.new()
local c = a * b
local d = a * 2
local e = a * 'cabbage'
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Vec3", toString(requireType("a")));
CHECK_EQ("Vec3", toString(requireType("b")));
CHECK_EQ("Vec3", toString(requireType("c")));
CHECK_EQ("Vec3", toString(requireType("d")));
CHECK_EQ("Vec3", toString(requireType("e")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typecheck_overloaded_multiply_that_is_an_intersection_on_rhs")
{
CheckResult result = check(R"(
--!strict
local Vec3 = {}
Vec3.__index = Vec3
function Vec3.new()
return setmetatable({x=0, y=0, z=0}, Vec3)
end
export type Vec3 = typeof(Vec3.new())
local thefun: any = function(self, o) return self end
local multiply: ((Vec3, Vec3) -> Vec3) & ((Vec3, number) -> Vec3) = thefun
Vec3.__mul = multiply
local a = Vec3.new()
local b = Vec3.new()
local c = b * a
local d = 2 * a
local e = 'cabbage' * a
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Vec3", toString(requireType("a")));
CHECK_EQ("Vec3", toString(requireType("b")));
CHECK_EQ("Vec3", toString(requireType("c")));
CHECK_EQ("Vec3", toString(requireType("d")));
CHECK_EQ("Vec3", toString(requireType("e")));
}
TEST_CASE_FIXTURE(Fixture, "compare_numbers")
{
CheckResult result = check(R"(
local a = 441
local b = 0
local c = a < b
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "compare_strings")
{
CheckResult result = check(R"(
local a = '441'
local b = '0'
local c = a < b
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cannot_indirectly_compare_types_that_do_not_have_a_metatable")
{
CheckResult result = check(R"(
local a = {}
local b = {}
local c = a < b
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
GenericError* gen = get<GenericError>(result.errors[0]);
REQUIRE(gen != nullptr);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK(gen->message == "Types 'a' and 'b' cannot be compared with < because neither type has a metatable");
else
REQUIRE_EQ(gen->message, "Type a cannot be compared with < because it has no metatable");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "cannot_indirectly_compare_types_that_do_not_offer_overloaded_ordering_operators")
{
CheckResult result = check(R"(
local M = {}
function M.new()
return setmetatable({}, M)
end
type M = typeof(M.new())
local a = M.new()
local b = M.new()
local c = a < b
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
GenericError* gen = get<GenericError>(result.errors[0]);
REQUIRE(gen != nullptr);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK(gen->message == "Types 'M' and 'M' cannot be compared with < because neither type's metatable has a '__lt' metamethod");
else
REQUIRE_EQ(gen->message, "Table M does not offer metamethod __lt");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "cannot_compare_tables_that_do_not_have_the_same_metatable")
{
CheckResult result = check(R"(
--!strict
local M = {}
function M.new()
return setmetatable({}, M)
end
function M.__lt(left, right) return true end
local a = M.new()
local b = {}
local c = a < b -- line 10
local d = b < a -- line 11
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
REQUIRE_EQ((Location{{10, 18}, {10, 23}}), result.errors[0].location);
REQUIRE_EQ((Location{{11, 18}, {11, 23}}), result.errors[1].location);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "produce_the_correct_error_message_when_comparing_a_table_with_a_metatable_with_one_that_does_not")
{
CheckResult result = check(R"(
--!strict
local M = {}
function M.new()
return setmetatable({}, M)
end
function M.__lt(left, right) return true end
type M = typeof(M.new())
local a = M.new()
local b = {}
local c = a < b -- line 10
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
auto err = get<GenericError>(result.errors[0]);
REQUIRE(err != nullptr);
// Frail. :|
REQUIRE_EQ("Types M and b cannot be compared with < because they do not have the same metatable", err->message);
}
TEST_CASE_FIXTURE(Fixture, "in_nonstrict_mode_strip_nil_from_intersections_when_considering_relational_operators")
{
CheckResult result = check(R"(
--!nonstrict
function maybe_a_number(): number?
