luau/tests/TypeInfer.refinements.test.cpp
ariel 640ebbc0a5
Sync to upstream/release/663 (#1699)
Hey folks, another week means another Luau release! This one features a
number of bug fixes in the New Type Solver including improvements to
user-defined type functions and a bunch of work to untangle some of the
outstanding issues we've been seeing with constraint solving not
completing in real world use. We're also continuing to make progress on
crashes and other problems that affect the stability of fragment
autocomplete, as we work towards delivering consistent, low-latency
autocomplete for any editor environment.

## New Type Solver

- Fix a bug in user-defined type functions where `print` would
incorrectly insert `\1` a number of times.
- Fix a bug where attempting to refine an optional generic with a type
test will cause a false positive type error (fixes #1666)
- Fix a bug where the `refine` type family would not skip over
`*no-refine*` discriminants (partial resolution for #1424)
- Fix a constraint solving bug where recursive function calls would
consistently produce cyclic constraints leading to incomplete or
inaccurate type inference.
- Implement `readparent` and `writeparent` for class types in
user-defined type functions, replacing the incorrectly included `parent`
method.
- Add initial groundwork (under a debug flag) for eager free type
generalization, moving us towards further improvements to constraint
solving incomplete errors.

## Fragment Autocomplete

- Ease up some assertions to improve stability of mixed-mode use of the
two type solvers (i.e. using Fragment Autocomplete on a type graph
originally produced by the old type solver)
- Resolve a bug with type compatibility checks causing internal compiler
errors in autocomplete.

## Lexer and Parser

- Improve the accuracy of the roundtrippable AST parsing mode by
correctly placing closing parentheses on type groupings.
- Add a getter for `offset` in the Lexer by @aduermael in #1688
- Add a second entry point to the parser to parse an expression,
`parseExpr`

## Internal Contributors

Co-authored-by: Andy Friesen <afriesen@roblox.com>
Co-authored-by: Ariel Weiss <aaronweiss@roblox.com>
Co-authored-by: Aviral Goel <agoel@roblox.com>
Co-authored-by: Hunter Goldstein <hgoldstein@roblox.com>
Co-authored-by: James McNellis <jmcnellis@roblox.com>
Co-authored-by: Talha Pathan <tpathan@roblox.com>
Co-authored-by: Vighnesh Vijay <vvijay@roblox.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>

---------

Co-authored-by: Hunter Goldstein <hgoldstein@roblox.com>
Co-authored-by: Varun Saini <61795485+vrn-sn@users.noreply.github.com>
Co-authored-by: Alexander Youngblood <ayoungblood@roblox.com>
Co-authored-by: Menarul Alam <malam@roblox.com>
Co-authored-by: Aviral Goel <agoel@roblox.com>
Co-authored-by: Vighnesh <vvijay@roblox.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>
2025-02-28 14:42:30 -08:00

2529 lines
74 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#include "Luau/Normalize.h"
#include "Luau/Scope.h"
#include "Luau/TypeInfer.h"
#include "Fixture.h"
#include "doctest.h"
LUAU_FASTFLAG(LuauSolverV2)
LUAU_FASTFLAG(DebugLuauEqSatSimplification)
LUAU_FASTFLAG(LuauGeneralizationRemoveRecursiveUpperBound2)
LUAU_FASTFLAG(LuauIntersectNotNil)
LUAU_FASTFLAG(LuauSkipNoRefineDuringRefinement)
using namespace Luau;
namespace
{
struct MagicInstanceIsA final : MagicFunction
{
std::optional<WithPredicate<TypePackId>> handleOldSolver(
TypeChecker& typeChecker,
const ScopePtr& scope,
const AstExprCall& expr,
WithPredicate<TypePackId> withPredicate
) override
{
if (expr.args.size != 1)
return std::nullopt;
auto index = expr.func->as<Luau::AstExprIndexName>();
auto str = expr.args.data[0]->as<Luau::AstExprConstantString>();
if (!index || !str)
return std::nullopt;
std::optional<LValue> lvalue = tryGetLValue(*index->expr);
std::optional<TypeFun> tfun = scope->lookupType(std::string(str->value.data, str->value.size));
if (!lvalue || !tfun)
return std::nullopt;
ModulePtr module = typeChecker.currentModule;
TypePackId booleanPack = module->internalTypes.addTypePack({typeChecker.booleanType});
return WithPredicate<TypePackId>{booleanPack, {IsAPredicate{std::move(*lvalue), expr.location, tfun->type}}};
}
bool infer(const MagicFunctionCallContext&) override
{
return false;
}
void refine(const MagicRefinementContext& ctx) override
{
if (ctx.callSite->args.size != 1 || ctx.discriminantTypes.empty())
return;
auto index = ctx.callSite->func->as<Luau::AstExprIndexName>();
auto str = ctx.callSite->args.data[0]->as<Luau::AstExprConstantString>();
if (!index || !str)
return;
std::optional<TypeId> discriminantTy = ctx.discriminantTypes[0];
if (!discriminantTy)
return;
std::optional<TypeFun> tfun = ctx.scope->lookupType(std::string(str->value.data, str->value.size));
if (!tfun)
return;
LUAU_ASSERT(get<BlockedType>(*discriminantTy));
asMutable(*discriminantTy)->ty.emplace<BoundType>(tfun->type);
}
};
struct RefinementClassFixture : BuiltinsFixture
{
RefinementClassFixture()
{
TypeArena& arena = frontend.globals.globalTypes;
NotNull<Scope> scope{frontend.globals.globalScope.get()};
std::optional<TypeId> rootSuper = std::make_optional(builtinTypes->classType);
unfreeze(arena);
TypeId vec3 = arena.addType(ClassType{"Vector3", {}, rootSuper, std::nullopt, {}, nullptr, "Test", {}});
getMutable<ClassType>(vec3)->props = {
{"X", Property{builtinTypes->numberType}},
{"Y", Property{builtinTypes->numberType}},
{"Z", Property{builtinTypes->numberType}},
};
TypeId inst = arena.addType(ClassType{"Instance", {}, rootSuper, std::nullopt, {}, nullptr, "Test", {}});
TypePackId isAParams = arena.addTypePack({inst, builtinTypes->stringType});
TypePackId isARets = arena.addTypePack({builtinTypes->booleanType});
TypeId isA = arena.addType(FunctionType{isAParams, isARets});
getMutable<FunctionType>(isA)->magic = std::make_shared<MagicInstanceIsA>();
getMutable<ClassType>(inst)->props = {
{"Name", Property{builtinTypes->stringType}},
{"IsA", Property{isA}},
};
TypeId folder = frontend.globals.globalTypes.addType(ClassType{"Folder", {}, inst, std::nullopt, {}, nullptr, "Test", {}});
TypeId part = frontend.globals.globalTypes.addType(ClassType{"Part", {}, inst, std::nullopt, {}, nullptr, "Test", {}});
getMutable<ClassType>(part)->props = {
{"Position", Property{vec3}},
};
frontend.globals.globalScope->exportedTypeBindings["Vector3"] = TypeFun{{}, vec3};
frontend.globals.globalScope->exportedTypeBindings["Instance"] = TypeFun{{}, inst};
frontend.globals.globalScope->exportedTypeBindings["Folder"] = TypeFun{{}, folder};
frontend.globals.globalScope->exportedTypeBindings["Part"] = TypeFun{{}, part};
for (const auto& [name, ty] : frontend.globals.globalScope->exportedTypeBindings)
persist(ty.type);
freeze(frontend.globals.globalTypes);
}
};
} // namespace
TEST_SUITE_BEGIN("RefinementTest");
TEST_CASE_FIXTURE(Fixture, "is_truthy_constraint")
{
CheckResult result = check(R"(
function f(v: string?)
