luau/tests/TypeInfer.tables.test.cpp
aaron ae459a0197
Sync to upstream/release/616 (#1184)
# What's Changed

* Add a compiler hint to improve Luau memory allocation inlining

### New Type Solver

* Added a system for recommending explicit type annotations to users in
cases where we've inferred complex generic types with type families.
* Marked string library functions as `@checked` for use in new
non-strict mode.
* Fixed a bug with new non-strict mode where we would incorrectly report
arity mismatches when missing optional arguments.
* Implement an occurs check for unifications that would produce
self-recursive types.
* Fix bug where overload resolution would fail when applied to
non-overloaded functions.
* Fix bug that caused the subtyping to report an error whenever a
generic was instantiated in an invariant context.
* Fix crash caused by `SetPropConstraint` not blocking properly.

### Native Code Generation

* Implement optimization to eliminate dead stores
* Optimize vector ops for X64 when the source is computed (thanks,
@zeux!)
* Use more efficient lowering for UNM_* (thanks, @zeux!)

---

### Internal Contributors

Co-authored-by: Aaron Weiss <aaronweiss@roblox.com>
Co-authored-by: Alexander McCord <amccord@roblox.com>
Co-authored-by: Andy Friesen <afriesen@roblox.com>
Co-authored-by: David Cope <dcope@roblox.com>
Co-authored-by: Lily Brown <lbrown@roblox.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>

---------

Co-authored-by: Alexander McCord <amccord@roblox.com>
Co-authored-by: Andy Friesen <afriesen@roblox.com>
Co-authored-by: Vighnesh <vvijay@roblox.com>
Co-authored-by: Aviral Goel <agoel@roblox.com>
Co-authored-by: David Cope <dcope@roblox.com>
Co-authored-by: Lily Brown <lbrown@roblox.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>
2024-03-08 16:47:53 -08:00

4179 lines
112 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#include "Luau/BuiltinDefinitions.h"
#include "Luau/Common.h"
#include "Luau/Frontend.h"
#include "Luau/ToString.h"
#include "Luau/TypeInfer.h"
#include "Luau/Type.h"
#include "Fixture.h"
#include "ScopedFlags.h"
#include "doctest.h"
#include <algorithm>
using namespace Luau;
LUAU_FASTFLAG(LuauLowerBoundsCalculation);
LUAU_FASTFLAG(DebugLuauDeferredConstraintResolution);
LUAU_FASTFLAG(LuauInstantiateInSubtyping);
LUAU_FASTFLAG(LuauAlwaysCommitInferencesOfFunctionCalls);
LUAU_FASTFLAG(LuauFixIndexerSubtypingOrdering);
LUAU_FASTFLAG(DebugLuauSharedSelf);
LUAU_FASTFLAG(LuauReadWritePropertySyntax);
TEST_SUITE_BEGIN("TableTests");
TEST_CASE_FIXTURE(Fixture, "basic")
{
CheckResult result = check("local t = {foo = \"bar\", baz = 9, quux = nil}");
LUAU_REQUIRE_NO_ERRORS(result);
const TableType* tType = get<TableType>(requireType("t"));
REQUIRE(tType != nullptr);
std::optional<Property> fooProp = get(tType->props, "foo");
REQUIRE(bool(fooProp));
CHECK_EQ(PrimitiveType::String, getPrimitiveType(fooProp->type()));
std::optional<Property> bazProp = get(tType->props, "baz");
REQUIRE(bool(bazProp));
CHECK_EQ(PrimitiveType::Number, getPrimitiveType(bazProp->type()));
std::optional<Property> quuxProp = get(tType->props, "quux");
REQUIRE(bool(quuxProp));
CHECK_EQ(PrimitiveType::NilType, getPrimitiveType(quuxProp->type()));
}
TEST_CASE_FIXTURE(Fixture, "augment_table")
{
CheckResult result = check(R"(
local t = {}
t.foo = 'bar'
)");
LUAU_REQUIRE_NO_ERRORS(result);
const TableType* tType = get<TableType>(requireType("t"));
REQUIRE(tType != nullptr);
CHECK("{ foo: string }" == toString(requireType("t"), {true}));
}
TEST_CASE_FIXTURE(Fixture, "augment_nested_table")
{
CheckResult result = check(R"(
local t = { p = {} }
t.p.foo = 'bar'
)");
LUAU_REQUIRE_NO_ERRORS(result);
TableType* tType = getMutable<TableType>(requireType("t"));
REQUIRE(tType != nullptr);
REQUIRE(tType->props.find("p") != tType->props.end());
const TableType* pType = get<TableType>(tType->props["p"].type());
REQUIRE(pType != nullptr);
CHECK("{ p: { foo: string } }" == toString(requireType("t"), {true}));
}
TEST_CASE_FIXTURE(Fixture, "assign_key_at_index_expr")
{
CheckResult result = check(R"(
function f(t: {[string]: number})
t["hello"] = 1
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
// We had a bug where we forgot to record the astType of this particular node.
CHECK("string" == toString(requireTypeAtPosition({2, 19})));
}
TEST_CASE_FIXTURE(Fixture, "index_expression_is_checked_against_the_indexer_type")
{
CheckResult result = check(R"(
function f(t: {[boolean]: number})
t["hello"] = 15
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_MESSAGE(get<CannotExtendTable>(result.errors[0]), "Expected CannotExtendTable but got " << toString(result.errors[0]));
else
CHECK(get<TypeMismatch>(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "cannot_augment_sealed_table")
{
CheckResult result = check(R"(
function mkt()
return {prop=999}
end
local t = mkt()
t.foo = 'bar'
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeError& err = result.errors[0];
CHECK(err.location == Location{Position{6, 8}, Position{6, 13}});
CannotExtendTable* error = get<CannotExtendTable>(err);
REQUIRE_MESSAGE(error != nullptr, "Expected CannotExtendTable but got: " << toString(err));
// TODO: better, more robust comparison of type vars
auto s = toString(error->tableType, ToStringOptions{/*exhaustive*/ true});
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ(s, "{ prop: number }");
else
CHECK_EQ(s, "{| prop: number |}");
CHECK_EQ(error->prop, "foo");
CHECK_EQ(error->context, CannotExtendTable::Property);
}
TEST_CASE_FIXTURE(Fixture, "dont_seal_an_unsealed_table_by_passing_it_to_a_function_that_takes_a_sealed_table")
{
CheckResult result = check(R"(
type T = {[number]: number}
function f(arg: T) end
local B = {}
f(B)
function B:method() end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "updating_sealed_table_prop_is_ok")
{
CheckResult result = check("local t = {prop=999} t.prop = 0");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cannot_change_type_of_unsealed_table_prop")
{
CheckResult result = check(R"(
local t = {}
t.prop = 999
t.prop = 'hello'
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "cannot_change_type_of_table_prop")
{
CheckResult result = check("local t = {prop=999} t.prop = 'hello'");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "report_sensible_error_when_adding_a_value_to_a_nonexistent_prop")
{
CheckResult result = check(R"(
local t = {}
t.foo[1] = 'one'
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
INFO(result.errors[0]);
UnknownProperty* err = get<UnknownProperty>(result.errors[0]);
REQUIRE(err);
CHECK("t" == toString(err->table));
CHECK("foo" == err->key);
}
TEST_CASE_FIXTURE(Fixture, "function_calls_can_produce_tables")
{
CheckResult result = check("function get_table() return {prop=999} end get_table().prop = 0");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "function_calls_produces_sealed_table_given_unsealed_table")
{
CheckResult result = check(R"(
function f() return {} end
f().foo = 'fail'
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "tc_member_function")
{
CheckResult result = check("local T = {} function T:foo() return 5 end");
LUAU_REQUIRE_NO_ERRORS(result);
const TableType* tableType = get<TableType>(requireType("T"));
REQUIRE(tableType != nullptr);
std::optional<Property> fooProp = get(tableType->props, "foo");
REQUIRE(bool(fooProp));
const FunctionType* methodType = get<FunctionType>(follow(fooProp->type()));
REQUIRE(methodType != nullptr);
}
TEST_CASE_FIXTURE(Fixture, "tc_member_function_2")
{
CheckResult result = check("local T = {U={}} function T.U:foo() return 5 end");
LUAU_REQUIRE_NO_ERRORS(result);
const TableType* tableType = get<TableType>(requireType("T"));
REQUIRE(tableType != nullptr);
std::optional<Property> uProp = get(tableType->props, "U");
REQUIRE(bool(uProp));
TypeId uType = uProp->type();
const TableType* uTable = get<TableType>(uType);
REQUIRE(uTable != nullptr);
std::optional<Property> fooProp = get(uTable->props, "foo");
REQUIRE(bool(fooProp));
const FunctionType* methodType = get<FunctionType>(follow(fooProp->type()));
REQUIRE(methodType != nullptr);
std::vector<TypeId> methodArgs = flatten(methodType->argTypes).first;
REQUIRE_EQ(methodArgs.size(), 1);
// TODO(rblanckaert): Revist when we can bind self at function creation time
// REQUIRE_EQ(*methodArgs[0], *uType);
}
TEST_CASE_FIXTURE(Fixture, "call_method")
{
CheckResult result = check(R"(
local T = {}
T.x = 0
function T:method()
return self.x
end
local a = T:method()
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*builtinTypes->numberType, *requireType("a"));
}
TEST_CASE_FIXTURE(Fixture, "call_method_with_explicit_self_argument")
{
CheckResult result = check(R"(
local T = {}
T.x = 0
function T:method()
return self.x
end
local a = T.method(T)
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "used_dot_instead_of_colon")
{
CheckResult result = check(R"(
local T = {}
T.x = 0
function T:method()
return self.x
end
local a = T.method()
)");
auto it = std::find_if(result.errors.begin(), result.errors.end(), [](const TypeError& e) {
return nullptr != get<FunctionRequiresSelf>(e);
});
REQUIRE(it != result.errors.end());
}
TEST_CASE_FIXTURE(BuiltinsFixture, "used_colon_correctly")
{
CheckResult result = check(R"(
--!nonstrict
local upVector = {}
function upVector:Dot(lookVector)
return 8
end
local v = math.abs(upVector:Dot(5))
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "used_dot_instead_of_colon_but_correctly")
{
CheckResult result = check(R"(
local T = {}
T.x = 0
function T:method(arg1, arg2)
return self.x
end
local a = T.method(T, 6, 7)
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "used_colon_instead_of_dot")
{
CheckResult result = check(R"(
local T = {}
T.x = 0
function T.method()
return 5
end
local a = T:method()
)");
auto it = std::find_if(result.errors.begin(), result.errors.end(), [](const TypeError& e) {
return nullptr != get<FunctionDoesNotTakeSelf>(e);
});
REQUIRE(it != result.errors.end());
}
TEST_CASE_FIXTURE(Fixture, "open_table_unification_2")
{
CheckResult result = check(R"(
local a = {}
a.x = 99
function a:method()
return self.y
end
a:method()
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeError& err = result.errors[0];
MissingProperties* error = get<MissingProperties>(err);
REQUIRE_MESSAGE(error != nullptr, "Expected MissingProperties but got " << toString(err));
REQUIRE(error->properties.size() == 1);
CHECK_EQ("y", error->properties[0]);
// TODO(rblanckaert): Revist when we can bind self at function creation time
// CHECK_EQ(err.location, Location(Position{5, 19}, Position{5, 25}));
CHECK_EQ(err.location, Location(Position{7, 8}, Position{7, 9}));
}
TEST_CASE_FIXTURE(Fixture, "open_table_unification_3")
{
CheckResult result = check(R"(
function id(x)
return x
end
function foo(o)
id(o.bar)
id(o.baz)
end
)");
TypeId fooType = requireType("foo");
const FunctionType* fooFn = get<FunctionType>(fooType);
REQUIRE(fooFn != nullptr);
std::vector<TypeId> fooArgs = flatten(fooFn->argTypes).first;
REQUIRE_EQ(1, fooArgs.size());
TypeId arg0 = fooArgs[0];
const TableType* arg0Table = get<TableType>(follow(arg0));
REQUIRE(arg0Table != nullptr);
CHECK(arg0Table->props.count("bar"));
CHECK(arg0Table->props.count("baz"));
}
TEST_CASE_FIXTURE(Fixture, "table_param_width_subtyping_1")
{
CheckResult result = check(R"(
function foo(o)
local a = o.x
local b = o.y
return o
end
foo({x=55, y=nil, w=3.14159})
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "table_param_width_subtyping_2")
{
CheckResult result = check(R"(
--!strict
function foo(o)
local a = o.bar
local b = o.baz
end
foo({bar='bar'})
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
MissingProperties* error = get<MissingProperties>(result.errors[0]);
REQUIRE_MESSAGE(error != nullptr, "Expected MissingProperties but got " << toString(result.errors[0]));
REQUIRE(error->properties.size() == 1);
CHECK_EQ("baz", error->properties[0]);
}
TEST_CASE_FIXTURE(Fixture, "table_param_width_subtyping_3")
{
CheckResult result = check(R"(
local T = {}
T.bar = 'hello'
function T:method()
local a = self.baz
end
T:method()
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeError& err = result.errors[0];
MissingProperties* error = get<MissingProperties>(err);
REQUIRE_MESSAGE(error != nullptr, "Expected MissingProperties but got " << toString(err));
REQUIRE(error->properties.size() == 1);
CHECK_EQ("baz", error->properties[0]);
// TODO(rblanckaert): Revist when we can bind self at function creation time
/*
CHECK_EQ(err->location,
(Location{ Position{4, 22}, Position{4, 30} })
);
*/
CHECK_EQ(err.location, (Location{Position{6, 8}, Position{6, 9}}));
}
TEST_CASE_FIXTURE(Fixture, "table_unification_4")
{
CheckResult result = check(R"(
function foo(o)
if o.prop then
return o
else
return {prop=false}
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "ok_to_add_property_to_free_table")
{
CheckResult result = check(R"(
function fn(d)
d:Method()
d.prop = true
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
dumpErrors(result);
}
TEST_CASE_FIXTURE(Fixture, "okay_to_add_property_to_unsealed_tables_by_assignment")
{
CheckResult result = check(R"(
--!strict
local t = { u = {} }
t = { u = { p = 37 } }
t = { u = { q = "hi" } }
local x = t.u.p
local y = t.u.q
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number?", toString(requireType("x")));
CHECK_EQ("string?", toString(requireType("y")));
}
TEST_CASE_FIXTURE(Fixture, "okay_to_add_property_to_unsealed_tables_by_function_call")
{
CheckResult result = check(R"(
--!strict
function get(x) return x.opts["MYOPT"] end
function set(x,y) x.opts["MYOPT"] = y end
local t = { opts = {} }
set(t,37)
local x = get(t)
)");
if (FFlag::DebugLuauDeferredConstraintResolution)
{
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number", toString(requireType("x")));
}
else
{
LUAU_REQUIRE_ERRORS(result);
// CHECK_EQ("number?", toString(requireType("x")));
}
}
TEST_CASE_FIXTURE(Fixture, "width_subtyping")
{
CheckResult result = check(R"(
--!strict
function f(x : { q : number })
x.q = 8
end
local t : { q : number, r : string } = { q = 8, r = "hi" }
f(t)
local x : string = t.r
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "width_subtyping_needs_covariance")
{
CheckResult result = check(R"(
--!strict
function f(x : { p : { q : number }})
x.p = { q = 8, r = 5 }
end
local t : { p : { q : number, r : string } } = { p = { q = 8, r = "hi" } }
f(t) -- Shouldn't typecheck
local x : string = t.p.r -- x is 5
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "infer_array")
{
CheckResult result = check(R"(
local t = {}
t[1] = 'one'
t[2] = 'two'
)");
LUAU_REQUIRE_NO_ERRORS(result);
const TableType* ttv = get<TableType>(requireType("t"));
REQUIRE(ttv != nullptr);
REQUIRE(bool(ttv->indexer));
CHECK_EQ(*ttv->indexer->indexType, *builtinTypes->numberType);
CHECK_EQ(*ttv->indexer->indexResultType, *builtinTypes->stringType);
}
/* This is a bit weird.
