// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details #include "Luau/TypeInfer.h" #include "Luau/Type.h" #include "Fixture.h" #include "doctest.h" using namespace Luau; LUAU_FASTFLAG(DebugLuauDeferredConstraintResolution); TEST_SUITE_BEGIN("IntersectionTypes"); TEST_CASE_FIXTURE(Fixture, "select_correct_union_fn") { CheckResult result = check(R"( type A = (number) -> (string) type B = (string) -> (number) local f:A & B local b = f(10) -- b is a string local c = f("a") -- c is a number )"); LUAU_REQUIRE_NO_ERRORS(result); CHECK_EQ(requireType("b"), builtinTypes->stringType); CHECK_EQ(requireType("c"), builtinTypes->numberType); } TEST_CASE_FIXTURE(Fixture, "table_combines") { CheckResult result = check(R"( type A={a:number} type B={b:string} local c:A & B = {a=10, b="s"} )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "table_combines_missing") { CheckResult result = check(R"( type A={a:number} type B={b:string} local c:A & B = {a=10} )"); REQUIRE(result.errors.size() == 1); } TEST_CASE_FIXTURE(Fixture, "impossible_type") { CheckResult result = check(R"( local c:number&string = 10 )"); REQUIRE(result.errors.size() == 1); } TEST_CASE_FIXTURE(Fixture, "table_extra_ok") { CheckResult result = check(R"( type A={a:number} type B={b:string} local c:A & B local d:A = c )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "fx_intersection_as_argument") { CheckResult result = check(R"( type A = (number) -> (string) type B = (string) -> (number) type C = (A) -> (number) local f:A & B local g:C local b = g(f) )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "fx_union_as_argument_fails") { CheckResult result = check(R"( type A = (number) -> (string) type B = (string) -> (number) type C = (A) -> (number) local f:A | B local g:C local b = g(f) )"); REQUIRE(!result.errors.empty()); } TEST_CASE_FIXTURE(Fixture, "argument_is_intersection") { CheckResult result = check(R"( type A = (number | boolean) -> number local f: A f(5) f(true) )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "should_still_pick_an_overload_whose_arguments_are_unions") { CheckResult result = check(R"( type A = (number | boolean) -> number type B = (string | nil) -> string local f: A & B local a1, a2 = f(1), f(true) local b1, b2 = f("foo"), f(nil) )"); LUAU_REQUIRE_NO_ERRORS(result); CHECK_EQ(*requireType("a1"), *builtinTypes->numberType); CHECK_EQ(*requireType("a2"), *builtinTypes->numberType); CHECK_EQ(*requireType("b1"), *builtinTypes->stringType); CHECK_EQ(*requireType("b2"), *builtinTypes->stringType); } TEST_CASE_FIXTURE(Fixture, "propagates_name") { const std::string code = R"( type A={a:number} type B={b:string} local c:A&B local b = c )"; const std::string expected = R"( type A={a:number} type B={b:string} local c:A&B local b:A&B=c )"; CHECK_EQ(expected, decorateWithTypes(code)); } TEST_CASE_FIXTURE(Fixture, "index_on_an_intersection_type_with_property_guaranteed_to_exist") { CheckResult result = check(R"( type A = {x: {y: number}} type B = {x: {y: number}} local t: A & B local r = t.x )"); LUAU_REQUIRE_NO_ERRORS(result); if (FFlag::DebugLuauDeferredConstraintResolution) CHECK("{| y: number |}" == toString(requireType("r"))); else CHECK("{| y: number |} & {| y: number |}" == toString(requireType("r"))); } TEST_CASE_FIXTURE(Fixture, "index_on_an_intersection_type_works_at_arbitrary_depth") { CheckResult result = check(R"( type A = {x: {y: {z: {thing: string}}}} type B = {x: {y: {z: {thing: string}}}} local t: A & B local r = t.x.y.z.thing )"); LUAU_REQUIRE_NO_ERRORS(result); if (FFlag::DebugLuauDeferredConstraintResolution) { CHECK_EQ("string", toString(requireType("r"))); } else { CHECK_EQ("string & string", toString(requireType("r"))); } } TEST_CASE_FIXTURE(Fixture, "index_on_an_intersection_type_with_mixed_types") { CheckResult result = check(R"( type A = {x: number} type B = {x: string} local t: A & B local r = t.x )"); LUAU_REQUIRE_NO_ERRORS(result); if (FFlag::DebugLuauDeferredConstraintResolution) CHECK_EQ("never", toString(requireType("r"))); else CHECK_EQ("number & string", toString(requireType("r"))); } TEST_CASE_FIXTURE(Fixture, "index_on_an_intersection_type_with_one_part_missing_the_property") { CheckResult result = check(R"( type A = {x: number} type B = {} local t: A & B local r = t.x )"); LUAU_REQUIRE_NO_ERRORS(result); CHECK_EQ("number", toString(requireType("r"))); } TEST_CASE_FIXTURE(Fixture, "index_on_an_intersection_type_with_one_property_of_type_any") { CheckResult result = check(R"( type A = {y: number} type B = {x: any} local t: A & B local r = t.x )"); LUAU_REQUIRE_NO_ERRORS(result); CHECK_EQ(*builtinTypes->anyType, *requireType("r")); } TEST_CASE_FIXTURE(Fixture, "index_on_an_intersection_type_with_all_parts_missing_the_property") { CheckResult result = check(R"( type A = {} type B = {} local function f(t: A & B) local x = t.x end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); UnknownProperty* up = get(result.errors[0]); REQUIRE_MESSAGE(up, result.errors[0].data); CHECK_EQ(up->key, "x"); } TEST_CASE_FIXTURE(Fixture, "table_intersection_write") { CheckResult result = check(R"( type X = { x: number } type XY = X & { y: number } local a : XY = { x = 1, y = 2 } a.x = 10 )"); LUAU_REQUIRE_NO_ERRORS(result); result = check(R"( type X = {} type XY = X & { x: number, y: number } local a : XY = { x = 1, y = 2 } a.x = 10 )"); LUAU_REQUIRE_NO_ERRORS(result); result = check(R"( type X = { x: number } type Y = { y: number } type XY = X & Y local a : XY = { x = 1, y = 2 } a.x = 10 )"); LUAU_REQUIRE_NO_ERRORS(result); result = check(R"( type A = { x: {y: number} } type B = { x: {y: number} } local t : A & B = { x = { y = 1 } } t.x = { y = 4 } t.x.y = 40 )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "table_intersection_write_sealed") { CheckResult result = check(R"( type X = { x: number } type Y = { y: number } type XY = X & Y local a : XY = { x = 1, y = 2 } a.z = 10 )"); LUAU_REQUIRE_ERROR_COUNT(1, result); auto e = toString(result.errors[0]); CHECK_EQ("Cannot add property 'z' to table 'X & Y'", e); } TEST_CASE_FIXTURE(Fixture, "table_intersection_write_sealed_indirect") { CheckResult result = check(R"( type X = { x: (number) -> number } type Y = { y: (string) -> string } type XY = X & Y local xy : XY = { x = function(a: number) return -a end, y = function(a: string) return a .. "b" end } function xy.z(a:number) return a * 10 end function xy:y(a:number) return a * 10 end function xy:w(a:number) return a * 10 end )"); LUAU_REQUIRE_ERROR_COUNT(4, result); CHECK_EQ(toString(result.errors[0]), R"(Type '(string, number) -> string' could not be converted into '(string) -> string' caused by: Argument count mismatch. Function expects 2 arguments, but only 1 is specified)"); CHECK_EQ(toString(result.errors[1]), "Cannot add property 'z' to table 'X & Y'"); CHECK_EQ(toString(result.errors[2]), "Type 'number' could not be converted into 'string'"); CHECK_EQ(toString(result.errors[3]), "Cannot add property 'w' to table 'X & Y'"); } TEST_CASE_FIXTURE(Fixture, "table_write_sealed_indirect") { // After normalization, previous 'table_intersection_write_sealed_indirect' is identical to this one CheckResult result = check(R"( type XY = { x: (number) -> number, y: (string) -> string } local xy : XY = { x = function(a: number) return -a end, y = function(a: string) return a .. "b" end } function xy.z(a:number) return a * 10 end function xy:y(a:number) return a * 10 end function xy:w(a:number) return a * 10 end )"); LUAU_REQUIRE_ERROR_COUNT(4, result); CHECK_EQ(toString(result.errors[0]), R"(Type '(string, number) -> string' could not be converted into '(string) -> string' caused by: Argument count mismatch. Function expects 2 arguments, but only 1 is specified)"); CHECK_EQ(toString(result.errors[1]), "Cannot add property 'z' to table 'XY'"); CHECK_EQ(toString(result.errors[2]), "Type 'number' could not be converted into 'string'"); CHECK_EQ(toString(result.errors[3]), "Cannot add property 'w' to table 'XY'"); } TEST_CASE_FIXTURE(BuiltinsFixture, "table_intersection_setmetatable") { CheckResult result = check(R"( local t: {} & {} setmetatable(t, {}) )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "error_detailed_intersection_part") { CheckResult result = check(R"( type X = { x: number } type Y = { y: number } type Z = { z: number } type XYZ = X & Y & Z local a: XYZ = 3 )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), R"(Type 'number' could not be converted into 'X & Y & Z' caused by: Not all intersection parts are compatible. Type 'number' could not be converted into 'X')"); } TEST_CASE_FIXTURE(Fixture, "error_detailed_intersection_all") { CheckResult result = check(R"( type X = { x: number } type Y = { y: number } type Z = { z: number } type XYZ = X & Y & Z local a: XYZ local b: number = a )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), R"(Type 'X & Y & Z' could not be converted into 'number'; none of the intersection parts are compatible)"); } TEST_CASE_FIXTURE(Fixture, "overload_is_not_a_function") { check(R"( --!nonstrict function _(...):((typeof(not _))&(typeof(not _)))&((typeof(not _))&(typeof(not _))) _(...)