if v then
local s = v
else
local s = v
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("nil", toString(requireTypeAtPosition({5, 26})));
}
TEST_CASE_FIXTURE(Fixture, "invert_is_truthy_constraint")
{
CheckResult result = check(R"(
function f(v: string?)
if not v then
local s = v
else
local s = v
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("string", toString(requireTypeAtPosition({5, 26})));
}
TEST_CASE_FIXTURE(Fixture, "parenthesized_expressions_are_followed_through")
{
CheckResult result = check(R"(
function f(v: string?)
if (not v) then
local s = v
else
local s = v
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("string", toString(requireTypeAtPosition({5, 26})));
}
TEST_CASE_FIXTURE(Fixture, "and_constraint")
{
CheckResult result = check(R"(
function f(a: string?, b: number?)
if a and b then
local x = a
local y = b
else
local x = a
local y = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("number", toString(requireTypeAtPosition({4, 26})));
CHECK_EQ("string?", toString(requireTypeAtPosition({6, 26})));
CHECK_EQ("number?", toString(requireTypeAtPosition({7, 26})));
}
TEST_CASE_FIXTURE(Fixture, "not_and_constraint")
{
CheckResult result = check(R"(
function f(a: string?, b: number?)
if not (a and b) then
local x = a
local y = b
else
local x = a
local y = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string?", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("number?", toString(requireTypeAtPosition({4, 26})));
CHECK_EQ("string", toString(requireTypeAtPosition({6, 26})));
CHECK_EQ("number", toString(requireTypeAtPosition({7, 26})));
}
TEST_CASE_FIXTURE(Fixture, "or_predicate_with_truthy_predicates")
{
CheckResult result = check(R"(
function f(a: string?, b: number?)
if a or b then
local x = a
local y = b
else
local x = a
local y = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string?", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("number?", toString(requireTypeAtPosition({4, 26})));
CHECK_EQ("nil", toString(requireTypeAtPosition({6, 26})));
CHECK_EQ("nil", toString(requireTypeAtPosition({7, 26})));
}
TEST_CASE_FIXTURE(Fixture, "a_and_b_or_a_and_c")
{
CheckResult result = check(R"(
function f(a: string?, b: number?, c: boolean)
if (a and b) or (a and c) then
local foo = a
local bar = b
local baz = c
else
local foo = a
local bar = b
local baz = c
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number?", toString(requireTypeAtPosition({4, 28})));
if (FFlag::LuauSolverV2)
CHECK_EQ("boolean", toString(requireTypeAtPosition({5, 28})));
else
CHECK_EQ("true", toString(requireTypeAtPosition({5, 28}))); // oh no! :(
CHECK_EQ("string?", toString(requireTypeAtPosition({7, 28})));
CHECK_EQ("number?", toString(requireTypeAtPosition({8, 28})));
CHECK_EQ("boolean", toString(requireTypeAtPosition({9, 28})));
}
TEST_CASE_FIXTURE(Fixture, "type_assertion_expr_carry_its_constraints")
{
CheckResult result = check(R"(
function g(a: number?, b: string?)
if (a :: any) and (b :: any) then
local x = a
local y = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ("number?", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("string?", toString(requireTypeAtPosition({4, 26})));
}
else
{
// We're going to drop support for type refinements through type assertions.
CHECK_EQ("number", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("string", toString(requireTypeAtPosition({4, 26})));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typeguard_in_if_condition_position")
{
CheckResult result = check(R"(
function f(s: any, t: unknown)
if type(s) == "number" then
local n = s
end
if type(t) == "number" then
local n = t
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
// DCR changes refinements to preserve error suppression.
if (FFlag::LuauSolverV2)
CHECK_EQ("*error-type* | number", toString(requireTypeAtPosition({3, 26})));
else
CHECK_EQ("number", toString(requireTypeAtPosition({3, 26})));
CHECK_EQ("number", toString(requireTypeAtPosition({6, 26})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typeguard_in_assert_position")
{
CheckResult result = check(R"(
function f(a)
assert(type(a) == "number")
local b = a
return b
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK("<a>(a) -> a & number" == toString(requireType("f")));
else
CHECK("<a>(a) -> number" == toString(requireType("f")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknown_to_table_then_test_a_prop")
{
CheckResult result = check(R"(
local function f(x: unknown): string?
if typeof(x) == "table" then
if typeof(x.foo) == "string" then
return x.foo
end
end
return nil
end
)");
if (FFlag::LuauSolverV2)
LUAU_REQUIRE_NO_ERRORS(result);
else
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
for (size_t i = 0; i < result.errors.size(); i++)
{
const UnknownProperty* up = get<UnknownProperty>(result.errors[i]);
REQUIRE_EQ("foo", up->key);
REQUIRE_EQ("unknown", toString(up->table));
}
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknown_to_table_then_test_a_nested_prop")
{
CheckResult result = check(R"(
local function f(x: unknown): string?
if typeof(x) == "table" then
-- this should error, `x.foo` is an unknown property
if typeof(x.foo.bar) == "string" then
return x.foo.bar
end
end
return nil
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const UnknownProperty* up = get<UnknownProperty>(result.errors[0]);
REQUIRE_EQ("bar", up->key);
REQUIRE_EQ("unknown", toString(up->table));
}
else
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
for (size_t i = 0; i < result.errors.size(); i++)
{
const UnknownProperty* up = get<UnknownProperty>(result.errors[i]);
REQUIRE_EQ("foo", up->key);
REQUIRE_EQ("unknown", toString(up->table));
}
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknown_to_table_then_test_a_tested_nested_prop")
{
CheckResult result = check(R"(
local function f(x: unknown): string?
if typeof(x) == "table" then
if typeof(x.foo) == "table" and typeof(x.foo.bar) == "string" then
return x.foo.bar
end
end
return nil
end
)");
if (FFlag::LuauSolverV2)
LUAU_REQUIRE_NO_ERRORS(result);
else
{
LUAU_REQUIRE_ERROR_COUNT(3, result);
for (size_t i = 0; i < result.errors.size(); i++)
{
const UnknownProperty* up = get<UnknownProperty>(result.errors[i]);
REQUIRE_EQ("foo", up->key);
REQUIRE_EQ("unknown", toString(up->table));
}
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "call_an_incompatible_function_after_using_typeguard")
{
CheckResult result = check(R"(
local function f(x: number)
return x
end
local function g(x: unknown)
if type(x) == "string" then
f(x)
end
end
local function h(x: any)
if type(x) == "string" then
f(x)
end
end
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK("Type 'string' could not be converted into 'number'" == toString(result.errors[0]));
CHECK(Location{{7, 18}, {7, 19}} == result.errors[0].location);
CHECK("Type 'string' could not be converted into 'number'" == toString(result.errors[1]));
CHECK(Location{{13, 18}, {13, 19}} == result.errors[1].location);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "impossible_type_narrow_is_not_an_error")
{
// This unit test serves as a reminder to not implement this warning until Luau is intelligent enough.
// For instance, getting a value out of the indexer and checking whether the value exists is not an error.