return 50
end
local a = maybe_a_number() < maybe_a_number()
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "compound_assign_basic")
{
CheckResult result = check(R"(
local s = 10
s += 20
)");
CHECK_EQ(0, result.errors.size());
CHECK_EQ(toString(*requireType("s")), "number");
}
TEST_CASE_FIXTURE(Fixture, "compound_assign_mismatch_op")
{
CheckResult result = check(R"(
local s = 10
s += true
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(result.errors[0], (TypeError{Location{{2, 13}, {2, 17}}, TypeMismatch{builtinTypes->numberType, builtinTypes->booleanType}}));
}
TEST_CASE_FIXTURE(Fixture, "compound_assign_mismatch_result")
{
CheckResult result = check(R"(
local s = 'hello'
s += 10
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(result.errors[0], (TypeError{Location{{2, 8}, {2, 9}}, TypeMismatch{builtinTypes->numberType, builtinTypes->stringType}}));
CHECK_EQ(result.errors[1], (TypeError{Location{{2, 8}, {2, 15}}, TypeMismatch{builtinTypes->stringType, builtinTypes->numberType}}));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "compound_assign_metatable")
{
CheckResult result = check(R"(
--!strict
type V2B = { x: number, y: number }
local v2b: V2B = { x = 0, y = 0 }
local VMT = {}
VMT.__add = function(a: V2, b: V2): V2
return setmetatable({ x = a.x + b.x, y = a.y + b.y }, VMT)
end
type V2 = typeof(setmetatable(v2b, VMT))
local v1: V2 = setmetatable({ x = 1, y = 2 }, VMT)
local v2: V2 = setmetatable({ x = 3, y = 4 }, VMT)
v1 += v2
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "compound_assign_result_must_be_compatible_with_var")
{
CheckResult result = check(R"(
function __add(left, right)
return 123
end
local mt = {
__add = __add,
}
local x = setmetatable({}, mt)
local v: number
v += x -- okay: number + x -> number
x += v -- not okay: x </: number
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK(result.errors[0] == TypeError{Location{{13, 8}, {13, 14}}, TypeMismatch{requireType("x"), builtinTypes->numberType}});
}
TEST_CASE_FIXTURE(BuiltinsFixture, "compound_assign_mismatch_metatable")
{
CheckResult result = check(R"(
--!strict
type V2B = { x: number, y: number }
local v2b: V2B = { x = 0, y = 0 }
local VMT = {}
type V2 = typeof(setmetatable(v2b, VMT))
function VMT.__mod(a: V2, b: V2): number
return a.x * b.x + a.y * b.y
end
local v1: V2 = setmetatable({ x = 1, y = 2 }, VMT)
local v2: V2 = setmetatable({ x = 3, y = 4 }, VMT)
v1 %= v2
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK("Type 'number' could not be converted into 'V2'" == toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "CallOrOfFunctions")
{
CheckResult result = check(R"(
function f() return 1; end
function g() return 2; end
(f or g)()
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "CallAndOrOfFunctions")
{
CheckResult result = check(R"(
function f() return 1; end
function g() return 2; end
local x = false
(x and f or g)()
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typecheck_unary_minus")
{
CheckResult result = check(R"(
--!strict
local foo
local mt = {}
mt.__unm = function(val): string
return tostring(val.value) .. "test"
end
foo = setmetatable({
value = 10
}, mt)
local a = -foo
local b = 1+-1
local bar = {
value = 10
}
local c = -bar -- disallowed
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("string", toString(requireType("a")));
CHECK_EQ("number", toString(requireType("b")));
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK(toString(result.errors[0]) == "Type 'bar' could not be converted into 'number'");
}
else
{
GenericError* gen = get<GenericError>(result.errors[0]);
REQUIRE(gen);
REQUIRE_EQ(gen->message, "Unary operator '-' not supported by type 'bar'");
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typecheck_unary_minus_error")
{
CheckResult result = check(R"(
--!strict
local mt = {}
mt.__unm = function(val: boolean): string
return "test"
end