* The type of buttonVector[i] is initially free, compared to a string with ==
* We can't actually use this to infer that buttonVector is {string}, and we
* also have a rule that forbids comparing unknown types with those that may have
* metatables.
*
* Due to a historical quirk, strings are exempt from this rule. Without this exemption,
* the test code here would fail to typecheck at the use of ==.
*/
TEST_CASE_FIXTURE(Fixture, "infer_array_2")
{
CheckResult result = check(R"(
local buttonVector = {}
function createButton( actionName, functionInfoTable )
local position = nil
for i = 1,#buttonVector do
if buttonVector[i] == "empty" then
position = i
break
end
end
return position
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "indexers_get_quantified_too")
{
CheckResult result = check(R"(
function swap(p)
local temp = p[0]
p[0] = p[1]
p[1] = temp
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
const FunctionType* ftv = get<FunctionType>(requireType("swap"));
REQUIRE(ftv != nullptr);
std::vector<TypeId> argVec = flatten(ftv->argTypes).first;
REQUIRE_EQ(1, argVec.size());
const TableType* ttv = get<TableType>(follow(argVec[0]));
REQUIRE(ttv != nullptr);
REQUIRE(bool(ttv->indexer));
const TableIndexer& indexer = *ttv->indexer;
REQUIRE("number" == toString(indexer.indexType));
TypeId indexResultType = follow(indexer.indexResultType);
REQUIRE_MESSAGE(get<GenericType>(indexResultType), "Expected generic but got " << toString(indexResultType));
}
TEST_CASE_FIXTURE(Fixture, "indexers_quantification_2")
{
CheckResult result = check(R"(
function mergesort(arr)
local p = arr[0]
return arr
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
const FunctionType* ftv = get<FunctionType>(requireType("mergesort"));
REQUIRE(ftv != nullptr);
std::vector<TypeId> argVec = flatten(ftv->argTypes).first;
REQUIRE_EQ(1, argVec.size());
const TableType* argType = get<TableType>(follow(argVec[0]));
REQUIRE(argType != nullptr);
std::vector<TypeId> retVec = flatten(ftv->retTypes).first;
const TableType* retType = get<TableType>(follow(retVec[0]));
REQUIRE(retType != nullptr);
CHECK_EQ(argType->state, retType->state);
REQUIRE_EQ(*argVec[0], *retVec[0]);
}
TEST_CASE_FIXTURE(Fixture, "infer_indexer_from_array_like_table")
{
CheckResult result = check(R"(
local t = {"one", "two", "three"}
)");
LUAU_REQUIRE_NO_ERRORS(result);
const TableType* ttv = get<TableType>(requireType("t"));
REQUIRE(ttv != nullptr);
REQUIRE(bool(ttv->indexer));
const TableIndexer& indexer = *ttv->indexer;
CHECK_EQ(*builtinTypes->numberType, *indexer.indexType);
CHECK_EQ(*builtinTypes->stringType, *indexer.indexResultType);
}
TEST_CASE_FIXTURE(Fixture, "infer_indexer_from_value_property_in_literal")
{
CheckResult result = check(R"(
function Symbol(n)
return { __name=n }
end
function f()
return {
[Symbol("hello")] = true,
x = 0,
y = 0
}
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
const FunctionType* fType = get<FunctionType>(requireType("f"));
REQUIRE(fType != nullptr);
auto retType_ = first(fType->retTypes);
REQUIRE(bool(retType_));
auto retType = get<TableType>(follow(*retType_));
REQUIRE(retType != nullptr);
CHECK(bool(retType->indexer));
const TableIndexer& indexer = *retType->indexer;
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("{ __name: string }", toString(indexer.indexType));
else
CHECK_EQ("{| __name: string |}", toString(indexer.indexType));
}
TEST_CASE_FIXTURE(Fixture, "infer_indexer_from_its_variable_type_and_unifiable")
{
CheckResult result = check(R"(
local t1: { [string]: string } = {}
local t2 = { "bar" }
t2 = t1
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm != nullptr);
TypeId t2Ty = requireType("t2");
const TableType* tTy = get<TableType>(t2Ty);
REQUIRE_MESSAGE(tTy != nullptr, "Expected a table but got " << toString(t2Ty));
REQUIRE(tTy->indexer);
CHECK_EQ(*builtinTypes->numberType, *tTy->indexer->indexType);
CHECK_EQ(*builtinTypes->stringType, *tTy->indexer->indexResultType);
}
TEST_CASE_FIXTURE(Fixture, "indexer_mismatch")
{
CheckResult result = check(R"(
local t1: { [string]: string } = {}
local t2: { [number]: number } = {}
t2 = t1
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeId t1 = requireType("t1");
TypeId t2 = requireType("t2");
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm != nullptr);
CHECK(toString(tm->wantedType) == "{number}");
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK(toString(tm->givenType) == "{ [string]: string }");
else
CHECK(toString(tm->givenType) == "{| [string]: string |}");
CHECK_NE(*t1, *t2);
}
TEST_CASE_FIXTURE(Fixture, "infer_indexer_from_its_function_return_type")
{
CheckResult result = check(R"(
local function f(): { [number]: string }
return {}
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "infer_indexer_for_left_unsealed_table_from_right_hand_table_with_indexer")
{
CheckResult result = check(R"(
local function f(): { [number]: string } return {} end
local t = {}
t = f()
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "sealed_table_value_can_infer_an_indexer")
{
CheckResult result = check(R"(
local t: { a: string, [number]: string } = { a = "foo" }
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "array_factory_function")
{
CheckResult result = check(R"(
function empty() return {} end
local array: {string} = empty()
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "sealed_table_indexers_must_unify")
{
CheckResult result = check(R"(
function f(a: {number}): {string}
return a
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_MESSAGE(nullptr != get<TypeMismatch>(result.errors[0]), "Expected a TypeMismatch but got " << result.errors[0]);
}
TEST_CASE_FIXTURE(Fixture, "indexer_on_sealed_table_must_unify_with_free_table")
{
CheckResult result = check(R"(
function F(t): {number}
t[4] = "hi"
return t
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "infer_type_when_indexing_from_a_table_indexer")
{
CheckResult result = check(R"(
function f(t: {string})
return t[1]
end
local s = f({})
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*builtinTypes->stringType, *requireType("s"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "indexing_from_a_table_should_prefer_properties_when_possible")
{
CheckResult result = check(R"(
function f(): { a: string, [string]: number }
error("e")
end
local t = f()
local a1 = t.a
local a2 = t["a"]
local b1 = t.b
local b2 = t["b"]
local some_indirection_variable = "foo"
local c = t[some_indirection_variable]
local d = t[1]
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(*builtinTypes->stringType, *requireType("a1"));
CHECK_EQ(*builtinTypes->stringType, *requireType("a2"));
CHECK_EQ(*builtinTypes->numberType, *requireType("b1"));
CHECK_EQ(*builtinTypes->numberType, *requireType("b2"));
CHECK_EQ(*builtinTypes->numberType, *requireType("c"));
CHECK_MESSAGE(nullptr != get<TypeMismatch>(result.errors[0]), "Expected a TypeMismatch but got " << result.errors[0]);
}
TEST_CASE_FIXTURE(Fixture, "any_when_indexing_into_an_unsealed_table_with_no_indexer_in_nonstrict_mode")
{
CheckResult result = check(R"(
--!nonstrict
local constants = {
key1 = "value1",
key2 = "value2"
}
local function getKey()
return "key1"
end
local k1 = constants[getKey()]
)");
CHECK("any" == toString(requireType("k1")));
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "disallow_indexing_into_an_unsealed_table_with_no_indexer_in_strict_mode")
{
CheckResult result = check(R"(
local constants = {
key1 = "value1",
key2 = "value2"
}
function getConstant(key)
return constants[key]
end
local k1 = getConstant("key1")
)");
CHECK("any" == toString(requireType("k1")));
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "assigning_to_an_unsealed_table_with_string_literal_should_infer_new_properties_over_indexer")
{
CheckResult result = check(R"(
local t = {}
t["a"] = "foo"
local a = t.a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK("string" == toString(*builtinTypes->stringType));
TypeId tType = requireType("t");
TableType* tableType = getMutable<TableType>(tType);
REQUIRE_MESSAGE(tableType != nullptr, "Expected a table but got " << toString(tType, {true}));
REQUIRE(tableType->indexer == std::nullopt);
REQUIRE(0 != tableType->props.count("a"));
TypeId propertyA = tableType->props["a"].type();
REQUIRE(propertyA != nullptr);
CHECK_EQ(*builtinTypes->stringType, *propertyA);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "oop_indexer_works")
{
CheckResult result = check(R"(
local clazz = {}
clazz.__index = clazz
function clazz:speak()
return "hi"
end
function clazz.new()
return setmetatable({}, clazz)
end
local me = clazz.new()
local words = me:speak()
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*builtinTypes->stringType, *requireType("words"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "indexer_table")
{
CheckResult result = check(R"(
local clazz = {a="hello"}
local instanace = setmetatable({}, {__index=clazz})
local b = instanace.a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*builtinTypes->stringType, *requireType("b"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "indexer_fn")
{
CheckResult result = check(R"(
local instanace = setmetatable({}, {__index=function() return 10 end})
local b = instanace.somemethodwedonthave
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*builtinTypes->numberType, *requireType("b"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "meta_add")
{
// Note: meta_add_inferred and this unit test are currently the same exact thing.
// We'll want to change this one in particular when we add real syntax for metatables.
