luau/tests/TypeInfer.intersectionTypes.test.cpp
vegorov-rbx 62483d40f0
Sync to upstream/release/562 (#828)
* Fixed rare use-after-free in analysis during table unification

A lot of work these past months went into two new Luau components:
* A near full rewrite of the typechecker using a new deferred constraint
resolution system
* Native code generation for AoT/JiT compilation of VM bytecode into x64
(avx)/arm64 instructions

Both of these components are far from finished and we don't provide
documentation on building and using them at this point.
However, curious community members expressed interest in learning about
changes that go into these components each week, so we are now listing
them here in the 'sync' pull request descriptions.

---
New typechecker can be enabled by setting
DebugLuauDeferredConstraintResolution flag to 'true'.
It is considered unstable right now, so try it at your own risk.
Even though it already provides better type inference than the current
one in some cases, our main goal right now is to reach feature parity
with current typechecker.
Features which improve over the capabilities of the current typechecker
are marked as '(NEW)'.

Changes to new typechecker:
* Regular for loop index and parameters are now typechecked
* Invalid type annotations on local variables are ignored to improve
autocomplete
* Fixed missing autocomplete type suggestions for function arguments
* Type reduction is now performed to produce simpler types to be
presented to the user (error messages, custom LSPs)
* Internally, complex types like '((number | string) & ~(false?)) |
string' can be produced, which is just 'string | number' when simplified
* Fixed spots where support for unknown and never types was missing
* (NEW) Length operator '#' is now valid to use on top table type, this
type comes up when doing typeof(x) == "table" guards and isn't available
in current typechecker

---
Changes to native code generation:
* Additional math library fast calls are now lowered to x64: math.ldexp,
math.round, math.frexp, math.modf, math.sign and math.clamp
2023-02-03 11:26:13 -08:00

941 lines
29 KiB
C++

// 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;
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"), typeChecker.stringType);
CHECK_EQ(requireType("c"), typeChecker.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"), *typeChecker.numberType);
CHECK_EQ(*requireType("a2"), *typeChecker.numberType);
CHECK_EQ(*requireType("b1"), *typeChecker.stringType);
CHECK_EQ(*requireType("b2"), *typeChecker.stringType);
}
TEST_CASE_FIXTURE(Fixture, "propagates_name")
{
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CheckResult result = check(R"(
type A={a:number}
type B={b:string}
local c:A&B
local b = c
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK("{| a: number, b: string |}" == toString(requireType("b")));
}
else
{
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(*typeChecker.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<UnknownProperty>(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);
CHECK_EQ(toString(result.errors[0]), "Cannot add property 'z' to table 'X & Y'");
}
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);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ(toString(result.errors[0]), R"(Type 'number' could not be converted into '{| x: number, y: number, z: number |}')");
else
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);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ(toString(result.errors[0]), R"(Type '{| x: number, y: number, z: number |}' could not be converted into 'number')");
else
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);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ(toString(result.errors[0]), "Type 'false' could not be converted into 'true'");
else
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);
if (FFlag::DebugLuauDeferredConstraintResolution)
CHECK_EQ(toString(result.errors[0]), "Type 'false' could not be converted into 'true'");
else
{
// 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);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
CHECK_EQ(toString(result.errors[0]),
"Type '{| p: number?, q: nil, r: number? |}' could not be converted into '{| p: nil |}'\n"
"caused by:\n"
" Property 'p' is not compatible. Type 'number?' could not be converted into 'nil'\n"
"caused by:\n"
" Not all union options are compatible. Type 'number' could not be converted into 'nil' in an invariant context");
}
else
{
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")
{
ScopedFastFlag sffs[]{
{"LuauUninhabitedSubAnything2", true},
};
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);
if (FFlag::DebugLuauDeferredConstraintResolution)
{
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");
}
else
{
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<a>()
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<a,b,c>()
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<a...,b...>()
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<a...,b...>()
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<a...,b...>()
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<a...,b...>()
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<a...,b...>()
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<a...,b...>()
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<a...,b...>()
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<a...>()
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<a...>()
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);
CHECK_EQ("(never) -> never", 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("(never) -> never", toString(requireType("f")));
}
TEST_SUITE_END();