local foo = setmetatable({
value = 10
}, mt)
local a = -foo
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("string", toString(requireType("a")));
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE_EQ(*tm->wantedType, *builtinTypes->booleanType);
// given type is the typeof(foo) which is complex to compare against
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typecheck_unary_len_error")
{
CheckResult result = check(R"(
--!strict
local mt = {}
mt.__len = function(val): string
return "test"
end
local foo = setmetatable({
value = 10,
}, mt)
local a = #foo
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("number", toString(requireType("a")));
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE_EQ(*tm->wantedType, *builtinTypes->numberType);
REQUIRE_EQ(*tm->givenType, *builtinTypes->stringType);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "unary_not_is_boolean")
{
CheckResult result = check(R"(
local b = not "string"
local c = not (math.random() > 0.5 and "string" or 7)
)");
LUAU_REQUIRE_NO_ERRORS(result);
REQUIRE_EQ("boolean", toString(requireType("b")));
REQUIRE_EQ("boolean", toString(requireType("c")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "disallow_string_and_types_without_metatables_from_arithmetic_binary_ops")
{
CheckResult result = check(R"(
--!strict
local a = "1.24" + 123 -- not allowed
local foo = {
value = 10
}
local b = foo + 1 -- not allowed
local bar = {
value = 1
}
local mt = {}
setmetatable(bar, mt)
mt.__add = function(a: typeof(bar), b: number): number
return a.value + b
end
local c = bar + 1 -- allowed
local d = bar + foo -- not allowed
)");
LUAU_REQUIRE_ERROR_COUNT(3, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK_EQ(*tm->wantedType, *builtinTypes->numberType);
CHECK_EQ(*tm->givenType, *builtinTypes->stringType);
GenericError* gen1 = get<GenericError>(result.errors[1]);
REQUIRE(gen1);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ(gen1->message, "Operator + is not applicable for '{ value: number }' and 'number' because neither type has a metatable");
else
CHECK_EQ(gen1->message, "Binary operator '+' not supported by types 'foo' and 'number'");
TypeMismatch* tm2 = get<TypeMismatch>(result.errors[2]);
REQUIRE(tm2);
CHECK_EQ(*tm2->wantedType, *builtinTypes->numberType);
CHECK_EQ(*tm2->givenType, *requireType("foo"));
}
// CLI-29033
TEST_CASE_FIXTURE(Fixture, "unknown_type_in_comparison")
{
CheckResult result = check(R"(
function merge(lower, greater)
if lower.y == greater.y then
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "concat_op_on_free_lhs_and_string_rhs")
{
CheckResult result = check(R"(
local function f(x)
return x .. "y"
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
REQUIRE(get<CannotInferBinaryOperation>(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "concat_op_on_string_lhs_and_free_rhs")
{
CheckResult result = check(R"(
local function f(x)
return "foo" .. x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(string) -> string", toString(requireType("f")));
}
TEST_CASE_FIXTURE(Fixture, "strict_binary_op_where_lhs_unknown")
{
std::vector<std::string> ops = {"+", "-", "*", "/", "%", "^", ".."};
std::string src = "function foo(a, b)\n";
for (const auto& op : ops)
src += "local _ = a " + op + " b\n";
src += "end";
CheckResult result = check(src);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
LUAU_REQUIRE_ERROR_COUNT(ops.size(), result);
CHECK_EQ("Type family instance Add<a, b> depends on generic function parameters but does not appear in the function signature; this "
"construct cannot be type-checked at this time",
toString(result.errors[0]));
CHECK_EQ("Unknown type used in - operation; consider adding a type annotation to 'a'", toString(result.errors[1]));
}
else
{
LUAU_REQUIRE_ERROR_COUNT(ops.size(), result);