CheckResult result = check(R"(
local a = setmetatable({}, {__add = function(l, r) return l end})
type Vector = typeof(a)
local b:Vector
local c = a + b
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(follow(requireType("a")), follow(requireType("c")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "meta_add_inferred")
{
CheckResult result = check(R"(
local a = {}
setmetatable(a, {__add=function(a,b) return b end} )
local c = a + a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*requireType("a"), *requireType("c"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "meta_add_both_ways")
{
ScopedFastFlag sff{FFlag::DebugLuauDeferredConstraintResolution, false};
CheckResult result = check(R"(
type VectorMt = { __add: (Vector, number) -> Vector }
local vectorMt: VectorMt
type Vector = typeof(setmetatable({}, vectorMt))
local a: Vector
local b = a + 2
local c = 2 + a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Vector", toString(requireType("a")));
CHECK_EQ(*requireType("a"), *requireType("b"));
CHECK_EQ(*requireType("a"), *requireType("c"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "meta_add_both_ways_lti")
{
ScopedFastFlag sff{FFlag::DebugLuauDeferredConstraintResolution, true};
CheckResult result = check(R"(
local vectorMt = {}
function vectorMt.__add(self: Vector, other: number)
return self
end
type Vector = typeof(setmetatable({}, vectorMt))
local a: Vector = setmetatable({}, vectorMt)
local b = a + 2
local c = 2 + a
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Vector", toString(requireType("a")));
CHECK_EQ(*requireType("a"), *requireType("b"));
CHECK_EQ(*requireType("a"), *requireType("c"));
}
// This test exposed a bug where we let go of the "seen" stack while unifying table types
// As a result, type inference crashed with a stack overflow.
TEST_CASE_FIXTURE(BuiltinsFixture, "unification_of_unions_in_a_self_referential_type")
{
CheckResult result = check(R"(
type A = {}
type AMT = { __mul: (A, A | number) -> A }
local a: A
local amt: AMT
setmetatable(a, amt)
type B = {}
type BMT = { __mul: (B, A | B | number) -> A }
local b: B
local bmt: BMT
setmetatable(b, bmt)
a = b
)");
LUAU_REQUIRE_NO_ERRORS(result);
const MetatableType* amtv = get<MetatableType>(requireType("a"));
REQUIRE(amtv);
CHECK_EQ(follow(amtv->metatable), follow(requireType("amt")));
const MetatableType* bmtv = get<MetatableType>(requireType("b"));
REQUIRE(bmtv);
CHECK_EQ(follow(bmtv->metatable), follow(requireType("bmt")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "oop_polymorphic")
{
CheckResult result = check(R"(
local animal = {}
animal.__index = animal
function animal:isAlive() return true end
function animal:speed() return 10 end
local pelican = {}
setmetatable(pelican, animal)
pelican.__index = pelican
function pelican:movement() return "fly" end
function pelican:speed() return 30 end
function pelican.new(name)
local s = {}
setmetatable(s, pelican)
s.name = name
return s
end
local scoops = pelican.new("scoops")
local alive = scoops:isAlive()
local at = scoops.isAlive
local movement = scoops:movement()
local name = scoops.name
local speed = scoops:speed()
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ(*builtinTypes->booleanType, *requireType("alive"));
CHECK_EQ(*builtinTypes->stringType, *requireType("movement"));
CHECK_EQ(*builtinTypes->stringType, *requireType("name"));
CHECK_EQ(*builtinTypes->numberType, *requireType("speed"));
}
TEST_CASE_FIXTURE(Fixture, "user_defined_table_types_are_named")
{
CheckResult result = check(R"(
type Vector3 = {x: number, y: number}
local v: Vector3 = {x = 5, y = 7}
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("Vector3", toString(requireType("v")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "result_is_always_any_if_lhs_is_any")
{
CheckResult result = check(R"(
type Vector3MT = {
__add: (Vector3MT, Vector3MT) -> Vector3MT,
__mul: (Vector3MT, Vector3MT|number) -> Vector3MT
}
local Vector3: {new: (number?, number?, number?) -> Vector3MT}
local Vector3MT: Vector3MT
setmetatable(Vector3, Vector3MT)
type CFrameMT = {
__mul: (CFrameMT, Vector3MT|CFrameMT) -> Vector3MT|CFrameMT
}
local CFrame: {
Angles:(number, number, number) -> CFrameMT
}
local CFrameMT: CFrameMT
setmetatable(CFrame, CFrameMT)
local n: any
local a = (n + Vector3.new(0, 1.5, 0)) * CFrame.Angles(0, math.pi/2, 0)
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("any", toString(requireType("a")));
}
TEST_CASE_FIXTURE(Fixture, "result_is_bool_for_equality_operators_if_lhs_is_any")
{
CheckResult result = check(R"(
function f(): (any, number)
return 5, 7
end
local a: any, b: number = f()
local c = a < b
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("boolean", toString(requireType("c")));
}
TEST_CASE_FIXTURE(Fixture, "inequality_operators_imply_exactly_matching_types")
{
CheckResult result = check(R"(
function abs(n)
if n < 0 then
return -n
else
return n
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(number) -> number", toString(requireType("abs")));
}
TEST_CASE_FIXTURE(Fixture, "nice_error_when_trying_to_fetch_property_of_boolean")
{
CheckResult result = check(R"(
local a = true
local b = a.some_prop
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Type 'boolean' does not have key 'some_prop'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "defining_a_method_for_a_builtin_sealed_table_must_fail")
{
CheckResult result = check(R"(
function string.m() end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "defining_a_self_method_for_a_builtin_sealed_table_must_fail")
{
CheckResult result = check(R"(
function string:m() end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "defining_a_method_for_a_local_sealed_table_must_fail")
{
CheckResult result = check(R"(
function mkt() return {x = 1} end
local t = mkt()
function t.m() end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "defining_a_self_method_for_a_local_sealed_table_must_fail")
{
CheckResult result = check(R"(
function mkt() return {x = 1} end
local t = mkt()
function t:m() end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(Fixture, "defining_a_method_for_a_local_unsealed_table_is_ok")
{
CheckResult result = check(R"(
local t = {x = 1}
function t.m() end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "defining_a_self_method_for_a_local_unsealed_table_is_ok")
{
CheckResult result = check(R"(
local t = {x = 1}
function t:m() end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
// This unit test could be flaky if the fix has regressed.
TEST_CASE_FIXTURE(Fixture, "pass_incompatible_union_to_a_generic_table_without_crashing")
{
CheckResult result = check(R"(
-- must be in this specific order, and with (roughly) those exact properties!
type A = {x: number, [any]: any} | {}
function f(t)
t.y = 1
end
function g(a: A)
f(a)
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK(get<TypeMismatch>(result.errors[0]));
}
// This unit test could be flaky if the fix has regressed.
TEST_CASE_FIXTURE(Fixture, "passing_compatible_unions_to_a_generic_table_without_crashing")
{
CheckResult result = check(R"(
type A = {x: number, y: number, [any]: any} | {y: number}
function f(t)
t.y = 1
end
function g(a: A)
f(a)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "found_like_key_in_table_function_call")
{
CheckResult result = check(R"(
local t = {}
function t.Foo() end
t.fOo()
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeError te = result.errors[0];
UnknownPropButFoundLikeProp* error = get<UnknownPropButFoundLikeProp>(te);
REQUIRE(error);
TypeId t = requireType("t");
CHECK_EQ(*t, *error->table);
CHECK_EQ("fOo", error->key);
auto candidates = error->candidates;
CHECK_EQ(1, candidates.size());
CHECK(candidates.find("Foo") != candidates.end());
CHECK_EQ(toString(te), "Key 'fOo' not found in table 't'. Did you mean 'Foo'?");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "found_like_key_in_table_property_access")
{
CheckResult result = check(R"(
local t = {X = 1}
print(t.x)
)");
REQUIRE_EQ(result.errors.size(), 1);
TypeError te = result.errors[0];
UnknownPropButFoundLikeProp* error = get<UnknownPropButFoundLikeProp>(te);
REQUIRE(error);
TypeId t = requireType("t");
CHECK_EQ(*t, *error->table);
CHECK_EQ("x", error->key);
auto candidates = error->candidates;
CHECK_EQ(1, candidates.size());
CHECK(candidates.find("X") != candidates.end());
CHECK_EQ(toString(te), "Key 'x' not found in table 't'. Did you mean 'X'?");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "found_multiple_like_keys")
{
CheckResult result = check(R"(
local t = {Foo = 1, foO = 2}
print(t.foo)
)");
REQUIRE_EQ(result.errors.size(), 1);
TypeError te = result.errors[0];
UnknownPropButFoundLikeProp* error = get<UnknownPropButFoundLikeProp>(te);
REQUIRE(error);
TypeId t = requireType("t");
CHECK_EQ(*t, *error->table);
CHECK_EQ("foo", error->key);
auto candidates = error->candidates;
CHECK_EQ(2, candidates.size());
CHECK(candidates.find("Foo") != candidates.end());
CHECK(candidates.find("foO") != candidates.end());
CHECK_EQ(toString(te), "Key 'foo' not found in table 't'. Did you mean one of 'Foo', 'foO'?");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "dont_suggest_exact_match_keys")
{
CheckResult result = check(R"(
local t = {}
t.foO = 1
print(t.Foo)
t.Foo = 2
)");
REQUIRE_EQ(result.errors.size(), 1);
TypeError te = result.errors[0];
UnknownPropButFoundLikeProp* error = get<UnknownPropButFoundLikeProp>(te);
REQUIRE(error);
TypeId t = requireType("t");
CHECK_EQ(*t, *error->table);
CHECK_EQ("Foo", error->key);
auto candidates = error->candidates;
CHECK_EQ(1, candidates.size());
CHECK(candidates.find("foO") != candidates.end());
CHECK(candidates.find("Foo") == candidates.end());
CHECK_EQ(toString(te), "Key 'Foo' not found in table 't'. Did you mean 'foO'?");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "getmetatable_returns_pointer_to_metatable")
{
CheckResult result = check(R"(
local t = {x = 1}
local mt = {__index = {y = 2}}
setmetatable(t, mt)
local returnedMT = getmetatable(t)
)");
CHECK_EQ(*requireType("mt"), *requireType("returnedMT"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "metatable_mismatch_should_fail")
{
CheckResult result = check(R"(
local t1 = {x = 1}
local mt1 = {__index = {y = 2}}
setmetatable(t1, mt1)
local t2 = {x = 1}
local mt2 = {__index = function() return nil end}
setmetatable(t2, mt2)
t1 = t2
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK_EQ(*tm->wantedType, *requireType("t1"));
CHECK_EQ(*tm->givenType, *requireType("t2"));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "property_lookup_through_tabletypevar_metatable")
{
CheckResult result = check(R"(
local t = {x = 1}
local mt = {__index = {y = 2}}
setmetatable(t, mt)
print(t.x)
print(t.y)
print(t.z)
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
UnknownProperty* up = get<UnknownProperty>(result.errors[0]);
REQUIRE_MESSAGE(up, result.errors[0].data);
CHECK_EQ(up->key, "z");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "missing_metatable_for_sealed_tables_do_not_get_inferred")
{
CheckResult result = check(R"(
local t = {x = 1}
local a = {x = 1}
local b = {__index = {y = 2}}
setmetatable(a, b)
t = a
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeId a = requireType("a");
TypeId t = requireType("t");
CHECK_NE(*a, *t);
TypeError te = result.errors[0];
TypeMismatch* tm = get<TypeMismatch>(te);
REQUIRE(tm);
CHECK_EQ(tm->wantedType, t);
CHECK_EQ(tm->givenType, a);
const MetatableType* aTy = get<MetatableType>(a);
REQUIRE(aTy);
const TableType* tTy = get<TableType>(t);
REQUIRE(tTy);
}
// Could be flaky if the fix has regressed.
TEST_CASE_FIXTURE(Fixture, "right_table_missing_key")
{
CheckResult result = check(R"(
function _(...)
end
local l7 = not _,function(l0)
_ += _((_) or {function(...)
end,["z"]=_,} or {},(function(l43,...)
end))
_ += 0 < {}
end
repeat
until _
local l0 = n4,_((_) or {} or {[30976]=_,},({}))
)");
CHECK_GE(result.errors.size(), 0);
}
// Could be flaky if the fix has regressed.
TEST_CASE_FIXTURE(Fixture, "right_table_missing_key2")
{
CheckResult result = check(R"(
function f(t: {}): { [string]: string, a: string }
return t
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
MissingProperties* mp = get<MissingProperties>(result.errors[0]);
REQUIRE_MESSAGE(mp, "Expected MissingProperties but got " << toString(result.errors[0]));
CHECK_EQ(mp->context, MissingProperties::Missing);
REQUIRE_EQ(1, mp->properties.size());
CHECK_EQ(mp->properties[0], "a");
CHECK_EQ("{| [string]: string, a: string |}", toString(mp->superType));
CHECK_EQ("{| |}", toString(mp->subType));
}
TEST_CASE_FIXTURE(Fixture, "casting_unsealed_tables_with_props_into_table_with_indexer")
{
ScopedFastFlag sff{FFlag::LuauAlwaysCommitInferencesOfFunctionCalls, true};
CheckResult result = check(R"(
type StringToStringMap = { [string]: string }
local rt: StringToStringMap = { ["foo"] = 1 }
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
ToStringOptions o{/* exhaustive= */ true};
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK_EQ("{| [string]: string |}", toString(tm->wantedType, o));
// Should t now have an indexer?