(setfenv,_,not _,"")[_] = nil end do end _(...)(...,setfenv,_):_G() )"); } TEST_CASE_FIXTURE(Fixture, "no_stack_overflow_from_flattenintersection") { CheckResult result = check(R"( local l0,l0 repeat type t0 = ((any)|((any)&((any)|((any)&((any)|(any))))))&(t0) function _(l0):(t0)&(t0) while nil do end end until _(_)(_)._ )"); LUAU_REQUIRE_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "intersect_bool_and_false") { CheckResult result = check(R"( local x : (boolean & false) local y : false = x -- OK local z : true = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type 'boolean & false' could not be converted into 'true'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "intersect_false_and_bool_and_false") { CheckResult result = check(R"( local x : false & (boolean & false) local y : false = x -- OK local z : true = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); // TODO: odd stringification of `false & (boolean & false)`.) CHECK_EQ(toString(result.errors[0]), "Type 'boolean & false & false' could not be converted into 'true'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "intersect_saturate_overloaded_functions") { CheckResult result = check(R"( local x : ((number?) -> number?) & ((string?) -> string?) local y : (nil) -> nil = x -- OK local z : (number) -> number = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number?) -> number?) & ((string?) -> string?)' could not be converted into '(number) -> number'; " "none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "union_saturate_overloaded_functions") { CheckResult result = check(R"( local x : ((number) -> number) & ((string) -> string) local y : ((number | string) -> (number | string)) = x -- OK local z : ((number | boolean) -> (number | boolean)) = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number) -> number) & ((string) -> string)' could not be converted into '(boolean | number) -> " "boolean | number'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "intersection_of_tables") { CheckResult result = check(R"( local x : { p : number?, q : string? } & { p : number?, q : number?, r : number? } local y : { p : number?, q : nil, r : number? } = x -- OK local z : { p : nil } = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '{| p: number?, q: number?, r: number? |} & {| p: number?, q: string? |}' could not be converted into " "'{| p: nil |}'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "intersection_of_tables_with_top_properties") { CheckResult result = check(R"( local x : { p : number?, q : any } & { p : unknown, q : string? } local y : { p : number?, q : string? } = x -- OK local z : { p : string?, q : number? } = x -- Not OK )"); if (FFlag::DebugLuauDeferredConstraintResolution) { LUAU_REQUIRE_ERROR_COUNT(2, result); CHECK_EQ(toString(result.errors[0]), "Type '{| p: number?, q: string? |}' could not be converted into '{| p: string?, q: number? |}'\n" "caused by:\n" " Property 'p' is not compatible. Type 'number?' could not be converted into 'string?'\n" "caused by:\n" " Not all union options are compatible. Type 'number' could not be converted into 'string?'\n" "caused by:\n" " None of the union options are compatible. For example: Type 'number' could not be converted into 'string' in an invariant context"); CHECK_EQ(toString(result.errors[1]), "Type '{| p: number?, q: string? |}' could not be converted into '{| p: string?, q: number? |}'\n" "caused by:\n" " Property 'q' is not compatible. Type 'string?' could not be converted into 'number?'\n" "caused by:\n" " Not all union options are compatible. Type 'string' could not be converted into 'number?'\n" "caused by:\n" " None of the union options are compatible. For example: Type 'string' could not be converted into 'number' in an invariant context"); } else { LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '{| p: number?, q: any |} & {| p: unknown, q: string? |}' could not be converted into '{| p: string?, " "q: number? |}'; none of the intersection parts are compatible"); } } TEST_CASE_FIXTURE(Fixture, "intersection_of_tables_with_never_properties") { CheckResult result = check(R"( local x : { p : number?, q : never } & { p : never, q : string? } -- OK local y : { p : never, q : never } = x -- OK local z : never = x -- OK )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "overloaded_functions_returning_intersections") { CheckResult result = check(R"( local x : ((number?) -> ({ p : number } & { q : number })) & ((string?) -> ({ p : number } & { r : number })) local y : (nil) -> { p : number, q : number, r : number} = x -- OK local z : (number?) -> { p : number, q : number, r : number} = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number?) -> {| p: number |} & {| q: number |}) & ((string?) -> {| p: number |} & {| r: number |})' could not be converted into " "'(number?) -> {| p: number, q: number, r: number |}'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloaded_functions_mentioning_generic") { CheckResult result = check(R"( function f() local x : ((number?) -> (a | number)) & ((string?) -> (a | string)) local y : (nil) -> a = x -- OK local z : (number?) -> a = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number?) -> a | number) & ((string?) -> a | string)' could not be converted into '(number?) -> a'; " "none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloaded_functions_mentioning_generics") { CheckResult result = check(R"( function f() local x : ((a?) -> (a | b)) & ((c?) -> (b | c)) local y : (nil) -> ((a & c) | b) = x -- OK local z : (a?) -> ((a & c) | b) = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((a?) -> a | b) & ((c?) -> b | c)' could not be converted into '(a?) -> (a & c) | b'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloaded_functions_mentioning_generic_packs") { CheckResult result = check(R"( function f() local x : ((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...)) local y : ((nil, a...) -> (nil, b...)) = x -- OK local z : ((nil, b...) -> (nil, a...)) = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))' could not be converted " "into '(nil, b...) -> (nil, a...)'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_unknown_result") { CheckResult result = check(R"( function f() local x : ((number) -> number) & ((nil) -> unknown) local y : (number?) -> unknown = x -- OK local z : (number?) -> number? = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((nil) -> unknown) & ((number) -> number)' could not be converted into '(number?) -> number?'; none " "of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_unknown_arguments") { CheckResult result = check(R"( function f() local x : ((number) -> number?) & ((unknown) -> string?) local y : (number) -> nil = x -- OK local z : (number?) -> nil = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number) -> number?) & ((unknown) -> string?)' could not be converted into '(number?) -> nil'; none " "of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_never_result") { CheckResult result = check(R"( function f() local x : ((number) -> number) & ((nil) -> never) local y : (number?) -> number = x -- OK local z : (number?) -> never = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((nil) -> never) & ((number) -> number)' could not be converted into '(number?) -> never'; none of " "the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_never_arguments") { CheckResult result = check(R"( function f() local x : ((number) -> number?) & ((never) -> string?) local y : (never) -> nil = x -- OK local z : (number?) -> nil = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((never) -> string?) & ((number) -> number?)' could not be converted into '(number?) -> nil'; none " "of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_overlapping_results_and_variadics") { CheckResult result = check(R"( local x : ((string?) -> (string | number)) & ((number?) -> ...number) local y : ((nil) -> (number, number?)) = x -- OK local z : ((string | number) -> (number, number?)) = x -- Not OK )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((number?) -> (...number)) & ((string?) -> number | string)' could not be converted into '(number | " "string) -> (number, number?)'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_weird_typepacks_1") { CheckResult result = check(R"( function f() local x : (() -> a...) & (() -> b...) local y : (() -> b...) & (() -> a...) = x -- OK local z : () -> () = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '(() -> (a...)) & (() -> (b...))' could not be converted into '() -> ()'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_weird_typepacks_2") { CheckResult result = check(R"( function f() local x : ((a...) -> ()) & ((b...) -> ()) local y : ((b...) -> ()) & ((a...) -> ()) = x -- OK local z : () -> () = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((a...) -> ()) & ((b...) -> ())' could not be converted into '() -> ()'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_weird_typepacks_3") { CheckResult result = check(R"( function