CheckResult result = check(R"(
local t: {string} = {"a", "b", "c"}
local v = t[4]
if not v then
t[4] = "d"
else
print(v)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "truthy_constraint_on_properties")
{
CheckResult result = check(R"(
local t: {x: number?} = {x = 1}
if t.x then
local t2 = t
local foo = t.x
end
local bar = t.x
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
if (FFlag::DebugLuauEqSatSimplification)
{
CHECK("{ x: number }" == toString(requireTypeAtPosition({4, 23})));
}
else
{
// CLI-115281 - Types produced by refinements don't always get simplified
CHECK("{ x: number? } & { x: ~(false?) }" == toString(requireTypeAtPosition({4, 23})));
}
CHECK("number" == toString(requireTypeAtPosition({5, 26})));
}
CHECK_EQ("number?", toString(requireType("bar")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "index_on_a_refined_property")
{
CheckResult result = check(R"(
local t: {x: {y: string}?} = {x = {y = "hello!"}}
if t.x then
print(t.x.y)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "assert_non_binary_expressions_actually_resolve_constraints")
{
CheckResult result = check(R"(
local foo: string? = "hello"
assert(foo)
local bar: string = foo
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "lvalue_is_equal_to_another_lvalue")
{
CheckResult result = check(R"(
local function f(a: (string | number)?, b: boolean?)
if a == b then
local foo, bar = a, b
else
local foo, bar = a, b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(requireTypeAtPosition({3, 33})), "(number | string)?"); // a == b
CHECK_EQ(toString(requireTypeAtPosition({3, 36})), "boolean?"); // a == b
CHECK_EQ(toString(requireTypeAtPosition({5, 33})), "(number | string)?"); // a ~= b
CHECK_EQ(toString(requireTypeAtPosition({5, 36})), "boolean?"); // a ~= b
}
TEST_CASE_FIXTURE(Fixture, "lvalue_is_equal_to_a_term")
{
CheckResult result = check(R"(
local function f(a: (string | number)?)
if a == 1 then
local foo = a
else
local foo = a
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(requireTypeAtPosition({3, 28})), "(number | string)?"); // a == 1;
CHECK_EQ(toString(requireTypeAtPosition({5, 28})), "(number | string)?"); // a ~= 1
}
TEST_CASE_FIXTURE(Fixture, "term_is_equal_to_an_lvalue")
{
CheckResult result = check(R"(
local function f(a: (string | number)?)
if "hello" == a then
local foo = a
else
local foo = a
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ(toString(requireTypeAtPosition({3, 28})), R"("hello")"); // a == "hello"
CHECK_EQ(toString(requireTypeAtPosition({5, 28})), R"(((string & ~"hello") | number)?)"); // a ~= "hello"
}
else
{
CHECK_EQ(toString(requireTypeAtPosition({3, 28})), R"("hello")"); // a == "hello"
CHECK_EQ(toString(requireTypeAtPosition({5, 28})), R"((number | string)?)"); // a ~= "hello"
}
}
TEST_CASE_FIXTURE(Fixture, "lvalue_is_not_nil")
{
CheckResult result = check(R"(
local function f(a: (string | number)?)
if a ~= nil then
local foo = a
else
local foo = a
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(requireTypeAtPosition({3, 28})), "number | string"); // a ~= nil
if (FFlag::LuauSolverV2)
CHECK_EQ(toString(requireTypeAtPosition({5, 28})), "nil"); // a == nil :)
else
CHECK_EQ(toString(requireTypeAtPosition({5, 28})), "(number | string)?"); // a == nil
}
TEST_CASE_FIXTURE(Fixture, "free_type_is_equal_to_an_lvalue")
{
CheckResult result = check(R"(
local function f(a, b: string?)
if a == b then
local foo, bar = a, b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ(toString(requireTypeAtPosition({3, 33})), "unknown"); // a == b
else
CHECK_EQ(toString(requireTypeAtPosition({3, 33})), "a"); // a == b
CHECK_EQ(toString(requireTypeAtPosition({3, 36})), "string?"); // a == b
}
TEST_CASE_FIXTURE(Fixture, "unknown_lvalue_is_not_synonymous_with_other_on_not_equal")
{
CheckResult result = check(R"(
local function f(a: any, b: {x: number}?)
if a ~= b then
local foo, bar = a, b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(requireTypeAtPosition({3, 33})), "any"); // a ~= b
if (FFlag::LuauSolverV2)
CHECK_EQ(toString(requireTypeAtPosition({3, 36})), "{ x: number }?"); // a ~= b
else
CHECK_EQ(toString(requireTypeAtPosition({3, 36})), "{| x: number |}?"); // a ~= b
}
TEST_CASE_FIXTURE(Fixture, "string_not_equal_to_string_or_nil")
{
CheckResult result = check(R"(
local t: {string} = {"hello"}
local a: string = t[1]
local b: string? = nil
if a ~= b then
local foo, bar = a, b
else
local foo, bar = a, b
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(toString(requireTypeAtPosition({6, 29})), "string"); // a ~= b
CHECK_EQ(toString(requireTypeAtPosition({6, 32})), "string?"); // a ~= b
if (FFlag::LuauSolverV2)
{
CHECK_EQ(toString(requireTypeAtPosition({8, 29})), "string?"); // a == b
CHECK_EQ(toString(requireTypeAtPosition({8, 32})), "string?"); // a == b
}
else
{
CHECK_EQ(toString(requireTypeAtPosition({8, 29})), "string"); // a == b
CHECK_EQ(toString(requireTypeAtPosition({8, 32})), "string?"); // a == b
}
}
TEST_CASE_FIXTURE(Fixture, "narrow_property_of_a_bounded_variable")
{
CheckResult result = check(R"(
local t
local u: {x: number?} = {x = nil}
t = u
if t.x then
local foo: number = t.x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "type_narrow_to_vector")
{
CheckResult result = check(R"(
local function f(x)
if type(x) == "vector" then
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("never", toString(requireTypeAtPosition({3, 28})));
else
CHECK_EQ("*error-type*", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "nonoptional_type_can_narrow_to_nil_if_sense_is_true")
{
CheckResult result = check(R"(
local t = {"hello"}
local v = t[2]
if type(v) == "nil" then
local foo = v
else
local foo = v
end
if not (type(v) ~= "nil") then
local foo = v
else
local foo = v
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
// CLI-115281 Types produced by refinements do not consistently get simplified
CHECK_EQ("(nil & string)?", toString(requireTypeAtPosition({4, 24}))); // type(v) == "nil"
CHECK_EQ(
"(boolean | buffer | class | function | number | string | table | thread) & string", toString(requireTypeAtPosition({6, 24}))
); // type(v) ~= "nil"
CHECK_EQ("(nil & string)?", toString(requireTypeAtPosition({10, 24}))); // equivalent to type(v) == "nil"
CHECK_EQ(
"(boolean | buffer | class | function | number | string | table | thread) & string", toString(requireTypeAtPosition({12, 24}))
); // equivalent to type(v) ~= "nil"
}
else
{
CHECK_EQ("nil", toString(requireTypeAtPosition({4, 24}))); // type(v) == "nil"
CHECK_EQ("string", toString(requireTypeAtPosition({6, 24}))); // type(v) ~= "nil"
CHECK_EQ("nil", toString(requireTypeAtPosition({10, 24}))); // equivalent to type(v) == "nil"
CHECK_EQ("string", toString(requireTypeAtPosition({12, 24}))); // equivalent to type(v) ~= "nil"
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typeguard_not_to_be_string")
{
CheckResult result = check(R"(
local function f(x: string | number | boolean)
if type(x) ~= "string" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("boolean | number", toString(requireTypeAtPosition({3, 28}))); // type(x) ~= "string"
CHECK_EQ("string", toString(requireTypeAtPosition({5, 28}))); // type(x) == "string"
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typeguard_narrows_for_table")
{
CheckResult result = check(R"(
local function f(x: string | {x: number} | {y: boolean})
if type(x) == "table" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("{ x: number } | { y: boolean }", toString(requireTypeAtPosition({3, 28}))); // type(x) == "table"
else
CHECK_EQ("{| x: number |} | {| y: boolean |}", toString(requireTypeAtPosition({3, 28}))); // type(x) == "table"
CHECK_EQ("string", toString(requireTypeAtPosition({5, 28}))); // type(x) ~= "table"
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typeguard_narrows_for_functions")
{
CheckResult result = check(R"(
local function weird(x: string | ((number) -> string))
if type(x) == "function" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(number) -> string", toString(requireTypeAtPosition({3, 28}))); // type(x) == "function"
CHECK_EQ("string", toString(requireTypeAtPosition({5, 28}))); // type(x) ~= "function"
}
TEST_CASE_FIXTURE(BuiltinsFixture, "type_guard_can_filter_for_intersection_of_tables")
{
CheckResult result = check(R"(
type XYCoord = {x: number} & {y: number}
local function f(t: XYCoord?)