CHECK_EQ("Unknown type used in + operation; consider adding a type annotation to 'a'", toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "and_binexps_dont_unify")
{
CheckResult result = check(R"(
--!strict
local t = {}
while true and t[1] do
print(t[1].test)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "error_on_invalid_operand_types_to_relational_operators")
{
CheckResult result = check(R"(
local a: boolean = true
local b: boolean = false
local foo = a < b
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
GenericError* ge = get<GenericError>(result.errors[0]);
REQUIRE(ge);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("Types 'boolean' and 'boolean' cannot be compared with relational operator <", ge->message);
else
CHECK_EQ("Type 'boolean' cannot be compared with relational operator <", ge->message);
}
TEST_CASE_FIXTURE(Fixture, "error_on_invalid_operand_types_to_relational_operators2")
{
CheckResult result = check(R"(
local a: number | string = ""
local b: number | string = 1
local foo = a < b
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
GenericError* ge = get<GenericError>(result.errors[0]);
REQUIRE(ge);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("Types 'number | string' and 'number | string' cannot be compared with relational operator <", ge->message);
else
CHECK_EQ("Type 'number | string' cannot be compared with relational operator <", ge->message);
}
TEST_CASE_FIXTURE(Fixture, "cli_38355_recursive_union")
{
ScopedFastFlag sff{"LuauOccursIsntAlwaysFailure", true};
CheckResult result = check(R"(
--!strict
local _
_ += _ and _ or _ and _ or _ and _
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Unknown type used in + operation; consider adding a type annotation to '_'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "UnknownGlobalCompoundAssign")
{
// In non-strict mode, global definition is still allowed
{
CheckResult result = check(R"(
--!nonstrict
a = a + 1
print(a)
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(toString(result.errors[0]), "Unknown global 'a'");
}
// In strict mode we no longer generate two errors from lhs
{
CheckResult result = check(R"(
--!strict
a += 1
print(a)
)");
LUAU_REQUIRE_ERRORS(result);
CHECK_EQ(toString(result.errors[0]), "Unknown global 'a'");
}
// In non-strict mode, compound assignment is not a definition, it's a modification
{
CheckResult result = check(R"(
--!nonstrict
a += 1
print(a)
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(toString(result.errors[0]), "Unknown global 'a'");
}
}
TEST_CASE_FIXTURE(Fixture, "strip_nil_from_lhs_or_operator")
{
CheckResult result = check(R"(
--!strict
local a: number? = nil
local b: number = a or 1
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "strip_nil_from_lhs_or_operator2")
{
CheckResult result = check(R"(
--!nonstrict
local a: number? = nil
local b: number = a or 1
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "dont_strip_nil_from_rhs_or_operator")
{
CheckResult result = check(R"(
--!strict
local a: number? = nil
local b: number = 1 or a
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK_EQ(builtinTypes->numberType, tm->wantedType);
CHECK_EQ("number?", toString(tm->givenType));
}
TEST_CASE_FIXTURE(Fixture, "operator_eq_verifies_types_do_intersect")
{
CheckResult result = check(R"(
type Array<T> = { [number]: T }
type Fiber = { id: number }
type null = {}
local fiberStack: Array<Fiber | null> = {}
local index = 0
local function f(fiber: Fiber)
local a = fiber ~= fiberStack[index]
local b = fiberStack[index] ~= fiber
end
return f
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "operator_eq_operands_are_not_subtypes_of_each_other_but_has_overlap")
{
CheckResult result = check(R"(
local function f(a: string | number, b: boolean | number)
return a == b
end
)");
// This doesn't produce any errors but for the wrong reasons.
// This unit test serves as a reminder to not try and unify the operands on `==`/`~=`.