// It would if the assignment to rt was correctly typed.
CHECK_EQ("{ [string]: string, foo: number }", toString(tm->givenType, o));
}
TEST_CASE_FIXTURE(Fixture, "casting_sealed_tables_with_props_into_table_with_indexer")
{
CheckResult result = check(R"(
type StringToStringMap = { [string]: string }
function mkrt() return { ["foo"] = 1 } end
local rt: StringToStringMap = mkrt()
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
ToStringOptions o{/* exhaustive= */ true};
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK_EQ("{ [string]: string }", toString(tm->wantedType, o));
CHECK_EQ("{ foo: number }", toString(tm->givenType, o));
}
else
{
CHECK_EQ("{| [string]: string |}", toString(tm->wantedType, o));
CHECK_EQ("{| foo: number |}", toString(tm->givenType, o));
}
}
TEST_CASE_FIXTURE(Fixture, "casting_tables_with_props_into_table_with_indexer2")
{
CheckResult result = check(R"(
local function foo(a: {[string]: number, a: string}) end
foo({ a = "" })
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "casting_tables_with_props_into_table_with_indexer3")
{
ScopedFastFlag sff{FFlag::LuauAlwaysCommitInferencesOfFunctionCalls, true};
CheckResult result = check(R"(
local function foo(a: {[string]: number, a: string}) end
foo({ a = 1 })
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
ToStringOptions o{/* exhaustive= */ true};
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK_EQ("{| [string]: number, a: string |}", toString(tm->wantedType, o));
CHECK_EQ("{ [string]: number, a: number }", toString(tm->givenType, o));
}
TEST_CASE_FIXTURE(Fixture, "casting_tables_with_props_into_table_with_indexer4")
{
CheckResult result = check(R"(
local function foo(a: {[string]: number, a: string}, i: string)
return a[i]
end
local hi: number = foo({ a = "hi" }, "a") -- shouldn't typecheck since at runtime hi is "hi"
)");
if (FFlag::DebugLuauDeferredConstraintResolution)
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK(toString(result.errors[0]) == "Type 'number' could not be converted into 'string' in an invariant context");
}
else
{
// This typechecks but shouldn't
LUAU_REQUIRE_NO_ERRORS(result);
}
}
TEST_CASE_FIXTURE(Fixture, "table_subtyping_with_missing_props_dont_report_multiple_errors")
{
CheckResult result = check(R"(
function f(vec1: {x: number}): {x: number, y: number, z: number}
return vec1
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK_EQ("Type pack '{ x: number }' could not be converted into '{ x: number, y: number, z: number }';"
" at [0], { x: number } is not a subtype of { x: number, y: number, z: number }",
toString(result.errors[0]));
}
else
{
MissingProperties* mp = get<MissingProperties>(result.errors[0]);
REQUIRE_MESSAGE(mp, result.errors[0]);
CHECK_EQ(mp->context, MissingProperties::Missing);
REQUIRE_EQ(2, mp->properties.size());
CHECK_EQ(mp->properties[0], "y");
CHECK_EQ(mp->properties[1], "z");
CHECK_EQ("{| x: number, y: number, z: number |}", toString(mp->superType));
CHECK_EQ("{| x: number |}", toString(mp->subType));
}
}
TEST_CASE_FIXTURE(Fixture, "table_subtyping_with_missing_props_dont_report_multiple_errors2")
{
CheckResult result = check(R"(
type DumbMixedTable = {[number]: number, x: number}
local t: DumbMixedTable = {"fail"}
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
MissingProperties* mp = get<MissingProperties>(result.errors[1]);
REQUIRE(mp);
CHECK_EQ(mp->context, MissingProperties::Missing);
REQUIRE_EQ(1, mp->properties.size());
CHECK_EQ(mp->properties[0], "x");
}
TEST_CASE_FIXTURE(Fixture, "table_subtyping_with_extra_props_dont_report_multiple_errors")
{
CheckResult result = check(R"(
function mkvec3() return {x = 1, y = 2, z = 3} end
function mkvec1() return {x = 1} end
local vec3: {{x: number, y: number, z: number}} = {mkvec3()}
local vec1: {{x: number}} = {mkvec1()}
vec1 = vec3
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK_EQ("vec1", toString(tm->wantedType));
CHECK_EQ("vec3", toString(tm->givenType));
}
else
{
CHECK_EQ("{{| x: number |}}", toString(tm->wantedType));
CHECK_EQ("{{| x: number, y: number, z: number |}}", toString(tm->givenType));
}
}
TEST_CASE_FIXTURE(Fixture, "table_subtyping_with_extra_props_is_ok")
{
CheckResult result = check(R"(
local vec3 = {x = 1, y = 2, z = 3}
local vec1 = {x = 1}
vec1 = vec3
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "type_mismatch_on_massive_table_is_cut_short")
{
ScopedFastInt sfis{FInt::LuauTableTypeMaximumStringifierLength, 40};
CheckResult result = check(R"(
local t
t = {}
t.a = 1
t.b = 1
t.c = 1
t.d = 1
t.e = 1
t.f = 1
t = 1
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK("{ a: number, b: number, c: number, d: number, e: number, ... 1 more ... }" == toString(requireType("t")));
CHECK_EQ("number", toString(tm->givenType));
CHECK_EQ("Type 'number' could not be converted into '{ a: number, b: number, c: number, d: number, e: number, ... 1 more ... }'",
toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "ok_to_set_nil_even_on_non_lvalue_base_expr")
{
CheckResult result = check(R"(
local function f(): { [string]: number }
return { ["foo"] = 1 }
end
f()["foo"] = nil
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "ok_to_provide_a_subtype_during_construction")
{
CheckResult result = check(R"(
local a: string | number = 1
local t = {a, 1}
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("{number | string}", toString(requireType("t"), {/*exhaustive*/ true}));
}
TEST_CASE_FIXTURE(Fixture, "reasonable_error_when_adding_a_nonexistent_property_to_an_array_like_table")
{
CheckResult result = check(R"(
--!strict
function mkA() return {"value"} end
local A = mkA()
A.B = "Hello"
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
UnknownProperty* up = get<UnknownProperty>(result.errors[0]);
REQUIRE(up != nullptr);
CHECK_EQ("B", up->key);
}
TEST_CASE_FIXTURE(Fixture, "shorter_array_types_actually_work")
{
CheckResult result = check(R"(
--!strict
local A: {string | number}
)");
LUAU_REQUIRE_ERROR_COUNT(0, result);
CHECK_EQ("{number | string}", toString(requireType("A")));
}
TEST_CASE_FIXTURE(Fixture, "only_ascribe_synthetic_names_at_module_scope")
{
CheckResult result = check(R"(
--!strict
local TopLevel = {}
local foo
for i = 1, 10 do
local SubScope = { 1, 2, 3 }
foo = SubScope
end
)");
LUAU_REQUIRE_ERROR_COUNT(0, result);
CHECK_EQ("TopLevel", toString(requireType("TopLevel")));
CHECK_EQ("{number}", toString(requireType("foo")));
}
TEST_CASE_FIXTURE(Fixture, "hide_table_error_properties")
{
CheckResult result = check(R"(
--!strict
local function f()
local function mkt() return { x = 1 } end
local t = mkt()
function t.a() end
function t.b() end
return t
end
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK_EQ("Cannot add property 'a' to table '{ x: number }'", toString(result.errors[0]));
CHECK_EQ("Cannot add property 'b' to table '{ x: number }'", toString(result.errors[1]));
}
else
{
CHECK_EQ("Cannot add property 'a' to table '{| x: number |}'", toString(result.errors[0]));
CHECK_EQ("Cannot add property 'b' to table '{| x: number |}'", toString(result.errors[1]));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "builtin_table_names")
{
CheckResult result = check(R"(
os.h = 2
string.k = 3
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ("Cannot add property 'h' to table 'typeof(os)'", toString(result.errors[0]));
CHECK_EQ("Cannot add property 'k' to table 'typeof(string)'", toString(result.errors[1]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "persistent_sealed_table_is_immutable")
{
CheckResult result = check(R"(
--!nonstrict
function os:bad() end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Cannot add property 'bad' to table 'typeof(os)'", toString(result.errors[0]));
const TableType* osType = get<TableType>(requireType("os"));
REQUIRE(osType != nullptr);
CHECK(osType->props.find("bad") == osType->props.end());
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_list")
{
CheckResult result = check(R"(
type Table = {
a: number,
b: number?
}
local Test: {Table} = {
{ a = 1 },
{ a = 2, b = 3 }
}
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_general")
{
CheckResult result = check(R"(
type Table = {
a: number,
b: number?
}
local Test: {Table} = {
[2] = { a = 1 },
[5] = { a = 2, b = 3 }
}
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_inner_index")
{
CheckResult result = check(R"(
type Table = {
a: number,
b: number?
}
local Test: {{Table}} = {{
{ a = 1 },
{ a = 2, b = 3 }
},{
{ a = 3 },
{ a = 4, b = 3 }
}}
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_inner_prop")
{
CheckResult result = check(R"(
type Table = {
a: number,
b: number?
}
local Test: {{x: Table, y: Table}} = {{
x = { a = 1 },
y = { a = 2, b = 3 }
},{
x = { a = 3 },
y = { a = 4 }
}}
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_union_assignment")
{
CheckResult result = check(R"(
type Foo = {x: number | string}
local foos: {Foo} = {
{x = 1234567},
{x = "hello"},
}
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "quantifying_a_bound_var_works")
{
CheckResult result = check(R"(
local clazz = {}
clazz.__index = clazz
function clazz:speak()
return "hi"
end
function clazz.new()
return setmetatable({}, clazz)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
TypeId ty = requireType("clazz");
TableType* ttv = getMutable<TableType>(ty);
REQUIRE_MESSAGE(ttv, "Expected a table but got " << toString(ty, {true}));
REQUIRE(ttv->props.count("new"));
Property& prop = ttv->props["new"];
REQUIRE(prop.type());
const FunctionType* ftv = get<FunctionType>(follow(prop.type()));
REQUIRE(ftv);
const TypePack* res = get<TypePack>(follow(ftv->retTypes));
REQUIRE(res);
REQUIRE(res->head.size() == 1);
const MetatableType* mtv = get<MetatableType>(follow(res->head[0]));
REQUIRE(mtv);
ttv = getMutable<TableType>(follow(mtv->table));
REQUIRE(ttv);
REQUIRE_EQ(ttv->state, TableState::Sealed);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "less_exponential_blowup_please")
{
ScopedFastFlag sff{FFlag::DebugLuauSharedSelf, true};
CheckResult result = check(R"(
--!strict
local Foo = setmetatable({}, {})
Foo.__index = Foo
function Foo.new()
local self = setmetatable({}, Foo)
return self:constructor() or self
end
function Foo:constructor() end
function Foo:create()
local foo = Foo.new()
foo:First()
foo:Second()
foo:Third()
return foo
end
function Foo:First() end
function Foo:Second() end
function Foo:Third() end
local newData = Foo:create()
newData:First()
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_union_in_call")
{
CheckResult result = check(R"(
local function foo(l: {{x: number | string}}) end
foo({
{x = 1234567},
{x = "hello"},
})
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_union_in_call_tail")
{
CheckResult result = check(R"(
type Foo = {x: number | string}
local function foo(l: {Foo}, ...: {Foo}) end
foo({{x = 1234567}, {x = "hello"}}, {{x = 1234567}, {x = "hello"}}, {{x = 1234567}, {x = "hello"}})
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "common_table_element_union_in_prop")
{
CheckResult result = check(R"(
type Foo = {x: number | string}
local t: { a: {Foo}, b: number } = {
a = {
{x = 1234567},
{x = "hello"},
},
b = 5
}
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
// It's unsound to instantiate tables containing generic methods,
// since mutating properties means table properties should be invariant.