if type(t) == "table" then
local foo = t
else
local foo = t
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
ToStringOptions opts;
opts.exhaustive = true;
if (FFlag::LuauSolverV2)
CHECK_EQ("{ x: number } & { y: number }", toString(requireTypeAtPosition({4, 28}), opts));
else
CHECK_EQ("{| x: number |} & {| y: number |}", toString(requireTypeAtPosition({4, 28}), opts));
CHECK_EQ("nil", toString(requireTypeAtPosition({6, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "type_guard_can_filter_for_overloaded_function")
{
CheckResult result = check(R"(
type SomeOverloadedFunction = ((number) -> string) & ((string) -> number)
local function f(g: SomeOverloadedFunction?)
if type(g) == "function" then
local foo = g
else
local foo = g
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("((number) -> string) & ((string) -> number)", toString(requireTypeAtPosition({4, 28})));
CHECK_EQ("nil", toString(requireTypeAtPosition({6, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "type_guard_narrowed_into_nothingness")
{
CheckResult result = check(R"(
local function f(t: {x: number})
if type(t) ~= "table" then
local foo = t
error(("Expected a table, got %s"):format(type(t)))
end
return t.x + 1
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
// CLI-115281 Types produced by refinements do not consistently get simplified
CHECK_EQ("{ x: number } & ~table", toString(requireTypeAtPosition({3, 28})));
}
else
CHECK_EQ("never", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(Fixture, "not_a_or_not_b")
{
CheckResult result = check(R"(
local function f(a: number?, b: number?)
if (not a) or (not b) then
local foo = a
local bar = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number?", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number?", toString(requireTypeAtPosition({4, 28})));
}
TEST_CASE_FIXTURE(Fixture, "not_a_or_not_b2")
{
CheckResult result = check(R"(
local function f(a: number?, b: number?)
if not (a and b) then
local foo = a
local bar = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number?", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number?", toString(requireTypeAtPosition({4, 28})));
}
TEST_CASE_FIXTURE(Fixture, "not_a_and_not_b")
{
CheckResult result = check(R"(
local function f(a: number?, b: number?)
if (not a) and (not b) then
local foo = a
local bar = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("nil", toString(requireTypeAtPosition({4, 28})));
}
TEST_CASE_FIXTURE(Fixture, "not_a_and_not_b2")
{
CheckResult result = check(R"(
local function f(a: number?, b: number?)
if not (a or b) then
local foo = a
local bar = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("nil", toString(requireTypeAtPosition({4, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "either_number_or_string")
{
CheckResult result = check(R"(
local function f(x: any, y: unknown)
if type(x) == "number" or type(x) == "string" then
local foo = x
end
if type(y) == "number" or type(y) == "string" then
local foo = y
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("*error-type* | number | string", toString(requireTypeAtPosition({3, 28})));
else
CHECK_EQ("number | string", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number | string", toString(requireTypeAtPosition({6, 28})));
}
TEST_CASE_FIXTURE(Fixture, "not_t_or_some_prop_of_t")
{
CheckResult result = check(R"(
local function f(t: {x: boolean}?)
if not t or t.x then
local foo = t
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
// CLI-115281 Types produced by refinements do not consistently get simplified
CHECK_EQ("({ x: boolean } & { x: ~(false?) })?", toString(requireTypeAtPosition({3, 28})));
}
else
CHECK_EQ("{| x: boolean |}?", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "assert_a_to_be_truthy_then_assert_a_to_be_number")
{
CheckResult result = check(R"(
local a: (number | string)?
assert(a)
local b = a
assert(type(a) == "number")
local c = a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number | string", toString(requireTypeAtPosition({3, 18})));
CHECK_EQ("number", toString(requireTypeAtPosition({5, 18})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "merge_should_be_fully_agnostic_of_hashmap_ordering")
{
// This bug came up because there was a mistake in Luau::merge where zipping on two maps would produce the wrong merged result.
CheckResult result = check(R"(
local function f(b: string | { x: string }, a)
assert(type(a) == "string")
assert(type(b) == "string" or type(b) == "table")
if type(b) == "string" then
local foo = b
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({6, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_the_correct_types_opposite_of_when_a_is_not_number_or_string")
{
CheckResult result = check(R"(
local function f(a: string | number | boolean)
if type(a) ~= "number" and type(a) ~= "string" then
local foo = a
else
local foo = a
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("boolean", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number | string", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "is_truthy_constraint_ifelse_expression")
{
CheckResult result = check(R"(
function f(v:string?)
return if v then v else tostring(v)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({2, 29})));
CHECK_EQ("nil", toString(requireTypeAtPosition({2, 45})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "invert_is_truthy_constraint_ifelse_expression")
{
CheckResult result = check(R"(
function f(v:string?)
return if not v then tostring(v) else v
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({2, 42})));
CHECK_EQ("string", toString(requireTypeAtPosition({2, 50})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "type_comparison_ifelse_expression")
{
CheckResult result = check(R"(
function returnOne(x)
return 1
end
function f(v:any)
return if typeof(v) == "number" then v else returnOne(v)
end
function g(v:unknown)
return if typeof(v) == "number" then v else returnOne(v)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ("*error-type* | number", toString(requireTypeAtPosition({6, 49})));
CHECK_EQ("*error-type* | ~number", toString(requireTypeAtPosition({6, 66})));
}
else
{
CHECK_EQ("number", toString(requireTypeAtPosition({6, 49})));
CHECK_EQ("any", toString(requireTypeAtPosition({6, 66})));
}
CHECK_EQ("number", toString(requireTypeAtPosition({10, 49})));
if (FFlag::LuauSolverV2)
CHECK_EQ("~number", toString(requireTypeAtPosition({10, 66})));
else
CHECK_EQ("unknown", toString(requireTypeAtPosition({10, 66})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "is_truthy_constraint_while_expression")
{
CheckResult result = check(R"(
function f(v:string?)
while v do
local foo = v
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "invert_is_truthy_constraint_while_expression")
{
CheckResult result = check(R"(
function f(v:string?)
while not v do
local foo = v
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_the_correct_types_opposite_of_while_a_is_not_number_or_string")
{
CheckResult result = check(R"(
local function f(a: string | number | boolean)
while type(a) ~= "number" and type(a) ~= "string" do
local foo = a
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("boolean", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "correctly_lookup_a_shadowed_local_that_which_was_previously_refined")
{
CheckResult result = check(R"(
local foo: string? = "hi"
assert(foo)
local foo: number = 5
print(foo:sub(1, 1))
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Type 'number' does not have key 'sub'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "correctly_lookup_property_whose_base_was_previously_refined")
{
CheckResult result = check(R"(
type T = {x: string | number}
local t: T? = {x = "hi"}
if t then
if type(t.x) == "string" then
local foo = t.x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("string", toString(requireTypeAtPosition({5, 30})));
}
TEST_CASE_FIXTURE(Fixture, "correctly_lookup_property_whose_base_was_previously_refined2")
{
CheckResult result = check(R"(
type T = { x: { y: number }? }
local function f(t: T?)
