luau/tests/TypeInfer.intersectionTypes.test.cpp
aaron b23d43496b
Sync to upstream/release/641 (#1382)
### What's new

* Light update this week, mostly fast flag cleanups.

### New Solver

* Rename flag to enable new solver from
`DebugLuauDeferredConstraintResolution` to `LuauSolverV2`
* Added support for magic functions for the new type checker (as opposed
to the type inference component)
* Improved handling of `string.format` with magic function improvements
* Cleaning up some of the reported errors by the new type checker
* Minor refactoring of `TypeChecker2.cpp` that happens to make the diff
very hard to read.

---

### Internal Contributors

Co-authored-by: Aaron Weiss <aaronweiss@roblox.com>
Co-authored-by: Andy Friesen <afriesen@roblox.com>
Co-authored-by: Vighnesh Vijay <vvijay@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>
Co-authored-by: Junseo Yoo <jyoo@roblox.com>
2024-08-30 13:16:51 -07:00

1343 lines
43 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 "ScopedFlags.h"
#include "doctest.h"
using namespace Luau;
LUAU_FASTFLAG(LuauSolverV2);
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 function foo(f: A & B)
return f(10), f("a")
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(((number) -> string) & ((string) -> number)) -> (string, number)", toString(requireType("foo")));
}
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 function f(t: A & B): A
return t
end
)");
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 function foo(f: A & B, g: C)
return g(f)
end
)");
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 function foo(f: A | B, g: C)
return g(f)
end
)");
REQUIRE(!result.errors.empty());
}
TEST_CASE_FIXTURE(Fixture, "argument_is_intersection")
{
CheckResult result = check(R"(
type A = (number | boolean) -> number
local function foo(f: A)
f(5)
f(true)
end
)");
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) -> string
type B = (string) -> number
local function foo(f: A & B)
return f(1), f("five")
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(((number) -> string) & ((string) -> number)) -> (string, number)", toString(requireType("foo")));
}
TEST_CASE_FIXTURE(Fixture, "propagates_name")
{
const std::string code = R"(
type A={a:number}
type B={b:string}
local function f(t: A & B)
return t
end
)";
const std::string expected = R"(
type A={a:number}
type B={b:string}
local function f(t: A & B): A&B
return t
end
)";
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 function f(t: A & B)
return t.x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK("(A & B) -> { y: number }" == toString(requireType("f")));
else
CHECK("(A & B) -> {| y: number |} & {| y: number |}" == toString(requireType("f")));
}
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 function f(t: A & B)
return t.x.y.z.thing
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("(A & B) -> string", toString(requireType("f")));
else
CHECK_EQ("(A & B) -> string & string", toString(requireType("f")));
}
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 function f(t: A & B)
return t.x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
if (FFlag::LuauSolverV2)
CHECK_EQ("(A & B) -> never", toString(requireType("f")));
else
CHECK_EQ("(A & B) -> number & string", toString(requireType("f")));
}
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 function f(t: A & B)
return t.x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(A & B) -> number", toString(requireType("f")));
}
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 function f(t: A & B)
return t.x
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
CHECK_EQ("(A & B) -> any", toString(requireType("f")));
}
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 }
function f(t: XY)
t.x = 10
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
result = check(R"(
type X = {}
type XY = X & { x: number, y: number }
function f(t: XY)
t.x = 10
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
result = check(R"(
type X = { x: number }
type Y = { y: number }
type XY = X & Y
function f(t: XY)
t.x = 10
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
result = check(R"(
type A = { x: {y: number} }
type B = { x: {y: number} }
function f(t: A & B)
t.x = { y = 4 }
t.x.y = 40
end
)");
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
function f(t: XY)
t.z = 10
end
)");
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")
{
ScopedFastFlag dcr{
FFlag::LuauSolverV2, false
}; // CLI-116476 Subtyping between type alias and an equivalent but not named type isn't working.