TEST_CASE_FIXTURE(Fixture, "invariant_table_properties_means_instantiating_tables_in_assignment_is_unsound")
{
CheckResult result = check(R"(
--!strict
local t = {}
function t.m(x) return x end
local a : string = t.m("hi")
local b : number = t.m(5)
local u : { m : (number)->number } = t -- This shouldn't typecheck
u.m = function(x) return 1+x end
local c : string = t.m("hi")
)");
// TODO: test behavior is wrong with LuauInstantiateInSubtyping until we can re-enable the covariant requirement for instantiation in subtyping
if (FFlag::LuauInstantiateInSubtyping)
LUAU_REQUIRE_NO_ERRORS(result);
else
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_insert_should_cope_with_optional_properties_in_nonstrict")
{
CheckResult result = check(R"(
--!nonstrict
local buttons = {}
table.insert(buttons, { a = 1 })
table.insert(buttons, { a = 2, b = true })
table.insert(buttons, { a = 3 })
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_insert_should_cope_with_optional_properties_in_strict")
{
CheckResult result = check(R"(
--!strict
local buttons = {}
table.insert(buttons, { a = 1 })
table.insert(buttons, { a = 2, b = true })
table.insert(buttons, { a = 3 })
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "error_detailed_prop")
{
CheckResult result = check(R"(
type A = { x: number, y: number }
type B = { x: number, y: string }
local a: A = { x = 123, y = 456 }
local b: B = a
)");
LUAU_REQUIRE_ERRORS(result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK(toString(result.errors.at(0)) == R"(Type 'a' could not be converted into 'B'; at [read "y"], number is not exactly string)");
else
{
const std::string expected = R"(Type 'A' could not be converted into 'B'
caused by:
Property 'y' is not compatible.
Type 'number' could not be converted into 'string' in an invariant context)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "error_detailed_prop_nested")
{
CheckResult result = check(R"(
type AS = { x: number, y: number }
type BS = { x: number, y: string }
type A = { a: boolean, b: AS }
type B = { a: boolean, b: BS }
local a: A = { a = false, b = { x = 123, y = 456 } }
local b: B = a
)");
LUAU_REQUIRE_ERRORS(result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK(toString(result.errors.at(0)) == R"(Type 'a' could not be converted into 'B'; at [read "b"][read "y"], number is not exactly string)");
else
{
const std::string expected = R"(Type 'A' could not be converted into 'B'
caused by:
Property 'b' is not compatible.
Type 'AS' could not be converted into 'BS'
caused by:
Property 'y' is not compatible.
Type 'number' could not be converted into 'string' in an invariant context)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "error_detailed_metatable_prop")
{
CheckResult result = check(R"(
local a1 = setmetatable({ x = 2, y = 3 }, { __call = function(s) end });
local b1 = setmetatable({ x = 2, y = "hello" }, { __call = function(s) end });
local c1: typeof(a1) = b1
local a2 = setmetatable({ x = 2, y = 3 }, { __call = function(s) end });
local b2 = setmetatable({ x = 2, y = 4 }, { __call = function(s, t) end });
local c2: typeof(a2) = b2
)");
const std::string expected1 = R"(Type 'b1' could not be converted into 'a1'
caused by:
Type
'{ x: number, y: string }'
could not be converted into
'{ x: number, y: number }'
caused by:
Property 'y' is not compatible.
Type 'string' could not be converted into 'number' in an invariant context)";
const std::string expected2 = R"(Type 'b2' could not be converted into 'a2'
caused by:
Type
'{ __call: <a, b>(a, b) -> () }'
could not be converted into
'{ __call: <a>(a) -> () }'
caused by:
Property '__call' is not compatible.
Type
'<a, b>(a, b) -> ()'
could not be converted into
'<a>(a) -> ()'; different number of generic type parameters)";
const std::string expected3 = R"(Type 'b2' could not be converted into 'a2'
caused by:
Type
'{ __call: <a, b>(a, b) -> () }'
could not be converted into
'{ __call: <a>(a) -> () }'
caused by:
Property '__call' is not compatible.
Type
'<a, b>(a, b) -> ()'
could not be converted into
'<a>(a) -> ()'; different number of generic type parameters)";
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(expected1, toString(result.errors[0]));
if (FFlag::LuauInstantiateInSubtyping)
{
CHECK_EQ(expected2, toString(result.errors[1]));
}
else
{
std::string expected3 = R"(Type 'b2' could not be converted into 'a2'
caused by:
Type
'{ __call: (a, b) -> () }'
could not be converted into
'{ __call: <a>(a) -> () }'
caused by:
Property '__call' is not compatible.
Type
'(a, b) -> ()'
could not be converted into
'<a>(a) -> ()'; different number of generic type parameters)";
CHECK_EQ(expected3, toString(result.errors[1]));
}
}
TEST_CASE_FIXTURE(Fixture, "error_detailed_indexer_key")
{
CheckResult result = check(R"(
type A = { [number]: string }
type B = { [string]: string }
local a: A = { 'a', 'b' }
local b: B = a
)");
LUAU_REQUIRE_ERRORS(result);
const std::string expected = R"(Type 'A' could not be converted into 'B'
caused by:
Property '[indexer key]' is not compatible.
Type 'number' could not be converted into 'string' in an invariant context)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "error_detailed_indexer_value")
{
CheckResult result = check(R"(
type A = { [number]: number }
type B = { [number]: string }
local a: A = { 1, 2, 3 }
local b: B = a
)");
LUAU_REQUIRE_ERRORS(result);
const std::string expected = R"(Type 'A' could not be converted into 'B'
caused by:
Property '[indexer value]' is not compatible.
Type 'number' could not be converted into 'string' in an invariant context)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "explicitly_typed_table")
{
CheckResult result = check(R"(
--!strict
type Super = { x : number }
type Sub = { x : number, y: number }
type HasSuper = { p : Super }
type HasSub = { p : Sub }
local a: HasSuper = { p = { x = 5, y = 7 }}
a.p = { x = 9 }
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "explicitly_typed_table_error")
{
CheckResult result = check(R"(
--!strict
type Super = { x : number }
type Sub = { x : number, y: number }
type HasSuper = { p : Super }
type HasSub = { p : Sub }
local tmp = { p = { x = 5, y = 7 }}
local a: HasSuper = tmp
a.p = { x = 9 }
-- needs to be an error because
local y: number = tmp.p.y
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type 'tmp' could not be converted into 'HasSuper'
caused by:
Property 'p' is not compatible.
Table type '{ x: number, y: number }' not compatible with type 'Super' because the former has extra field 'y')";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "explicitly_typed_table_with_indexer")
{
CheckResult result = check(R"(
--!strict
type Super = { x : number }
type Sub = { x : number, y: number }
type HasSuper = { [string] : Super }
type HasSub = { [string] : Sub }
local a: HasSuper = { p = { x = 5, y = 7 }}
a.p = { x = 9 }
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "recursive_metatable_type_call")
{
CheckResult result = check(R"(
local b
b = setmetatable({}, {__call = b})
b()
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(toString(result.errors[0]), R"(Cannot call non-function t1 where t1 = { @metatable { __call: t1 }, { } })");
}
TEST_CASE_FIXTURE(Fixture, "table_subtyping_shouldn't_add_optional_properties_to_sealed_tables")
{
CheckResult result = check(R"(
--!strict
local function setNumber(t: { p: number? }, x:number) t.p = x end
local function getString(t: { p: string? }):string return t.p or "" end
-- This shouldn't type-check!
local function oh(x:number): string
local t: {} = {}
setNumber(t, x)
return getString(t)
end
local s: string = oh(37)
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "top_table_type")
{
CheckResult result = check(R"(
--!strict
type Table = { [any] : any }
type HasTable = { p: Table? }
type HasHasTable = { p: HasTable? }
local t : Table = { p = 5 }
local u : HasTable = { p = { p = 5 } }
local v : HasHasTable = { p = { p = { p = 5 } } }
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "length_operator_union")
{
CheckResult result = check(R"(
local x: {number} | {string}
local y = #x
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "length_operator_intersection")
{
CheckResult result = check(R"(
local x: {number} & {z:string} -- mixed tables are evil
local y = #x
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "length_operator_non_table_union")
{
CheckResult result = check(R"(
local x: {number} | any | string
local y = #x
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "length_operator_union_errors")
{
CheckResult result = check(R"(
local x: {number} | number | string
local y = #x
)");
if (FFlag::DebugLuauDeferredConstraintResolution)
LUAU_REQUIRE_ERROR_COUNT(2, result);
else
LUAU_REQUIRE_ERROR_COUNT(1, result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "dont_hang_when_trying_to_look_up_in_cyclic_metatable_index")
{
// t :: t1 where t1 = {metatable {__index: t1, __tostring: (t1) -> string}}
CheckResult result = check(R"(
local mt = {}
local t = setmetatable({}, mt)
mt.__index = t
function mt:__tostring()
return t.p
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Type 't' does not have key 'p'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "give_up_after_one_metatable_index_look_up")
{
CheckResult result = check(R"(
local data = { x = 5 }
local t1 = setmetatable({}, { __index = data })
local t2 = setmetatable({}, t1) -- note: must be t1, not a new table
local x1 = t1.x -- ok
local x2 = t2.x -- nope
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Type 't2' does not have key 'x'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "confusing_indexing")
{
CheckResult result = check(R"(
type T = {} & {p: number | string}
local function f(t: T)
return t.p
end
local foo = f({p = "string"})
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("number | string", toString(requireType("foo")));
}
TEST_CASE_FIXTURE(Fixture, "pass_a_union_of_tables_to_a_function_that_requires_a_table")
{
ScopedFastFlag sff{FFlag::LuauAlwaysCommitInferencesOfFunctionCalls, true};
CheckResult result = check(R"(
local a: {x: number, y: number, [any]: any} | {y: number}
function f(t)
t.y = 1
return t
end
local b = f(a)
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::DebugLuauDeferredConstraintResolution)
REQUIRE_EQ("{| [any]: any, x: number, y: number |} | {| y: number |}", toString(requireType("b")));
else
REQUIRE_EQ("{- y: number -}", toString(requireType("b")));
}
TEST_CASE_FIXTURE(Fixture, "pass_a_union_of_tables_to_a_function_that_requires_a_table_2")
{
ScopedFastFlag sff{FFlag::LuauAlwaysCommitInferencesOfFunctionCalls, true};
CheckResult result = check(R"(
local a: {y: number} | {x: number, y: number, [any]: any}
function f(t)
t.y = 1
return t
end
local b = f(a)
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::DebugLuauDeferredConstraintResolution)
REQUIRE_EQ("{| [any]: any, x: number, y: number |} | {| y: number |}", toString(requireType("b")));
else
REQUIRE_EQ("{- y: number -}", toString(requireType("b")));
}
TEST_CASE_FIXTURE(Fixture, "unifying_tables_shouldnt_uaf1")
{
CheckResult result = check(R"(
-- This example produced a UAF at one point, caused by pointers to table types becoming
-- invalidated by child unifiers. (Calling log.concat can cause pointers to become invalid.)
type _Entry = {
a: number,
middle: (self: _Entry) -> (),
z: number
}
export type AnyEntry = _Entry
local Entry = {}
Entry.__index = Entry
function Entry:dispose()
self:middle()
forgetChildren(self) -- unify free with sealed AnyEntry
end
function forgetChildren(parent: AnyEntry)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "unifying_tables_shouldnt_uaf2")
{
CheckResult result = check(R"(
-- Another example that UAFd, this time found by fuzzing.
local _
do
_._ *= (_[{n0=_[{[{[_]=_,}]=_,}],}])[_]
_ = (_.n0)
end
_._ *= (_[false])[_]
_ = (_.cos)
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cannot_call_tables")
{
CheckResult result = check("local foo = {} foo()");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK(get<CannotCallNonFunction>(result.errors[0]) != nullptr);
}
TEST_CASE_FIXTURE(Fixture, "table_length")
{
CheckResult result = check(R"(
local t = {}
local s = #t
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK(nullptr != get<TableType>(requireType("t")));
CHECK_EQ(*builtinTypes->numberType, *requireType("s"));
}
TEST_CASE_FIXTURE(Fixture, "nil_assign_doesnt_hit_indexer")
{
CheckResult result = check("local a = {} a[0] = 7 a[0] = nil");
LUAU_REQUIRE_ERROR_COUNT(0, result);
}
TEST_CASE_FIXTURE(Fixture, "wrong_assign_does_hit_indexer")
{
CheckResult result = check(R"(
local a = {}
a[0] = 7
a[0] = 't'
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK((Location{Position{3, 15}, Position{3, 18}}) == result.errors[0].location);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
CHECK(tm->wantedType == builtinTypes->numberType);
CHECK(tm->givenType == builtinTypes->stringType);
}
TEST_CASE_FIXTURE(Fixture, "nil_assign_doesnt_hit_no_indexer")
{
CheckResult result = check(R"(
local a = {a=1, b=2}
a['a'] = nil
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(result.errors[0], (TypeError{Location{Position{2, 17}, Position{2, 20}}, TypeMismatch{
builtinTypes->numberType,
builtinTypes->nilType,
}}));
}
TEST_CASE_FIXTURE(Fixture, "free_rhs_table_can_also_be_bound")
{
check(R"(
local o
local v = o:i()
function g(u)
v = u
end
o:f(g)
o:h()
o:h()
)");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_unifies_into_map")
{
CheckResult result = check(R"(
local Instance: any
local UDim2: any
function Create(instanceType)
return function(data)
local obj = Instance.new(instanceType)
for k, v in pairs(data) do
if type(k) == 'number' then
--v.Parent = obj
else
obj[k] = v
end
end
return obj
end
end
local topbarShadow = Create'ImageLabel'{
Name = "TopBarShadow";
Size = UDim2.new(1, 0, 0, 3);
Position = UDim2.new(0, 0, 1, 0);
Image = "rbxasset://textures/ui/TopBar/dropshadow.png";
BackgroundTransparency = 1;
Active = false;
Visible = false;
};
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "tables_get_names_from_their_locals")
{
CheckResult result = check(R"(
local T = {}
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("T", toString(requireType("T")));
}
TEST_CASE_FIXTURE(Fixture, "generalize_table_argument")
{
CheckResult result = check(R"(
function foo(arr)
local work = {}
for i = 1, #arr do
work[i] = arr[i]
end
return arr
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
dumpErrors(result);
const FunctionType* fooType = get<FunctionType>(requireType("foo"));
REQUIRE(fooType);
std::optional<TypeId> fooArg1 = first(fooType->argTypes);
REQUIRE(fooArg1);
const TableType* fooArg1Table = get<TableType>(follow(*fooArg1));
REQUIRE(fooArg1Table);
CHECK_EQ(fooArg1Table->state, TableState::Generic);
}
/*
* This test case exposed an oversight in the treatment of free tables.