if t and t.x then
local foo = t.x.y
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number", toString(requireTypeAtPosition({5, 32})));
}
TEST_CASE_FIXTURE(Fixture, "apply_refinements_on_astexprindexexpr_whose_subscript_expr_is_constant_string")
{
CheckResult result = check(R"(
type T = { [string]: { prop: number }? }
local t: T = {}
if t["hello"] then
local foo = t["hello"].prop
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "discriminate_from_truthiness_of_x")
{
CheckResult result = check(R"(
type T = {tag: "missing", x: nil} | {tag: "exists", x: string}
local function f(t: T)
if t.x then
local foo = t
else
local bar = t
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
// CLI-115281 Types produced by refinements do not consistently get simplified
CHECK("{ tag: \"exists\", x: string } & { x: ~(false?) }" == toString(requireTypeAtPosition({5, 28})));
CHECK("({ tag: \"exists\", x: string } & { x: ~~(false?) }) | { tag: \"missing\", x: nil }" == toString(requireTypeAtPosition({7, 28})));
}
else
{
CHECK_EQ(R"({| tag: "exists", x: string |})", toString(requireTypeAtPosition({5, 28})));
CHECK_EQ(R"({| tag: "exists", x: string |} | {| tag: "missing", x: nil |})", toString(requireTypeAtPosition({7, 28})));
}
}
TEST_CASE_FIXTURE(Fixture, "discriminate_tag")
{
CheckResult result = check(R"(
type Cat = {tag: "Cat", name: string, catfood: string}
type Dog = {tag: "Dog", name: string, dogfood: string}
type Animal = Cat | Dog
local function f(animal: Animal)
if animal.tag == "Cat" then
local cat = animal
elseif animal.tag == "Dog" then
local dog = animal
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Cat", toString(requireTypeAtPosition({7, 33})));
CHECK_EQ("Dog", toString(requireTypeAtPosition({9, 33})));
}
TEST_CASE_FIXTURE(Fixture, "discriminate_tag_with_implicit_else")
{
CheckResult result = check(R"(
type Cat = {tag: "Cat", name: string, catfood: string}
type Dog = {tag: "Dog", name: string, dogfood: string}
type Animal = Cat | Dog
local function f(animal: Animal)
if animal.tag == "Cat" then
local cat = animal
else
local dog = animal
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Cat", toString(requireTypeAtPosition({7, 33})));
CHECK_EQ("Dog", toString(requireTypeAtPosition({9, 33})));
}
TEST_CASE_FIXTURE(Fixture, "and_or_peephole_refinement")
{
CheckResult result = check(R"(
local function len(a: {any})
return a and #a or nil
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "narrow_boolean_to_true_or_false")
{
CheckResult result = check(R"(
local function f(x: boolean)
if x then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("true", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("false", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(Fixture, "discriminate_on_properties_of_disjoint_tables_where_that_property_is_true_or_false")
{
CheckResult result = check(R"(
type Ok<T> = { ok: true, value: T }
type Err<E> = { ok: false, error: E }
type Result<T, E> = Ok<T> | Err<E>
local function apply<T, E>(t: Result<T, E>, f: (T) -> (), g: (E) -> ())
if t.ok then
f(t.value)
else
g(t.error)
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "refine_a_property_not_to_be_nil_through_an_intersection_table")
{
CheckResult result = check(R"(
type T = {} & {f: ((string) -> string)?}
local function f(t: T, x)
if t.f then
t.f(x)
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(RefinementClassFixture, "discriminate_from_isa_of_x")
{
CheckResult result = check(R"(
type T = {tag: "Part", x: Part} | {tag: "Folder", x: Folder}
local function f(t: T)
if t.x:IsA("Part") then
local foo = t
else
local bar = t
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK(R"({ tag: "Part", x: Part })" == toString(requireTypeAtPosition({5, 28})));
CHECK(R"({ tag: "Folder", x: Folder })" == toString(requireTypeAtPosition({7, 28})));
}
else
{
CHECK_EQ(R"({| tag: "Part", x: Part |})", toString(requireTypeAtPosition({5, 28})));
CHECK_EQ(R"({| tag: "Folder", x: Folder |})", toString(requireTypeAtPosition({7, 28})));
}
}
TEST_CASE_FIXTURE(RefinementClassFixture, "typeguard_cast_free_table_to_vector")
{
// CLI-115286 - Refining via type(x) == 'vector' does not work in the new solver
DOES_NOT_PASS_NEW_SOLVER_GUARD();
CheckResult result = check(R"(
local function f(vec)
local X, Y, Z = vec.X, vec.Y, vec.Z
if type(vec) == "vector" then
local foo = vec
elseif typeof(vec) == "Instance" then
local foo = vec
else
local foo = vec
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Vector3", toString(requireTypeAtPosition({5, 28}))); // type(vec) == "vector"
CHECK_EQ("never", toString(requireTypeAtPosition({7, 28}))); // typeof(vec) == "Instance"
CHECK_EQ("{+ X: a, Y: b, Z: c +}", toString(requireTypeAtPosition({9, 28}))); // type(vec) ~= "vector" and typeof(vec) ~= "Instance"
}
TEST_CASE_FIXTURE(RefinementClassFixture, "typeguard_cast_instance_or_vector3_to_vector")
{
CheckResult result = check(R"(
local function f(x: Instance | Vector3)
if typeof(x) == "Vector3" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Vector3", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Instance", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "type_narrow_for_all_the_userdata")
{
CheckResult result = check(R"(
local function f(x: string | number | Instance | Vector3)
if type(x) == "userdata" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Instance | Vector3", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number | string", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "type_narrow_but_the_discriminant_type_isnt_a_class")
{
CheckResult result = check(R"(
local function f(x: string | number | Instance | Vector3)
if type(x) == "any" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ("never", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Instance | Vector3 | number | string", toString(requireTypeAtPosition({5, 28})));
}
else
{
CHECK_EQ("*error-type*", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("*error-type*", toString(requireTypeAtPosition({5, 28})));
}
}
TEST_CASE_FIXTURE(RefinementClassFixture, "eliminate_subclasses_of_instance")
{
CheckResult result = check(R"(
local function f(x: Part | Folder | string)
if typeof(x) == "Instance" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Folder | Part", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("string", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "narrow_from_subclasses_of_instance_or_string_or_vector3")
{
CheckResult result = check(R"(
local function f(x: Part | Folder | string | Vector3)
if typeof(x) == "Instance" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Folder | Part", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Vector3 | string", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "x_as_any_if_x_is_instance_elseif_x_is_table")
{
// CLI-117136 - this code doesn't finish constraint solving and has blocked types in the output
if (FFlag::LuauSolverV2)
return;
CheckResult result = check(R"(
--!nonstrict
local function f(x)
if typeof(x) == "Instance" and x:IsA("Folder") then
local foo = x
elseif typeof(x) == "table" then
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ("Folder & Instance & {- -}", toString(requireTypeAtPosition({5, 28})));
CHECK_EQ("(~Folder | ~Instance) & {- -} & never", toString(requireTypeAtPosition({7, 28})));
}
else
{
CHECK_EQ("Folder", toString(requireTypeAtPosition({5, 28})));
CHECK_EQ("any", toString(requireTypeAtPosition({7, 28})));
}
}
TEST_CASE_FIXTURE(RefinementClassFixture, "refine_param_of_type_instance_without_using_typeof")
{
CheckResult result = check(R"(
local function f(x: Instance)
if x:IsA("Folder") then
local foo = x
elseif typeof(x) == "table" then
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Folder", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("never", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "refine_param_of_type_folder_or_part_without_using_typeof")
{
CheckResult result = check(R"(
local function f(x: Part | Folder)
if x:IsA("Folder") then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Folder", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Part", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "isa_type_refinement_must_be_known_ahead_of_time")
{
// CLI-115087 - The new solver does not consistently combine tables with
// class types when they appear in the upper bounds of a free type.