f() local x : (() -> a...) & (() -> (number?,a...)) local y : (() -> (number?,a...)) & (() -> a...) = x -- OK local z : () -> (number) = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '(() -> (a...)) & (() -> (number?, a...))' could not be converted into '() -> number'; none of the intersection parts are compatible"); } TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_weird_typepacks_4") { CheckResult result = check(R"( function f() local x : ((a...) -> ()) & ((number,a...) -> number) local y : ((number,a...) -> number) & ((a...) -> ()) = x -- OK local z : (number?) -> () = x -- Not OK end )"); LUAU_REQUIRE_ERROR_COUNT(1, result); CHECK_EQ(toString(result.errors[0]), "Type '((a...) -> ()) & ((number, a...) -> number)' could not be converted into '(number?) -> ()'; none of " "the intersection parts are compatible"); } TEST_CASE_FIXTURE(BuiltinsFixture, "intersect_metatables") { CheckResult result = check(R"( local a : string? = nil local b : number? = nil local x = setmetatable({}, { p = 5, q = a }); local y = setmetatable({}, { q = b, r = "hi" }); local z = setmetatable({}, { p = 5, q = nil, r = "hi" }); type X = typeof(x) type Y = typeof(y) type Z = typeof(z) local xy : X&Y = z; local yx : Y&X = z; z = xy; z = yx; )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(BuiltinsFixture, "intersect_metatable_subtypes") { CheckResult result = check(R"( local x = setmetatable({ a = 5 }, { p = 5 }); local y = setmetatable({ b = "hi" }, { p = 5, q = "hi" }); local z = setmetatable({ a = 5, b = "hi" }, { p = 5, q = "hi" }); type X = typeof(x) type Y = typeof(y) type Z = typeof(z) local xy : X&Y = z; local yx : Y&X = z; z = xy; z = yx; )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(BuiltinsFixture, "intersect_metatables_with_properties") { CheckResult result = check(R"( local x = setmetatable({ a = 5 }, { p = 5 }); local y = setmetatable({ b = "hi" }, { q = "hi" }); local z = setmetatable({ a = 5, b = "hi" }, { p = 5, q = "hi" }); type X = typeof(x) type Y = typeof(y) type Z = typeof(z) local xy : X&Y = z; z = xy; )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(BuiltinsFixture, "intersect_metatable_with_table") { CheckResult result = check(R"( local x = setmetatable({ a = 5 }, { p = 5 }); local z = setmetatable({ a = 5, b = "hi" }, { p = 5 }); type X = typeof(x) type Y = { b : string } type Z = typeof(z) -- TODO: once we have shape types, we should be able to initialize these with z local xy : X&Y; local yx : Y&X; z = xy; z = yx; )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "CLI-44817") { CheckResult result = check(R"( type X = {x: number} type Y = {y: number} type Z = {z: number} type XY = {x: number, y: number} type XYZ = {x:number, y: number, z: number} local xy: XY = {x = 0, y = 0} local xyz: XYZ = {x = 0, y = 0, z = 0} local xNy: X&Y = xy local xNyNz: X&Y&Z = xyz local t1: XY = xNy -- Type 'X & Y' could not be converted into 'XY' local t2: XY = xNyNz -- Type 'X & Y & Z' could not be converted into 'XY' local t3: XYZ = xNyNz -- Type 'X & Y & Z' could not be converted into 'XYZ' )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(Fixture, "less_greedy_unification_with_intersection_types") { if (!FFlag::DebugLuauDeferredConstraintResolution) return; CheckResult result = check(R"( local function f(t): { x: number } & { x: string } local x = t.x return t end )"); LUAU_REQUIRE_NO_ERRORS(result); // TODO? We do not simplify types from explicit annotations. CHECK_EQ("({| x: number |} & {| x: string |}) -> {| x: number |} & {| x: string |}", toString(requireType("f"))); } TEST_CASE_FIXTURE(Fixture, "less_greedy_unification_with_intersection_types_2") { if (!FFlag::DebugLuauDeferredConstraintResolution) return; CheckResult result = check(R"( local function f(t: { x: number } & { x: string }) return t.x end )"); LUAU_REQUIRE_NO_ERRORS(result); CHECK_EQ("({| x: number |} & {| x: string |}) -> never", toString(requireType("f"))); } TEST_CASE_FIXTURE(BuiltinsFixture, "index_property_table_intersection_1") { CheckResult result = check(R"( type Foo = { Bar: string, } & { Baz: number } local x: Foo = { Bar = "1", Baz = 2 } local y = x.Bar )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_CASE_FIXTURE(BuiltinsFixture, "index_property_table_intersection_2") { ScopedFastFlag sff{"LuauIndexTableIntersectionStringExpr", true}; CheckResult result = check(R"( type Foo = { Bar: string, } & { Baz: number } local x: Foo = { Bar = "1", Baz = 2 } local y = x["Bar"] )"); LUAU_REQUIRE_NO_ERRORS(result); } TEST_SUITE_END();