* Free tables, like free Types, need to record the scope depth where they were created so that
* we do not erroneously let-generalize them when they are used in a nested lambda.
*
* For more information about let-generalization, see <http://okmij.org/ftp/ML/generalization.html>
*
* The important idea here is that the return type of Counter.new is a table with some metatable.
* That metatable *must* be the same Type as the type of Counter. If it is a copy (produced by
* the generalization process), then it loses the knowledge that its metatable will have an :incr()
* method.
*/
TEST_CASE_FIXTURE(BuiltinsFixture, "dont_quantify_table_that_belongs_to_outer_scope")
{
CheckResult result = check(R"(
local Counter = {}
Counter.__index = Counter
function Counter.new()
local self = setmetatable({count=0}, Counter)
return self
end
function Counter:incr()
self.count = 1
return self.count
end
local self = Counter.new()
print(self:incr())
)");
LUAU_REQUIRE_NO_ERRORS(result);
TableType* counterType = getMutable<TableType>(requireType("Counter"));
REQUIRE(counterType);
REQUIRE(counterType->props.count("new"));
const FunctionType* newType = get<FunctionType>(follow(counterType->props["new"].type()));
REQUIRE(newType);
std::optional<TypeId> newRetType = *first(newType->retTypes);
REQUIRE(newRetType);
const MetatableType* newRet = get<MetatableType>(follow(*newRetType));
REQUIRE(newRet);
const TableType* newRetMeta = get<TableType>(follow(newRet->metatable));
REQUIRE(newRetMeta);
CHECK(newRetMeta->props.count("incr"));
CHECK_EQ(follow(newRet->metatable), follow(requireType("Counter")));
}
// TODO: CLI-39624
TEST_CASE_FIXTURE(BuiltinsFixture, "instantiate_tables_at_scope_level")
{
CheckResult result = check(R"(
--!strict
local Option = {}
Option.__index = Option
function Option.Is(obj)
return (type(obj) == "table" and getmetatable(obj) == Option)
end
return Option
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "inferring_crazy_table_should_also_be_quick")
{
CheckResult result = check(R"(
--!strict
function f(U)
U(w:s(an):c()():c():U(s):c():c():U(s):c():U(s):cU()):c():U(s):c():U(s):c():c():U(s):c():U(s):cU()
end
)");
ModulePtr module = getMainModule();
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_GE(500, module->internalTypes.types.size());
else
CHECK_GE(100, module->internalTypes.types.size());
}
TEST_CASE_FIXTURE(Fixture, "MixedPropertiesAndIndexers")
{
CheckResult result = check(R"(
local x = {}
x.a = "a"
x[0] = true
x.b = 37
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "setmetatable_cant_be_used_to_mutate_global_types")
{
{
Fixture fix;
// inherit env from parent fixture checker
fix.frontend.globals.globalScope = frontend.globals.globalScope;
fix.check(R"(
--!nonstrict
type MT = typeof(setmetatable)
function wtf(arg: {MT}): typeof(table)
arg = wtf(arg)
end
)");
}
// validate sharedEnv post-typecheck; valuable for debugging some typeck crashes but slows fuzzing down
// note: it's important for typeck to be destroyed at this point!
{
for (auto& p : frontend.globals.globalScope->bindings)
{
toString(p.second.typeId); // toString walks the entire type, making sure ASAN catches access to destroyed type arenas
}
}
}
TEST_CASE_FIXTURE(Fixture, "evil_table_unification")
{
// this code re-infers the type of _ while processing fields of _, which can cause use-after-free
check(R"(
--!nonstrict
_ = ...
_:table(_,string)[_:gsub(_,...,n0)],_,_:gsub(_,string)[""],_:split(_,...,table)._,n0 = nil
do end
)");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "dont_crash_when_setmetatable_does_not_produce_a_metatabletypevar")
{
CheckResult result = check("local x = setmetatable({})");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Argument count mismatch. Function 'setmetatable' expects 2 arguments, but only 1 is specified", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "instantiate_table_cloning")
{
CheckResult result = check(R"(
--!nonstrict
local l0:any,l61:t0<t32> = _,math
while _ do
_()
end
function _():t0<t0>
end
type t0<t32> = any
)");
std::optional<TypeId> ty = requireType("math");
REQUIRE(ty);
const TableType* ttv = get<TableType>(*ty);
REQUIRE(ttv);
CHECK(ttv->instantiatedTypeParams.empty());
}
TEST_CASE_FIXTURE(BuiltinsFixture, "instantiate_table_cloning_2")
{
CheckResult result = check(R"(
type X<T> = T
type K = X<typeof(math)>
)");
LUAU_REQUIRE_NO_ERRORS(result);
std::optional<TypeId> ty = requireType("math");
REQUIRE(ty);
const TableType* ttv = get<TableType>(*ty);
REQUIRE(ttv);
CHECK(ttv->instantiatedTypeParams.empty());
}
TEST_CASE_FIXTURE(Fixture, "instantiate_table_cloning_3")
{
CheckResult result = check(R"(
type X<T> = T
local a = {}
a.x = 4
local b: X<typeof(a)>
a.y = 5
local c: X<typeof(a)>
c = b
)");
LUAU_REQUIRE_NO_ERRORS(result);
std::optional<TypeId> ty = requireType("a");
REQUIRE(ty);
const TableType* ttv = get<TableType>(*ty);
REQUIRE(ttv);
CHECK(ttv->instantiatedTypeParams.empty());
}
TEST_CASE_FIXTURE(Fixture, "table_indexing_error_location")
{
CheckResult result = check(R"(
local foo = {42}
local bar: number?
local baz = foo[bar]
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(result.errors[0].location, Location{Position{3, 16}, Position{3, 19}});
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_call_metamethod_basic")
{
if (!FFlag::DebugLuauDeferredConstraintResolution)
return;
CheckResult result = check(R"(
local a = setmetatable({
a = 1,
}, {
__call = function(self, b: number)
return self.a * b
end,
})
local foo = a(12)
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK(requireType("foo") == builtinTypes->numberType);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_call_metamethod_must_be_callable")
{
CheckResult result = check(R"(
local a = setmetatable({}, {
__call = 123,
})
local foo = a()
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK("Cannot call non-function { @metatable { __call: number }, { } }" == toString(result.errors[0]));
}
else
{
TypeError e{
Location{{5, 20}, {5, 21}},
CannotCallNonFunction{builtinTypes->numberType},
};
CHECK(result.errors[0] == e);
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_call_metamethod_generic")
{
CheckResult result = check(R"(
local a = setmetatable({}, {
__call = function<T>(self, b: T)
return b
end,
})
local foo = a(12)
local bar = a("bar")
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK(requireType("foo") == builtinTypes->numberType);
CHECK(requireType("bar") == builtinTypes->stringType);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_simple_call")
{
CheckResult result = check(R"(
local a = setmetatable({ x = 2 }, {
__call = function(self)
return (self.x :: number) * 2 -- should work without annotation in the future
end
})
local b = a()
local c = a(2) -- too many arguments
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Argument count mismatch. Function 'a' expects 1 argument, but 2 are specified", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "access_index_metamethod_that_returns_variadic")
{
CheckResult result = check(R"(
type Foo = {x: string}
local t = {}
setmetatable(t, {
__index = function(x: string): ...Foo
return {x = x}
end
})
local foo = t.bar
)");
LUAU_REQUIRE_NO_ERRORS(result);
ToStringOptions o;
o.exhaustive = true;
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("{ x: string }", toString(requireType("foo"), o));
else
CHECK_EQ("{| x: string |}", toString(requireType("foo"), o));
}
TEST_CASE_FIXTURE(Fixture, "dont_invalidate_the_properties_iterator_of_free_table_when_rolled_back")
{
fileResolver.source["Module/Backend/Types"] = R"(
export type Fiber = {
return_: Fiber?
}
return {}
)";
fileResolver.source["Module/Backend"] = R"(
local Types = require(script.Types)
type Fiber = Types.Fiber
type ReactRenderer = { findFiberByHostInstance: () -> Fiber? }
local function attach(renderer): ()
local function getPrimaryFiber(fiber)
local alternate = fiber.alternate
return fiber
end
local function getFiberIDForNative()
local fiber = renderer.findFiberByHostInstance()
fiber = fiber.return_
return getPrimaryFiber(fiber)
end
end
function culprit(renderer: ReactRenderer): ()
attach(renderer)
end
return culprit
)";
CheckResult result = frontend.check("Module/Backend");
}
TEST_CASE_FIXTURE(Fixture, "checked_prop_too_early")
{
CheckResult result = check(R"(
local t: {x: number?}? = {x = nil}
local u = t.x and t or 5
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Value of type '{| x: number? |}?' could be nil", toString(result.errors[0]));
CHECK_EQ("number | {| x: number? |}", toString(requireType("u")));
}
TEST_CASE_FIXTURE(Fixture, "accidentally_checked_prop_in_opposite_branch")
{
CheckResult result = check(R"(
local t: {x: number?}? = {x = nil}
local u = t and t.x == 5 or t.x == 31337
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("Value of type '{ x: number? }?' could be nil", toString(result.errors[0]));
else
CHECK_EQ("Value of type '{| x: number? |}?' could be nil", toString(result.errors[0]));
CHECK_EQ("boolean", toString(requireType("u")));
}
/*
* We had an issue where part of the type of pairs() was an unsealed table.
* This test depends on FFlagDebugLuauFreezeArena to trigger it.
*/
TEST_CASE_FIXTURE(Fixture, "pairs_parameters_are_not_unsealed_tables")
{
check(R"(
function _(l0:{n0:any})
_ = pairs
end
)");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "table_function_check_use_after_free")
{
CheckResult result = check(R"(
local t = {}
function t.x(value)
for k,v in pairs(t) do end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
/*
* When we add new properties to an unsealed table, we should do a level check and promote the property type to be at
* the level of the table.
*/
TEST_CASE_FIXTURE(Fixture, "inferred_properties_of_a_table_should_start_with_the_same_TypeLevel_of_that_table")
{
CheckResult result = check(R"(
--!strict
local T = {}
local function f(prop)
T[1] = {
prop = prop,
}
end
local function g()
local l = T[1].prop
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
// The real bug here was that we weren't always uncondionally typechecking a trailing return statement last.