DOES_NOT_PASS_NEW_SOLVER_GUARD();
CheckResult result = check(R"(
local function f(x): Instance
if x:IsA("Folder") then
local foo = x
else
local foo = x
end
return x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Instance", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Instance", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "x_is_not_instance_or_else_not_part")
{
// CLI-117135 - RefinementTests.x_is_not_instance_or_else_not_part not correctly applying refinements to a function parameter
if (FFlag::LuauSolverV2)
return;
CheckResult result = check(R"(
local function f(x: Part | Folder | string)
if typeof(x) ~= "Instance" or not x:IsA("Part") then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Folder | string", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Part", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "typeguard_doesnt_leak_to_elseif")
{
CheckResult result = check(R"(
function f(a)
if type(a) == "boolean" then
local a1 = a
elseif a.fn() then
local a2 = a
else
local a3 = a
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknowns")
{
CheckResult result = check(R"(
local function f(x: unknown)
if type(x) == "string" then
local foo = x
else
local bar = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ("string", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("~string", toString(requireTypeAtPosition({5, 28})));
}
else
{
CHECK_EQ("string", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("unknown", toString(requireTypeAtPosition({5, 28})));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_boolean")
{
CheckResult result = check(R"(
local function f(x: number | boolean)
if typeof(x) == "boolean" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("boolean", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_thread")
{
CheckResult result = check(R"(
local function f(x: number | thread)
if typeof(x) == "thread" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("thread", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_buffer")
{
CheckResult result = check(R"(
local function f(x: number | buffer)
if typeof(x) == "buffer" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("buffer", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("number", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "falsiness_of_TruthyPredicate_narrows_into_nil")
{
CheckResult result = check(R"(
local function f(t: {number})
local x = t[1]
if not x then
local foo = x
else
local bar = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({4, 28})));
CHECK_EQ("number", toString(requireTypeAtPosition({6, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "what_nonsensical_condition")
{
CheckResult result = check(R"(
local function f(x)
if type(x) == "string" and type(x) == "number" then
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("never", toString(requireTypeAtPosition({3, 28})));
}
TEST_CASE_FIXTURE(Fixture, "else_with_no_explicit_expression_should_also_refine_the_tagged_union")
{
CheckResult result = check(R"(
type Ok<T> = { tag: "ok", value: T }
type Err<E> = { tag: "err", err: E }
type Result<T, E> = Ok<T> | Err<E>
function and_then<T, U, E>(r: Result<T, E>, f: (T) -> U): Result<U, E>
if r.tag == "ok" then
return { tag = "ok", value = f(r.value) }
else
return r
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "fuzz_filtered_refined_types_are_followed")
{
CheckResult result = check(R"(
local _
do
local _ = _ ~= _ or _ or _
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknown_to_table_then_take_the_length")
{
CheckResult result = check(R"(
local function f(x: unknown)
if typeof(x) == "table" then
local len = #x
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("table", toString(requireTypeAtPosition({3, 29})));
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("unknown", toString(requireTypeAtPosition({3, 29})));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknown_to_table_then_clone_it")
{
CheckResult result = check(R"(
local function f(x: unknown)
if typeof(x) == "table" then
local cloned: {} = table.clone(x)
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
}
TEST_CASE_FIXTURE(RefinementClassFixture, "refine_a_param_that_got_resolved_during_constraint_solving_stage")
{
// CLI-117134 - Applying a refinement causes an optional value access error.
if (FFlag::LuauSolverV2)
return;
CheckResult result = check(R"(
type Id<T> = T
local function f(x: Id<Id<Part | Folder> | Id<string>>)
if typeof(x) ~= "string" and x:IsA("Part") then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Part", toString(requireTypeAtPosition({5, 28})));
CHECK_EQ("Folder | string", toString(requireTypeAtPosition({7, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "refine_a_param_that_got_resolved_during_constraint_solving_stage_2")
{
CheckResult result = check(R"(
local function hof(f: (Instance) -> ()) end
hof(function(inst)
if inst:IsA("Part") then
local foo = inst
else
local foo = inst
end
end)
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Part", toString(requireTypeAtPosition({5, 28})));
if (FFlag::LuauSolverV2)
CHECK_EQ("Instance & ~Part", toString(requireTypeAtPosition({7, 28})));
else
CHECK_EQ("Instance", toString(requireTypeAtPosition({7, 28})));
}
TEST_CASE_FIXTURE(Fixture, "refine_a_property_of_some_global")
{
CheckResult result = check(R"(
foo = { bar = 5 :: number? }
if foo.bar then
local bar = foo.bar
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("number", toString(requireTypeAtPosition({4, 30})));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "dataflow_analysis_can_tell_refinements_when_its_appropriate_to_refine_into_nil_or_never")
{
CheckResult result = check(R"(
local function f(t: {string}, s: string)
local v1 = t[5]
local v2 = v1
if typeof(v1) == "nil" then
local foo = v1
else
local foo = v1
end
if typeof(v2) == "nil" then
local foo = v2
else
local foo = v2
end
if typeof(s) == "nil" then
local foo = s -- line 18
else
local foo = s -- line 20
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({6, 28})));
CHECK_EQ("string", toString(requireTypeAtPosition({8, 28})));
CHECK_EQ("nil", toString(requireTypeAtPosition({12, 28})));
CHECK_EQ("string", toString(requireTypeAtPosition({14, 28})));
if (FFlag::LuauSolverV2)
{
// CLI-115281 - Types produced by refinements don't always get simplified
CHECK_EQ("nil & string", toString(requireTypeAtPosition({18, 28})));
CHECK_EQ("string", toString(requireTypeAtPosition({20, 28})));
}
else
{
CHECK_EQ("nil", toString(requireTypeAtPosition({18, 28})));
CHECK_EQ("string", toString(requireTypeAtPosition({20, 28})));
}
}
TEST_CASE_FIXTURE(Fixture, "cat_or_dog_through_a_local")
{
CheckResult result = check(R"(
type Cat = { tag: "cat", catfood: string }
type Dog = { tag: "dog", dogfood: string }
type Animal = Cat | Dog
local function f(animal: Animal)
local tag = animal.tag
if tag == "dog" then
local dog = animal
elseif tag == "cat" then
local cat = animal
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Cat | Dog", toString(requireTypeAtPosition({8, 28})));
CHECK_EQ("Cat | Dog", toString(requireTypeAtPosition({10, 28})));
}
TEST_CASE_FIXTURE(Fixture, "prove_that_dataflow_analysis_isnt_doing_alias_tracking_yet")
{
CheckResult result = check(R"(
local function f(tag: "cat" | "dog")
local tag2 = tag
if tag2 == "cat" then
local foo = tag
else
local foo = tag
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(R"("cat" | "dog")", toString(requireTypeAtPosition({5, 28})));
CHECK_EQ(R"("cat" | "dog")", toString(requireTypeAtPosition({7, 28})));
}
TEST_CASE_FIXTURE(Fixture, "fail_to_refine_a_property_of_subscript_expression")
{
CheckResult result = check(R"(
type Foo = { foo: number? }
local function f(t: {Foo})
if t[1].foo then
local foo = t[1].foo
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number?", toString(requireTypeAtPosition({4, 34})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "type_annotations_arent_relevant_when_doing_dataflow_analysis")
{
CheckResult result = check(R"(
local function s() return "hello" end
local function f(t: {string})
local s1: string = t[5]
local s2: string = s()
if typeof(s1) == "nil" and typeof(s2) == "nil" then
local foo = s1
local bar = s2
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("nil", toString(requireTypeAtPosition({8, 28})));
if (FFlag::LuauSolverV2)
{
// CLI-115478 - This should be never
CHECK_EQ("nil", toString(requireTypeAtPosition({9, 28})));
}
else
CHECK_EQ("nil", toString(requireTypeAtPosition({9, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "function_call_with_colon_after_refining_not_to_be_nil")
{
ScopedFastFlag sff{FFlag::LuauSolverV2, true};
CheckResult result = check(R"(
--!strict
export type Observer<T> = {
read complete: ((self: Observer<T>) -> ())?,
}
local function _f(handler: Observer<any>)
assert(handler.complete ~= nil)
handler:complete() -- incorrectly gives Value of type '((Observer<any>) -> ())?' could be nil
handler.complete(handler) -- works fine, both forms should avoid the error
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "refinements_should_not_affect_assignment")
{
CheckResult result = check(R"(
local a: unknown = true
if a == true then
a = 'not even remotely similar to a boolean'
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refinements_should_preserve_error_suppression")
{
CheckResult result = check(R"(
local a: any = {}
local b
if typeof(a) == "table" then
b = a.field
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "many_refinements_on_val")
{
CheckResult result = check(R"(
local function is_nan(val: any): boolean
return type(val) == "number" and val ~= val
end
local function is_js_boolean(val: any): boolean
return not not val and val ~= 0 and val ~= "" and not is_nan(val)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(any) -> boolean", toString(requireType("is_nan")));
CHECK_EQ("(any) -> boolean", toString(requireType("is_js_boolean")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "refine_unknown_to_table")
{
ScopedFastFlag sff{FFlag::LuauSolverV2, true};
// this test is DCR-only as an instance of DCR fixing a bug in the old solver
CheckResult result = check(R"(
local function f(a: unknown)
if typeof(a) == "table" then
for i, v in a do
return i, v
end
end
error("")
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(unknown) -> (unknown, unknown)", toString(requireType("f")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "conditional_refinement_should_stay_error_suppressing")
{
ScopedFastFlag sff{FFlag::LuauSolverV2, true};
CheckResult result = check(R"(
local function test(element: any?)