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "operator_eq_completely_incompatible")
{
CheckResult result = check(R"(
local a: string | number = "hi"
local b: {x: string}? = {x = "bye"}
local r1 = a == b
local r2 = b == a
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
}
TEST_CASE_FIXTURE(Fixture, "refine_and_or")
{
CheckResult result = check(R"(
local t: {x: number?}? = {x = nil}
local u = t and t.x or 5
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number", toString(requireType("u")));
}
TEST_CASE_FIXTURE(Fixture, "infer_any_in_all_modes_when_lhs_is_unknown")
{
CheckResult result = check(Mode::Strict, R"(
local function f(x, y)
return x + y
end
)");
if (FFlag::DebugLuauDeferredConstraintResolution)
{
LUAU_REQUIRE_NO_ERRORS(result);
CHECK(toString(requireType("f")) == "<a, b>(a, b) -> Add<a, b>");
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(toString(result.errors[0]), "Unknown type used in + operation; consider adding a type annotation to 'x'");
}
result = check(Mode::Nonstrict, R"(
local function f(x, y)
return x + y
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
// When type inference is unified, we could add an assertion that
// the strict and nonstrict types are equivalent. This isn't actually
// the case right now, though.
}
TEST_CASE_FIXTURE(BuiltinsFixture, "equality_operations_succeed_if_any_union_branch_succeeds")
{
CheckResult result = check(R"(
local mm = {}
type Foo = typeof(setmetatable({}, mm))
local x: Foo
local y: Foo?
local v1 = x == y
local v2 = y == x
local v3 = x ~= y
local v4 = y ~= x
)");
LUAU_REQUIRE_NO_ERRORS(result);
CheckResult result2 = check(R"(
local mm1 = {
x = "foo",
}
local mm2 = {
y = "bar",
}
type Foo = typeof(setmetatable({}, mm1))
type Bar = typeof(setmetatable({}, mm2))
local x1: Foo
local x2: Foo?
local y1: Bar
local y2: Bar?
local v1 = x1 == y1
local v2 = x2 == y2
)");
LUAU_REQUIRE_ERROR_COUNT(1, result2);
CHECK(toString(result2.errors[0]) == "Types Foo and Bar cannot be compared with == because they do not have the same metatable");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "expected_types_through_binary_and")
{
CheckResult result = check(R"(
local x: "a" | "b" | boolean = math.random() > 0.5 and "a"
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "expected_types_through_binary_or")
{
CheckResult result = check(R"(
local x: "a" | "b" | boolean = math.random() > 0.5 or "b"
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(ClassFixture, "unrelated_classes_cannot_be_compared")
{
CheckResult result = check(R"(
local a = BaseClass.New()
local b = UnrelatedClass.New()
local c = a == b
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "unrelated_primitives_cannot_be_compared")
{
CheckResult result = check(R"(
local c = 5 == true
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "mm_comparisons_must_return_a_boolean")
{
if (!FFlag::DebugLuauDeferredConstraintResolution)
return;
CheckResult result = check(R"(
local mm1 = {
__lt = function(self, other)
return 123
end,
}
local mm2 = {
__lt = function(self, other)
return
end,
}
local o1 = setmetatable({}, mm1)
local v1 = o1 < o1
local o2 = setmetatable({}, mm2)
local v2 = o2 < o2
)");
LUAU_REQUIRE_ERROR_COUNT(4, result);
CHECK(requireType("v1") == builtinTypes->booleanType);
CHECK(requireType("v2") == builtinTypes->booleanType);
CHECK(toString(result.errors[1]) == "Metamethod '__lt' must return a boolean");
CHECK(toString(result.errors[3]) == "Metamethod '__lt' must return a boolean");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "reworked_and")
{
CheckResult result = check(R"(
local a: number? = 5
local b: boolean = (a or 1) > 10
local c -- free
local x = a and 1
local y = 'a' and 1
local z = b and 1
local w = c and 1
)");
CHECK("number?" == toString(requireType("x")));
CHECK("number" == toString(requireType("y")));
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK("false | number" == toString(requireType("z")));
else
CHECK("boolean | number" == toString(requireType("z"))); // 'false' widened to boolean
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK("((false?) & a) | number" == toString(requireType("w")));
else
CHECK("(boolean | number)?" == toString(requireType("w")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "reworked_or")
{
CheckResult result = check(R"(
local a: number | false = 5
local b: number? = 6
local c: boolean = true
local d: true = true
local e: false = false
local f: nil = false
local a1 = a or 'a'
local b1 = b or 4
local c1 = c or 'c'
local d1 = d or 'd'
local e1 = e or 'e'
local f1 = f or 'f'
)");
CHECK("number | string" == toString(requireType("a1")));
CHECK("number" == toString(requireType("b1")));
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK("string | true" == toString(requireType("c1")));
CHECK("string | true" == toString(requireType("d1")));
}
else
{
CHECK("boolean | string" == toString(requireType("c1"))); // 'true' widened to boolean
CHECK("boolean | string" == toString(requireType("d1"))); // 'true' widened to boolean
}
CHECK("string" == toString(requireType("e1")));
CHECK("string" == toString(requireType("f1")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "reducing_and")
{
CheckResult result = check(R"(
type Foo = { name: string?, flag: boolean? }
local arr: {Foo} = {}
local function foo(arg: {name: string}?)