TEST_CASE_FIXTURE(BuiltinsFixture, "dont_leak_free_table_props")
{
CheckResult result = check(R"(
local function a(state)
print(state.blah)
end
local function b(state) -- The bug was that we inferred state: {blah: any, gwar: any}
print(state.gwar)
end
return function()
return function(state)
a(state)
b(state)
end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("<a>({+ blah: a +}) -> ()", toString(requireType("a")));
CHECK_EQ("<a>({+ gwar: a +}) -> ()", toString(requireType("b")));
CHECK_EQ("() -> <a, b>({+ blah: a, gwar: b +}) -> ()", toString(getMainModule()->returnType));
}
TEST_CASE_FIXTURE(Fixture, "inferred_return_type_of_free_table")
{
ScopedFastFlag sff[] = {
// {FFlag::LuauLowerBoundsCalculation, true},
{FFlag::DebugLuauSharedSelf, true},
};
check(R"(
function Base64FileReader(data)
local reader = {}
local index: number
function reader:PeekByte()
return data:byte(index)
end
function reader:Byte()
return data:byte(index - 1)
end
return reader
end
)");
CHECK_EQ("<a, b...>(t1) -> {| Byte: (a) -> (b...), PeekByte: (a) -> (b...) |} where t1 = {+ byte: (t1, number) -> (b...) +}",
toString(requireType("Base64FileReader")));
}
TEST_CASE_FIXTURE(Fixture, "mixed_tables_with_implicit_numbered_keys")
{
CheckResult result = check(R"(
local t: { [string]: number } = { 5, 6, 7 }
)");
LUAU_REQUIRE_ERROR_COUNT(3, result);
CHECK_EQ("Type 'number' could not be converted into 'string'", toString(result.errors[0]));
CHECK_EQ("Type 'number' could not be converted into 'string'", toString(result.errors[1]));
CHECK_EQ("Type 'number' could not be converted into 'string'", toString(result.errors[2]));
}
TEST_CASE_FIXTURE(Fixture, "shared_selfs")
{
ScopedFastFlag sff{FFlag::DebugLuauSharedSelf, true};
CheckResult result = check(R"(
local t = {}
t.x = 5
function t:m1() return self.x end
function t:m2() return self.y end
return t
)");
LUAU_REQUIRE_NO_ERRORS(result);
ToStringOptions opts;
opts.exhaustive = true;
CHECK_EQ("{| m1: <a, b>({+ x: a, y: b +}) -> a, m2: <a, b>({+ x: a, y: b +}) -> b, x: number |}", toString(requireType("t"), opts));
}
TEST_CASE_FIXTURE(Fixture, "shared_selfs_from_free_param")
{
ScopedFastFlag sff{FFlag::DebugLuauSharedSelf, true};
CheckResult result = check(R"(
local function f(t)
function t:m1() return self.x end
function t:m2() return self.y end
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("<a, b>({+ m1: ({+ x: a, y: b +}) -> a, m2: ({+ x: a, y: b +}) -> b +}) -> ()", toString(requireType("f")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "shared_selfs_through_metatables")
{
ScopedFastFlag sff{FFlag::DebugLuauSharedSelf, true};
CheckResult result = check(R"(
local t = {}
t.__index = t
setmetatable({}, t)
function t:m1() return self.x end
function t:m2() return self.y end
return t
)");
LUAU_REQUIRE_NO_ERRORS(result);
ToStringOptions opts;
opts.exhaustive = true;
CHECK_EQ(
toString(requireType("t"), opts), "t1 where t1 = {| __index: t1, m1: <a, b>({+ x: a, y: b +}) -> a, m2: <a, b>({+ x: a, y: b +}) -> b |}");
}
TEST_CASE_FIXTURE(Fixture, "expected_indexer_value_type_extra")
{
CheckResult result = check(R"(
type X = { { x: boolean?, y: boolean? } }
local l1: {[string]: X} = { key = { { x = true }, { y = true } } }
local l2: {[any]: X} = { key = { { x = true }, { y = true } } }
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "expected_indexer_value_type_extra_2")
{
CheckResult result = check(R"(
type X = {[any]: string | boolean}
local x: X = { key = "str" }
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "expected_indexer_from_table_union")
{
LUAU_REQUIRE_NO_ERRORS(check(R"(local a: {[string]: {number | string}} = {a = {2, 's'}})"));
LUAU_REQUIRE_NO_ERRORS(check(R"(local a: {[string]: {number | string}}? = {a = {2, 's'}})"));
LUAU_REQUIRE_NO_ERRORS(check(R"(local a: {[string]: {[string]: {string?}}?} = {["a"] = {["b"] = {"a", "b"}}})"));
}
TEST_CASE_FIXTURE(Fixture, "prop_access_on_key_whose_types_mismatches")
{
CheckResult result = check(R"(
local t: {number} = {}
local x = t.x
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ("Key 'x' not found in table '{number}'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "prop_access_on_unions_of_indexers_where_key_whose_types_mismatches")
{
CheckResult result = check(R"(
local t: { [number]: number } | { [boolean]: number } = {}
local u = t.x
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("Type '{ [boolean]: number } | {number}' does not have key 'x'", toString(result.errors[0]));
else
CHECK_EQ("Type '{number} | {| [boolean]: number |}' does not have key 'x'", toString(result.errors[0]));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "quantify_metatables_of_metatables_of_table")
{
ScopedFastFlag sff[]{
{FFlag::DebugLuauSharedSelf, true},
};
CheckResult result = check(R"(
local T = {}
function T:m()
return self.x, self.y
end
function T:n()
end
local U = setmetatable({}, {__index = T})
local V = setmetatable({}, {__index = U})
return V
)");
LUAU_REQUIRE_NO_ERRORS(result);
ToStringOptions opts;
opts.exhaustive = true;
CHECK_EQ(toString(requireType("V"), opts), "{ @metatable { __index: { @metatable { __index: {| m: <a, b>({+ x: a, y: b +}) -> (a, b), n: <a, "
"b>({+ x: a, y: b +}) -> () |} }, { } } }, { } }");
}
TEST_CASE_FIXTURE(Fixture, "quantify_even_that_table_was_never_exported_at_all")
{
ScopedFastFlag sff{FFlag::DebugLuauSharedSelf, true};
CheckResult result = check(R"(
local T = {}
function T:m()
return self.x
end
function T:n()
return self.y
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
ToStringOptions opts;
opts.exhaustive = true;
CHECK_EQ("{| m: <a, b>({+ x: a, y: b +}) -> a, n: <a, b>({+ x: a, y: b +}) -> b |}", toString(requireType("T"), opts));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "leaking_bad_metatable_errors")
{
CheckResult result = check(R"(
local a = setmetatable({}, 1)
local b = a.x
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ("Metatable was not a table", toString(result.errors[0]));
CHECK_EQ("Type 'a' does not have key 'x'", toString(result.errors[1]));
}
TEST_CASE_FIXTURE(Fixture, "scalar_is_a_subtype_of_a_compatible_polymorphic_shape_type")
{
CheckResult result = check(R"(
local function f(s)
return s:lower()
end
f("foo" :: string)
f("bar" :: "bar")
f("baz" :: "bar" | "baz")
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "scalar_is_not_a_subtype_of_a_compatible_polymorphic_shape_type")
{
ScopedFastFlag sff[] = {
{FFlag::LuauAlwaysCommitInferencesOfFunctionCalls, true},
};
CheckResult result = check(R"(
local function f(s)
return s:absolutely_no_scalar_has_this_method()
end
f("foo" :: string)
f("bar" :: "bar")
f("baz" :: "bar" | "baz")
)");
LUAU_REQUIRE_ERROR_COUNT(3, result);
const std::string expected1 =
R"(Type 'string' could not be converted into 't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}'
caused by:
The former's metatable does not satisfy the requirements.
Table type 'typeof(string)' not compatible with type 't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}' because the former is missing field 'absolutely_no_scalar_has_this_method')";
CHECK_EQ(expected1, toString(result.errors[0]));
const std::string expected2 =
R"(Type '"bar"' could not be converted into 't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}'
caused by:
The former's metatable does not satisfy the requirements.
Table type 'typeof(string)' not compatible with type 't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}' because the former is missing field 'absolutely_no_scalar_has_this_method')";
CHECK_EQ(expected2, toString(result.errors[1]));
const std::string expected3 = R"(Type
'"bar" | "baz"'
could not be converted into
't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}'
caused by:
Not all union options are compatible.
Type '"bar"' could not be converted into 't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}'
caused by:
The former's metatable does not satisfy the requirements.
Table type 'typeof(string)' not compatible with type 't1 where t1 = {- absolutely_no_scalar_has_this_method: (t1) -> (a...) -}' because the former is missing field 'absolutely_no_scalar_has_this_method')";
CHECK_EQ(expected3, toString(result.errors[2]));
}
TEST_CASE_FIXTURE(Fixture, "a_free_shape_can_turn_into_a_scalar_if_it_is_compatible")
{
CheckResult result = check(R"(
local function f(s): string
local foo = s:lower()
return s
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(string) -> string", toString(requireType("f")));
}
TEST_CASE_FIXTURE(Fixture, "a_free_shape_cannot_turn_into_a_scalar_if_it_is_not_compatible")
{
CheckResult result = check(R"(
local function f(s): string
local foo = s:absolutely_no_scalar_has_this_method()
return s
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK(toString(result.errors.at(0)) ==
"Type pack 't1 where t1 = { absolutely_no_scalar_has_this_method: (t1) -> (unknown, a...) }' could not be converted into 'string'; at "
"[0], t1 where t1 = { absolutely_no_scalar_has_this_method: (t1) -> (unknown, a...) } is not a subtype of string");
else
{
const std::string expected =
R"(Type 't1 where t1 = {+ absolutely_no_scalar_has_this_method: (t1) -> (a, b...) +}' could not be converted into 'string'
caused by:
The former's metatable does not satisfy the requirements.
Table type 'typeof(string)' not compatible with type 't1 where t1 = {+ absolutely_no_scalar_has_this_method: (t1) -> (a, b...) +}' because the former is missing field 'absolutely_no_scalar_has_this_method')";
CHECK_EQ(expected, toString(result.errors[0]));
}
CHECK_EQ("<a, b...>(t1) -> string where t1 = {+ absolutely_no_scalar_has_this_method: (t1) -> (a, b...) +}", toString(requireType("f")));
}
TEST_CASE_FIXTURE(BuiltinsFixture, "a_free_shape_can_turn_into_a_scalar_directly")
{
CheckResult result = check(R"(
local function stringByteList(str)
local out = {}
for i = 1, #str do
table.insert(out, string.byte(str, i))
end
return table.concat(out, ",")
end
local x = stringByteList("xoo")
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "invariant_table_properties_means_instantiating_tables_in_call_is_unsound")
{
ScopedFastFlag sff[]{
{FFlag::LuauInstantiateInSubtyping, true},
};
CheckResult result = check(R"(
--!strict
local t = {}
function t.m(x) return x end
local a : string = t.m("hi")
local b : number = t.m(5)
function f(x : { m : (number)->number })
x.m = function(x) return 1+x end
end
f(t) -- This shouldn't typecheck
local c : string = t.m("hi")
)");
LUAU_REQUIRE_NO_ERRORS(result);
// TODO: test behavior is wrong until we can re-enable the covariant requirement for instantiation in subtyping
// LUAU_REQUIRE_ERRORS(result);
// CHECK_EQ(toString(result.errors[0]), R"(Type 't' could not be converted into '{| m: (number) -> number |}'
// caused by:
// Property 'm' is not compatible. Type '<a>(a) -> a' could not be converted into '(number) -> number'; different number of generic type
// parameters)");
// // this error message is not great since the underlying issue is that the context is invariant,
// and `(number) -> number` cannot be a subtype of `<a>(a) -> a`.
}
TEST_CASE_FIXTURE(BuiltinsFixture, "generic_table_instantiation_potential_regression")
{
CheckResult result = check(R"(
--!strict
function f(x)
x.p = 5
return x
end
local g : ({ p : number, q : string }) -> ({ p : number, r : boolean }) = f
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
MissingProperties* error = get<MissingProperties>(result.errors[0]);
REQUIRE(error != nullptr);
REQUIRE(error->properties.size() == 1);
CHECK_EQ("r", error->properties[0]);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "setmetatable_has_a_side_effect")
{
if (!FFlag::DebugLuauDeferredConstraintResolution)
return;
CheckResult result = check(R"(
local mt = {
__add = function(x, y)
return 123
end,
}
local foo = {}
setmetatable(foo, mt)
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK(toString(requireType("foo")) == "{ @metatable mt, foo }");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "tables_should_be_fully_populated")
{
CheckResult result = check(R"(
local t = {
x = 5 :: NonexistingTypeWhichEndsUpReturningAnErrorType,
y = 5
}
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
ToStringOptions opts;
opts.exhaustive = true;
CHECK_EQ("{ x: *error-type*, y: number }", toString(requireType("t"), opts));
}
TEST_CASE_FIXTURE(Fixture, "fuzz_table_indexer_unification_can_bound_owner_to_string")
{
CheckResult result = check(R"(
sin,_ = nil
_ = _[_.sin][_._][_][_]._
_[_] = _
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "fuzz_table_extra_prop_unification_can_bound_owner_to_string")
{
CheckResult result = check(R"(
l0,_ = nil
_ = _,_[_.n5]._[_][_][_]._
_._.foreach[_],_ = _[_],_._
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "fuzz_typelevel_promote_on_changed_table_type")
{
CheckResult result = check(R"(
_._,_ = nil
_ = _.foreach[_]._,_[_.n5]._[_.foreach][_][_]._
_ = _._
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "fuzz_table_unify_instantiated_table")
{
ScopedFastFlag sff[]{
{FFlag::LuauInstantiateInSubtyping, true},
};
CheckResult result = check(R"(
function _(...)
end
local function l0():typeof(_()()[_()()[_]])
end
return _[_()()[_]] <= _
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "fuzz_table_unify_instantiated_table_with_prop_realloc")
{
ScopedFastFlag sff[]{
{FFlag::LuauInstantiateInSubtyping, true},
};
CheckResult result = check(R"(
function _(l0,l0)
do
_ = _().n0
end
l0(_()._,_)
end
_(_,function(...)