if element then
local owner = element._owner
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "globals_can_be_narrowed_too")
{
CheckResult result = check(R"(
if typeof(string) == 'string' then
local foo = string
end
)");
if (FFlag::LuauSolverV2)
{
// CLI-114134
CHECK("string & typeof(string)" == toString(requireTypeAtPosition(Position{2, 24})));
}
else
CHECK("never" == toString(requireTypeAtPosition(Position{2, 24})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau_polyfill_isindexkey_refine_conjunction")
{
CheckResult result = check(R"(
local function isIndexKey(k, contiguousLength)
return type(k) == "number"
and k <= contiguousLength -- nothing out of bounds
and 1 <= k -- nothing illegal for array indices
and math.floor(k) == k -- no float keys
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau_polyfill_isindexkey_refine_conjunction_variant")
{
CheckResult result = check(R"(
local function isIndexKey(k, contiguousLength: number)
return type(k) == "number"
and k <= contiguousLength -- nothing out of bounds
and 1 <= k -- nothing illegal for array indices
and math.floor(k) == k -- no float keys
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "ex")
{
CheckResult result = check(R"(
local function f(x: string | number)
if typeof((x)) == "string" then
local y = x
end
end
)");
TypeId t = requireTypeAtPosition({3, 18});
CHECK("string" == toString(t));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "mutate_prop_of_some_refined_symbol")
{
CheckResult result = check(R"(
local function instances(): {Instance} error("") end
local function vec3(x, y, z): Vector3 error("") end
for _, object in ipairs(instances()) do
if object:IsA("Part") then
object.Position = vec3(1, 2, 3)
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(RefinementClassFixture, "mutate_prop_of_some_refined_symbol_2")
{
CheckResult result = check(R"(
type Result<T, E> = never
| { tag: "ok", value: T }
| { tag: "err", error: E }
local function results(): {Result<number, string>} error("") end
for _, res in ipairs(results()) do
if res.tag == "ok" then
res.value = 7
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "ensure_t_after_return_references_all_reachable_points")
{
CheckResult result = check(R"(
local t = {}
local function f(k: string)
if t[k] ~= nil then
return
end
t[k] = 5
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("{ [string]: number }", toString(requireTypeAtPosition({8, 12}), {true}));
}
TEST_CASE_FIXTURE(Fixture, "long_disjunction_of_refinements_should_not_trip_recursion_counter")
{
CHECK_NOTHROW(check(R"(
function(obj)
if script.Parent.SeatNumber.Value == "1D" or
script.Parent.SeatNumber.Value == "2D" or
script.Parent.SeatNumber.Value == "3D" or
script.Parent.SeatNumber.Value == "4D" or
script.Parent.SeatNumber.Value == "5D" or
script.Parent.SeatNumber.Value == "6D" or
script.Parent.SeatNumber.Value == "7D" or
script.Parent.SeatNumber.Value == "8D" or
script.Parent.SeatNumber.Value == "9D" or
script.Parent.SeatNumber.Value == "10D" or
script.Parent.SeatNumber.Value == "11D" or
script.Parent.SeatNumber.Value == "12D" or
script.Parent.SeatNumber.Value == "13D" or
script.Parent.SeatNumber.Value == "14D" or
script.Parent.SeatNumber.Value == "15D" or
script.Parent.SeatNumber.Value == "16D" or
script.Parent.SeatNumber.Value == "1C" or
script.Parent.SeatNumber.Value == "2C" or
script.Parent.SeatNumber.Value == "3C" or
script.Parent.SeatNumber.Value == "4C" or
script.Parent.SeatNumber.Value == "5C" or
script.Parent.SeatNumber.Value == "6C" or
script.Parent.SeatNumber.Value == "7C" or
script.Parent.SeatNumber.Value == "8C" or
script.Parent.SeatNumber.Value == "9C" or
script.Parent.SeatNumber.Value == "10C" or
script.Parent.SeatNumber.Value == "11C" or
script.Parent.SeatNumber.Value == "12C" or
script.Parent.SeatNumber.Value == "13C" or
script.Parent.SeatNumber.Value == "14C" or
script.Parent.SeatNumber.Value == "15C" or
script.Parent.SeatNumber.Value == "16C" then
end
)"));
}
TEST_CASE_FIXTURE(Fixture, "more_complex_long_disjunction_of_refinements_shouldnt_trip_ice")
{
CHECK_NOTHROW(check(R"(
script:connect(function(obj)
if script.Parent.SeatNumber.Value == "1D" or
script.Parent.SeatNumber.Value == "2D" or
script.Parent.SeatNumber.Value == "3D" or
script.Parent.SeatNumber.Value == "4D" or
script.Parent.SeatNumber.Value == "5D" or
script.Parent.SeatNumber.Value == "6D" or
script.Parent.SeatNumber.Value == "7D" or
script.Parent.SeatNumber.Value == "8D" or
script.Parent.SeatNumber.Value == "9D" or
script.Parent.SeatNumber.Value == "10D" or
script.Parent.SeatNumber.Value == "11D" or
script.Parent.SeatNumber.Value == "12D" or
script.Parent.SeatNumber.Value == "13D" or
script.Parent.SeatNumber.Value == "14D" or
script.Parent.SeatNumber.Value == "15D" or
script.Parent.SeatNumber.Value == "16D" or
script.Parent.SeatNumber.Value == "1C" or
script.Parent.SeatNumber.Value == "2C" or
script.Parent.SeatNumber.Value == "3C" or
script.Parent.SeatNumber.Value == "4C" or
script.Parent.SeatNumber.Value == "5C" or
script.Parent.SeatNumber.Value == "6C" or
script.Parent.SeatNumber.Value == "7C" or
script.Parent.SeatNumber.Value == "8C" or
script.Parent.SeatNumber.Value == "9C" or
script.Parent.SeatNumber.Value == "10C" or
script.Parent.SeatNumber.Value == "11C" or
script.Parent.SeatNumber.Value == "12C" or
script.Parent.SeatNumber.Value == "13C" or
script.Parent.SeatNumber.Value == "14C" or
script.Parent.SeatNumber.Value == "15C" or
script.Parent.SeatNumber.Value == "16C" then
end)
)"));
}
TEST_CASE_FIXTURE(Fixture, "refinements_should_avoid_building_up_big_intersect_families")
{
CHECK_NOTHROW(check(R"(
script:connect(function(obj)