CheckResult result = check(R"(
type X = { x: (number) -> number }
type Y = { y: (string) -> string }
type XY = X & Y
function f(t: XY)
function t.z(a:number) return a * 10 end
function t:y(a:number) return a * 10 end
function t:w(a:number) return a * 10 end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(toString(result.errors[0]), "Cannot add property 'z' to table 'X & Y'");
CHECK_EQ(toString(result.errors[1]), "Cannot add property 'w' to table 'X & Y'");
}
else
{
LUAU_REQUIRE_ERROR_COUNT(4, result);
const std::string expected = 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(expected, toString(result.errors[0]));
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")
{
ScopedFastFlag dcr{FFlag::LuauSolverV2, false}; // CLI-
// 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);
const std::string expected = 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(expected, toString(result.errors[0]));
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"(
function f(t: {} & {})
setmetatable(t, {})
end
)");
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);
const std::string expected = 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')";
const std::string dcrExprected =
R"(Type 'number' could not be converted into 'X & Y & Z'; type number (number) is not a subtype of X & Y & Z[0] (X)
type number (number) is not a subtype of X & Y & Z[1] (Y)
type number (number) is not a subtype of X & Y & Z[2] (Z))";
if (FFlag::LuauSolverV2)
CHECK_EQ(dcrExprected, toString(result.errors[0]));
else
CHECK_EQ(expected, toString(result.errors[0]));
}
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
function f(a: XYZ): number
return a
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ(
R"(Type pack 'X & Y & Z' could not be converted into 'number'; type X & Y & Z[0][0] (X) is not a subtype of number[0] (number)
type X & Y & Z[0][1] (Y) is not a subtype of number[0] (number)
type X & Y & Z[0][2] (Z) is not a subtype of number[0] (number))",
toString(result.errors[0])
);
}
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"(
function f(x: boolean & false)
local y : false = x -- OK
local z : true = x -- Not OK
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ(
R"(Type 'boolean & false' could not be converted into 'true'; type boolean & false[0] (boolean) is not a subtype of true (true)
type boolean & false[1] (false) is not a subtype of true (true))",
toString(result.errors[0])
);
}
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"(
function f(x: false & (boolean & false))
local y : false = x -- OK
local z : true = x -- Not OK
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
// TODO: odd stringification of `false & (boolean & false)`.)
if (FFlag::LuauSolverV2)
CHECK_EQ(
R"(Type 'boolean & false & false' could not be converted into 'true'; type boolean & false & false[0] (false) is not a subtype of true (true)
type boolean & false & false[1] (boolean) is not a subtype of true (true)
type boolean & false & false[2] (false) is not a subtype of true (true))",
toString(result.errors[0])
);
else
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"(
function foo(x: ((number?) -> number?) & ((string?) -> string?))
local y : (nil) -> nil = x -- Not OK (fixed in DCR)
local z : (number) -> number = x -- Not OK
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
const std::string expected1 = R"(Type
'((number?) -> number?) & ((string?) -> string?)'
could not be converted into
'(nil) -> nil'; type ((number?) -> number?) & ((string?) -> string?)[0].returns()[0][0] (number) is not a subtype of (nil) -> nil.returns()[0] (nil)
type ((number?) -> number?) & ((string?) -> string?)[1].returns()[0][0] (string) is not a subtype of (nil) -> nil.returns()[0] (nil))";
const std::string expected2 = R"(Type
'((number?) -> number?) & ((string?) -> string?)'
could not be converted into
'(number) -> number'; type ((number?) -> number?) & ((string?) -> string?)[0].returns()[0][1] (nil) is not a subtype of (number) -> number.returns()[0] (number)
type ((number?) -> number?) & ((string?) -> string?)[1].arguments()[0] (string?) is not a supertype of (number) -> number.arguments()[0] (number)
type ((number?) -> number?) & ((string?) -> string?)[1].returns()[0][0] (string) is not a subtype of (number) -> number.returns()[0] (number)
type ((number?) -> number?) & ((string?) -> string?)[1].returns()[0][1] (nil) is not a subtype of (number) -> number.returns()[0] (number))";
CHECK_EQ(expected1, toString(result.errors[0]));
CHECK_EQ(expected2, toString(result.errors[1]));