end)
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "fuzz_table_unify_prop_realloc")
{
CheckResult result = check(R"(
n3,_ = nil
_ = _[""]._,_[l0][_._][{[_]=_,_=_,}][_G].number
_ = {_,}
)");
LUAU_REQUIRE_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "when_augmenting_an_unsealed_table_with_an_indexer_apply_the_correct_scope_to_the_indexer_type")
{
CheckResult result = check(R"(
local events = {}
local mockObserveEvent = function(_, key, callback)
events[key] = callback
end
events['FriendshipNotifications']({
EventArgs = {
UserId2 = '2'
},
Type = 'FriendshipDeclined'
})
)");
TypeId ty = follow(requireType("events"));
const TableType* tt = get<TableType>(ty);
REQUIRE_MESSAGE(tt, "Expected table but got " << toString(ty, {true}));
CHECK(tt->props.empty());
REQUIRE(tt->indexer);
CHECK("string" == toString(tt->indexer->indexType));
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "dont_extend_unsealed_tables_in_rvalue_position")
{
CheckResult result = check(R"(
local testDictionary = {
FruitName = "Lemon",
FruitColor = "Yellow",
Sour = true
}
local print: any
print(testDictionary[""])
)");
TypeId ty = follow(requireType("testDictionary"));
const TableType* ttv = get<TableType>(ty);
REQUIRE(ttv);
CHECK(0 == ttv->props.count(""));
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "extend_unsealed_table_with_metatable")
{
CheckResult result = check(R"(
local T = setmetatable({}, {
__call = function(_, name: string?)
end,
})
T.for_ = "for_"
return T
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "top_table_type_is_isomorphic_to_empty_sealed_table_type")
{
CheckResult result = check(R"(
local None = newproxy(true)
local mt = getmetatable(None)
mt.__tostring = function()
return "Object.None"
end
function assign(...)
for index = 1, select("#", ...) do
local rest = select(index, ...)
if rest ~= nil and typeof(rest) == "table" then
for key, value in pairs(rest) do
end
end
end
end
)");
}
TEST_CASE_FIXTURE(BuiltinsFixture, "luau-polyfill.Array.includes")
{
CheckResult result = check(R"(
type Array<T> = { [number]: T }
function indexOf<T>(array: Array<T>, searchElement: any, fromIndex: number?): number
return -1
end
return function<T>(array: Array<T>, searchElement: any, fromIndex: number?): boolean
return -1 ~= indexOf(array, searchElement, fromIndex)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "certain_properties_of_table_literal_arguments_can_be_covariant")
{
CheckResult result = check(R"(
function f(a: {[string]: string | {any} | nil })
return a
end
local x = f({
title = "Feature.VirtualEvents.EnableNotificationsModalTitle",
body = "Feature.VirtualEvents.EnableNotificationsModalBody",
notNow = "Feature.VirtualEvents.NotNowButton",
getNotified = "Feature.VirtualEvents.GetNotifiedButton",
})
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "subproperties_can_also_be_covariantly_tested")
{
CheckResult result = check(R"(
type T = {
[string]: {[string]: (string | number)?}
}
function f(t: T)
return t
end
local x = f({
subprop={x="hello"}
})
local y = f({
subprop={x=41}
})
local z = f({
subprop={}
})
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cyclic_shifted_tables")
{
CheckResult result = check(R"(
local function id<a>(x: a): a
return x
end
-- Remove name from cyclic table
local foo = id({})
foo.foo = id({})
foo.foo.foo = id({})
foo.foo.foo.foo = id({})
foo.foo.foo.foo.foo = foo
local almostFoo = id({})
almostFoo.foo = id({})
almostFoo.foo.foo = id({})
almostFoo.foo.foo.foo = id({})
almostFoo.foo.foo.foo.foo = almostFoo
-- Shift
almostFoo = almostFoo.foo.foo
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cli_84607_missing_prop_in_array_or_dict")
{
ScopedFastFlag sff{FFlag::LuauFixIndexerSubtypingOrdering, true};
CheckResult result = check(R"(
type Thing = { name: string, prop: boolean }
local arrayOfThings : {Thing} = {
{ name = "a" }
}
local dictOfThings : {[string]: Thing} = {
a = { name = "a" }
}
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
TypeError& err1 = result.errors[0];
MissingProperties* error1 = get<MissingProperties>(err1);
REQUIRE(error1);
REQUIRE(error1->properties.size() == 1);
CHECK_EQ("prop", error1->properties[0]);
TypeError& err2 = result.errors[1];
TypeMismatch* mismatch = get<TypeMismatch>(err2);
REQUIRE(mismatch);
MissingProperties* error2 = get<MissingProperties>(*mismatch->error);
REQUIRE(error2);
REQUIRE(error2->properties.size() == 1);
CHECK_EQ("prop", error2->properties[0]);
}
TEST_CASE_FIXTURE(Fixture, "simple_method_definition")
{
CheckResult result = check(R"(
local T = {}
function T:m()
return 5
end
return T
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ("{ m: (unknown) -> number }", toString(getMainModule()->returnType, ToStringOptions{true}));
else
CHECK_EQ("{| m: <a>(a) -> number |}", toString(getMainModule()->returnType, ToStringOptions{true}));
}
TEST_CASE_FIXTURE(Fixture, "identify_all_problematic_table_fields")
{
ScopedFastFlag sff_DebugLuauDeferredConstraintResolution{FFlag::DebugLuauDeferredConstraintResolution, true};
CheckResult result = check(R"(
type T = {
a: number,
b: string,
c: boolean,
}
local a: T = {
a = "foo",
b = false,
c = 123,
}
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
std::string expected = "Type 'a' could not be converted into 'T'; at [read \"a\"], string is not exactly number"
"\n\tat [read \"b\"], boolean is not exactly string"
"\n\tat [read \"c\"], number is not exactly boolean";
CHECK(toString(result.errors[0]) == expected);
}
TEST_CASE_FIXTURE(Fixture, "read_and_write_only_table_properties_are_unsupported")
{
ScopedFastFlag sff[] = {
{FFlag::LuauReadWritePropertySyntax, true},
{FFlag::DebugLuauDeferredConstraintResolution, false},
};
CheckResult result = check(R"(
type W = {read x: number}
type X = {write x: boolean}
type Y = {read ["prop"]: boolean}
type Z = {write ["prop"]: string}
)");
LUAU_REQUIRE_ERROR_COUNT(4, result);
CHECK("read keyword is illegal here" == toString(result.errors[0]));
CHECK(Location{{1, 18}, {1, 22}} == result.errors[0].location);
CHECK("write keyword is illegal here" == toString(result.errors[1]));
CHECK(Location{{2, 18}, {2, 23}} == result.errors[1].location);
CHECK("read keyword is illegal here" == toString(result.errors[2]));
CHECK(Location{{4, 18}, {4, 22}} == result.errors[2].location);
CHECK("write keyword is illegal here" == toString(result.errors[3]));
CHECK(Location{{5, 18}, {5, 23}} == result.errors[3].location);
}
TEST_CASE_FIXTURE(Fixture, "read_ond_write_only_indexers_are_unsupported")
{
ScopedFastFlag sff{FFlag::LuauReadWritePropertySyntax, true};
CheckResult result = check(R"(
type T = {read [string]: number}
type U = {write [string]: boolean}
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK("read keyword is illegal here" == toString(result.errors[0]));
CHECK(Location{{1, 18}, {1, 22}} == result.errors[0].location);
CHECK("write keyword is illegal here" == toString(result.errors[1]));
CHECK(Location{{2, 18}, {2, 23}} == result.errors[1].location);
}
TEST_CASE_FIXTURE(Fixture, "infer_write_property")
{
ScopedFastFlag sff{FFlag::DebugLuauDeferredConstraintResolution, true};
CheckResult result = check(R"(
function f(t)
t.y = 1
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK("({ y: number }) -> ()" == toString(requireType("f")));
}
TEST_CASE_FIXTURE(Fixture, "table_subtyping_error_suppression")
{
CheckResult result = check(R"(
function one(tbl: {x: any}) end
function two(tbl: {x: string}) one(tbl) end -- ok, string <: any and any <: string
function three(tbl: {x: any, y: string}) end
function four(tbl: {x: string, y: string}) three(tbl) end -- ok, string <: any, any <: string, string <: string
function five(tbl: {x: string, y: number}) three(tbl) end -- error, string <: any, any <: string, but number </: string
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
TypeMismatch* tm = get<TypeMismatch>(result.errors[0]);
REQUIRE(tm);
// the new solver reports specifically the inner mismatch, rather than the whole table
// honestly not sure which of these is a better developer experience.
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK_EQ(*tm->wantedType, *builtinTypes->stringType);
CHECK_EQ(*tm->givenType, *builtinTypes->numberType);
}
else
{
CHECK_EQ("{| x: any, y: string |}", toString(tm->wantedType));
CHECK_EQ("{| x: string, y: number |}", toString(tm->givenType));
}
}
TEST_CASE_FIXTURE(Fixture, "write_to_read_only_property")
{
ScopedFastFlag sff{FFlag::DebugLuauDeferredConstraintResolution, true};
CheckResult result = check(R"(
function f(t: {read x: number})
t.x = 5
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK("Property x of table '{ read x: number }' is read-only" == toString(result.errors[0]));
PropertyAccessViolation* pav = get<PropertyAccessViolation>(result.errors[0]);
REQUIRE(pav);
CHECK("{ read x: number }" == toString(pav->table, {true}));
CHECK("x" == pav->key);
CHECK(PropertyAccessViolation::CannotWrite == pav->context);
}
TEST_CASE_FIXTURE(Fixture, "write_to_unusually_named_read_only_property")
{
ScopedFastFlag sff{FFlag::DebugLuauDeferredConstraintResolution, true};
CheckResult result = check(R"(
function f(t: {read ["hello world"]: number})
t["hello world"] = 5
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK("Property \"hello world\" of table '{ read [\"hello world\"]: number }' is read-only" == toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "write_annotations_are_unsupported_even_with_the_new_solver")
{
ScopedFastFlag sff{FFlag::DebugLuauDeferredConstraintResolution, true};
CheckResult result = check(R"(
function f(t: {write foo: number})
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK("write keyword is illegal here" == toString(result.errors[0]));
CHECK(Location{{1, 23}, {1, 28}} == result.errors[0].location);
}
TEST_CASE_FIXTURE(Fixture, "read_and_write_only_table_properties_are_unsupported")
{
ScopedFastFlag sff[] = {
{FFlag::LuauReadWritePropertySyntax, true},
{FFlag::DebugLuauDeferredConstraintResolution, false}
};
CheckResult result = check(R"(
type W = {read x: number}
type X = {write x: boolean}
type Y = {read ["prop"]: boolean}
type Z = {write ["prop"]: string}
)");
LUAU_REQUIRE_ERROR_COUNT(4, result);
CHECK("read keyword is illegal here" == toString(result.errors[0]));
CHECK(Location{{1, 18}, {1, 22}} == result.errors[0].location);
CHECK("write keyword is illegal here" == toString(result.errors[1]));
CHECK(Location{{2, 18}, {2, 23}} == result.errors[1].location);
CHECK("read keyword is illegal here" == toString(result.errors[2]));
CHECK(Location{{4, 18}, {4, 22}} == result.errors[2].location);
CHECK("write keyword is illegal here" == toString(result.errors[3]));
CHECK(Location{{5, 18}, {5, 23}} == result.errors[3].location);
}
TEST_CASE_FIXTURE(Fixture, "read_ond_write_only_indexers_are_unsupported")
{
ScopedFastFlag sff[] = {
{FFlag::LuauReadWritePropertySyntax, true},
{FFlag::DebugLuauDeferredConstraintResolution, false}
};
CheckResult result = check(R"(
type T = {read [string]: number}
type U = {write [string]: boolean}
)");
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK("read keyword is illegal here" == toString(result.errors[0]));
CHECK(Location{{1, 18}, {1, 22}} == result.errors[0].location);
CHECK("write keyword is illegal here" == toString(result.errors[1]));
CHECK(Location{{2, 18}, {2, 23}} == result.errors[1].location);
}
TEST_CASE_FIXTURE(Fixture, "table_writes_introduce_write_properties")
{
ScopedFastFlag sff[] = {
{FFlag::LuauReadWritePropertySyntax, true},
{FFlag::DebugLuauDeferredConstraintResolution, true}
};
CheckResult result = check(R"(
function oc(player, speaker)
local head = speaker.Character:FindFirstChild('Head')
speaker.Character = player[1].Character
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK("<a, b...>({{ read Character: t1 }}, { Character: t1 }) -> () "
"where "
"t1 = { read FindFirstChild: (t1, string) -> (a, b...) }" == toString(requireType("oc")));
}
TEST_SUITE_END();