if script.Parent.SeatNumber.Value == "1D" or script.Parent.SeatNumber.Value == "2D" or script.Parent.SeatNumber.Value == "3D" or script.Parent.SeatNumber.Value == "4D" or script.Parent.SeatNumber.Value == "5D" or script.Parent.SeatNumber.Value == "6D" or script.Parent.SeatNumber.Value == "7D" or script.Parent.SeatNumber.Value == "8D" or script.Parent.SeatNumber.Value == "9D" or script.Parent.SeatNumber.Value == "10D" or script.Parent.SeatNumber.Value == "11D" or script.Parent.SeatNumber.Value == "12D" or script.Parent.SeatNumber.Value == "13D" or script.Parent.SeatNumber.Value == "14D" or script.Parent.SeatNumber.Value == "15D" or script.Parent.SeatNumber.Value == "16D" or script.Parent.SeatNumber.Value == "1C" or script.Parent.SeatNumber.Value == "2C" or script.Parent.SeatNumber.Value == "3C" or script.Parent.SeatNumber.Value == "4C" or script.Parent.SeatNumber.Value == "5C" or script.Parent.SeatNumber.Value == "6C" or script.Parent.SeatNumber.Value == "7C" or script.Parent.SeatNumber.Value == "8C" or script.Parent.SeatNumber.Value == "9C" or script.Parent.SeatNumber.Value == "10C" or script.Parent.SeatNumber.Value == "11C" or script.Parent.SeatNumber.Value == "12C" or script.Parent.SeatNumber.Value == "13C" or script.Parent.SeatNumber.Value == "14C" or script.Parent.SeatNumber.Value == "15C" or script.Parent.SeatNumber.Value == "16C" then
if p.Name == script.Parent.Parent.Parent.Parent.Parent.Parent.MainParts.CD.SurfaceGui[script.Parent.SeatNumber.Value].Player.Value or script.Parent.Parent.Parent.Parent.Parent.Parent.MainParts.CD.SurfaceGui[script.Parent.SeatNumber.Value].Player.Value == "" then
else
if script.Parent:FindFirstChild("SeatWeld") then
end
end
else
if p.Name == script.Parent.Parent.Parent.Parent.Parent.Parent.MainParts.AB.SurfaceGui[script.Parent.SeatNumber.Value].Player.Value or script.Parent.Parent.Parent.Parent.Parent.Parent.MainParts.AB.SurfaceGui[script.Parent.SeatNumber.Value].Player.Value == "" then
print("Allowed")
else
if script.Parent:FindFirstChild("SeatWeld") then
end
end
end
end)
)"));
}
TEST_CASE_FIXTURE(Fixture, "refinements_table_intersection_limits" * doctest::timeout(0.5))
{
CheckResult result = check(R"(
--!strict
type Dir = {
a: number?, b: number?, c: number?, d: number?, e: number?, f: number?,
g: number?, h: number?, i: number?, j: number?, k: number?, l: number?,
m: number?, n: number?, o: number?, p: number?, q: number?, r: number?,
}
local function test(dirs: {Dir})
for k, dir in dirs
local success, message = pcall(function()
assert(dir.a == nil or type(dir.a) == "number")
assert(dir.b == nil or type(dir.b) == "number")
assert(dir.c == nil or type(dir.c) == "number")
assert(dir.d == nil or type(dir.d) == "number")
assert(dir.e == nil or type(dir.e) == "number")
assert(dir.f == nil or type(dir.f) == "number")
assert(dir.g == nil or type(dir.g) == "number")
assert(dir.h == nil or type(dir.h) == "number")
assert(dir.i == nil or type(dir.i) == "number")
assert(dir.j == nil or type(dir.j) == "number")
assert(dir.k == nil or type(dir.k) == "number")
assert(dir.l == nil or type(dir.l) == "number")
assert(dir.m == nil or type(dir.m) == "number")
assert(dir.n == nil or type(dir.n) == "number")
assert(dir.o == nil or type(dir.o) == "number")
assert(dir.p == nil or type(dir.p) == "number")
assert(dir.q == nil or type(dir.q) == "number")
assert(dir.r == nil or type(dir.r) == "number")
assert(dir.t == nil or type(dir.t) == "number")
assert(dir.u == nil or type(dir.u) == "number")
assert(dir.v == nil or type(dir.v) == "number")
local checkpoint = dir
checkpoint.w = 1
end)
assert(success)
end
end
)");
}
TEST_CASE_FIXTURE(RefinementClassFixture, "typeof_instance_refinement")
{
CheckResult result = check(R"(
local function f(x: Instance | Vector3)
if typeof(x) == "Instance" then
local foo = x
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Instance", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Vector3", toString(requireTypeAtPosition({5, 28})));
}
TEST_CASE_FIXTURE(RefinementClassFixture, "typeof_instance_error")
{
CheckResult result = check(R"(
local function f(x: Part)
if typeof(x) == "Instance" then
local foo : Folder = x
end
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(RefinementClassFixture, "typeof_instance_isa_refinement")
{
CheckResult result = check(R"(
local function f(x: Part | Folder | string)
if typeof(x) == "Instance" then
local foo = x
if foo:IsA("Folder") then
local bar = foo
end
else
local foo = x
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Folder | Part", toString(requireTypeAtPosition({3, 28})));
CHECK_EQ("Folder", toString(requireTypeAtPosition({5, 32})));
CHECK_EQ("string", toString(requireTypeAtPosition({8, 28})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "remove_recursive_upper_bound_when_generalizing")
{
ScopedFastFlag sffs[] = {
{FFlag::LuauSolverV2, true},
{FFlag::DebugLuauEqSatSimplification, true},
{FFlag::LuauGeneralizationRemoveRecursiveUpperBound2, true},
};
LUAU_REQUIRE_NO_ERRORS(check(R"(
local t = {"hello"}
local v = t[2]
if type(v) == "nil" then
local foo = v
end
)"));
CHECK_EQ("(nil & string)?", toString(requireTypeAtPosition({4, 24})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "nonnil_refinement_on_generic")
{
ScopedFastFlag sff{FFlag::LuauIntersectNotNil, true};
CheckResult result = check(R"(
local function printOptional<T>(item: T?, printer: (T) -> string): string
if item ~= nil then
return printer(item)
else
return ""
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("T & ~nil", toString(requireTypeAtPosition({3, 31})));
else
CHECK_EQ("T", toString(requireTypeAtPosition({3, 31})));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "truthy_refinement_on_generic")
{
ScopedFastFlag sff{FFlag::LuauIntersectNotNil, true};
CheckResult result = check(R"(
local function printOptional<T>(item: T?, printer: (T) -> string): string
if item then
return printer(item)
else
return ""
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("T & ~(false?)", toString(requireTypeAtPosition({3, 31})));
else
CHECK_EQ("T", toString(requireTypeAtPosition({3, 31})));
}
TEST_CASE_FIXTURE(Fixture, "truthy_call_of_function_with_table_value_as_argument_should_not_refine_value_as_never")
{
ScopedFastFlag sff{FFlag::LuauSkipNoRefineDuringRefinement, true};
CheckResult result = check(R"(
type Item = {}
local function predicate(value: Item): boolean
return true
end
local function checkValue(value: Item)
if predicate(value) then
local _ = value
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Item", toString(requireTypeAtPosition({8, 27})));
CHECK_EQ("Item", toString(requireTypeAtPosition({9, 28})));
}
TEST_SUITE_END();