local name = if arg and arg.name then arg.name else nil
table.insert(arr, {
name = name or "",
flag = name ~= nil and name ~= "",
})
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau_polyfill_is_array_simplified")
{
CheckResult result = check(R"(
--!strict
return function(value: any) : boolean
if typeof(value) ~= "number" then
return false
end
if value % 1 ~= 0 or value < 1 then
return false
end
return true
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau_polyfill_is_array")
{
CheckResult result = check(R"(
--!strict
return function(value: any): boolean
if typeof(value) ~= "table" then
return false
end
if next(value) == nil then
-- an empty table is an empty array
return true
end
local length = #value
if length == 0 then
return false
end
local count = 0
local sum = 0
for key in pairs(value) do
if typeof(key) ~= "number" then
return false
end
if key % 1 ~= 0 or key < 1 then
return false
end
count += 1
sum += key
end
return sum == (count * (count + 1) / 2)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau-polyfill.String.slice")
{
CheckResult result = check(R"(
--!strict
local function slice(str: string, startIndexStr: string | number, lastIndexStr: (string | number)?): string
local strLen, invalidBytePosition = utf8.len(str)
assert(strLen ~= nil, ("string `%s` has an invalid byte at position %s"):format(str, tostring(invalidBytePosition)))
local startIndex = tonumber(startIndexStr)
-- if no last index length set, go to str length + 1
local lastIndex = strLen + 1
assert(typeof(lastIndex) == "number", "lastIndexStr should convert to number")
if lastIndex > strLen then
lastIndex = strLen + 1
end
local startIndexByte = utf8.offset(str, startIndex)
return string.sub(str, startIndexByte, startIndexByte)
end
return slice
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau-polyfill.Array.startswith")
{
// This test also exercises whether the binary operator == passes the correct expected type
// to it's l,r operands
CheckResult result = check(R"(
--!strict
local function startsWith(value: string, substring: string, position: number?): boolean
-- Luau FIXME: we have to use a tmp variable, as Luau doesn't understand the logic below narrow position to `number`
local position_
if position == nil or position < 1 then
position_ = 1
else
position_ = position
end
return value:find(substring, position_, true) == position_
end
return startsWith
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "add_type_family_works")
{
if (!FFlag::DebugLuauDeferredConstraintResolution)
return;
CheckResult result = check(R"(
local function add(x, y)
return x + y
end
local a = add(1, 2)
local b = add("foo", "bar")
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK(toString(requireType("a")) == "number");
CHECK(toString(requireType("b")) == "Add<string, string>");
CHECK(toString(result.errors[0]) == "Type family instance Add<string, string> is uninhabited");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "normalize_strings_comparison")
{
CheckResult result = check(R"(
local function sortKeysForPrinting(a: any, b)
local typeofA = type(a)
local typeofB = type(b)
-- strings and numbers are sorted numerically/alphabetically
if typeofA == typeofB and (typeofA == "number" or typeofA == "string") then
return a < b
end
-- sort the rest by type name
return typeofA < typeofB
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_SUITE_END();