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((number?) -> number?) & ((string?) -> string?)'
could not be converted into
'(number) -> number'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "union_saturate_overloaded_functions")
{
ScopedFastFlag dcr{
FFlag::LuauSolverV2, false
}; // CLI-116474 Semantic subtyping of assignments needs to decide how to interpret intersections of functions
CheckResult result = check(R"(
function f(x: ((number) -> number) & ((string) -> string))
local y : ((number | string) -> (number | string)) = x -- OK
local z : ((number | boolean) -> (number | boolean)) = x -- Not OK
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((number) -> number) & ((string) -> string)'
could not be converted into
'(boolean | number) -> boolean | number'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "intersection_of_tables")
{
CheckResult result = check(R"(
function f(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
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected =
(FFlag::LuauSolverV2)
? R"(Type '{ p: number?, q: number?, r: number? } & { p: number?, q: string? }' could not be converted into '{ p: nil }'; type { p: number?, q: number?, r: number? } & { p: number?, q: string? }[0][read "p"][0] (number) is not exactly { p: nil }[read "p"] (nil)
type { p: number?, q: number?, r: number? } & { p: number?, q: string? }[1][read "p"][0] (number) is not exactly { p: nil }[read "p"] (nil))"
:
R"(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)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "intersection_of_tables_with_top_properties")
{
CheckResult result = check(R"(
function f(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
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(
R"(Type
'{ p: number?, q: any } & { p: unknown, q: string? }'
could not be converted into
'{ p: string?, q: number? }'; type { p: number?, q: any } & { p: unknown, q: string? }[0][read "p"] (number?) is not exactly { p: string?, q: number? }[read "p"][0] (string)
type { p: number?, q: any } & { p: unknown, q: string? }[0][read "p"][0] (number) is not exactly { p: string?, q: number? }[read "p"] (string?)
type { p: number?, q: any } & { p: unknown, q: string? }[0][read "q"] (any) is not exactly { p: string?, q: number? }[read "q"] (number?)
type { p: number?, q: any } & { p: unknown, q: string? }[1][read "p"] (unknown) is not exactly { p: string?, q: number? }[read "p"] (string?)
type { p: number?, q: any } & { p: unknown, q: string? }[1][read "q"] (string?) is not exactly { p: string?, q: number? }[read "q"][0] (number)
type { p: number?, q: any } & { p: unknown, q: string? }[1][read "q"][0] (string) is not exactly { p: string?, q: number? }[read "q"] (number?))",
toString(result.errors[0])
);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(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)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "intersection_of_tables_with_never_properties")
{
CheckResult result = check(R"(
function f(x : { p : number?, q : never } & { p : never, q : string? })
local y : { p : never, q : never } = x -- OK
local z : never = x -- OK
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "overloaded_functions_returning_intersections")
{
CheckResult result = check(R"(
function f(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
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(
R"(Type
'((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })'
could not be converted into
'(nil) -> { p: number, q: number, r: number }'; type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[0].returns()[0][0] ({ p: number }) is not a subtype of (nil) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number })
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[0].returns()[0][1] ({ q: number }) is not a subtype of (nil) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number })
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[1].returns()[0][0] ({ p: number }) is not a subtype of (nil) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number })
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[1].returns()[0][1] ({ r: number }) is not a subtype of (nil) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number }))",
toString(result.errors[0])
);
CHECK_EQ(
R"(Type
'((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })'
could not be converted into
'(number?) -> { p: number, q: number, r: number }'; type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[0].returns()[0][0] ({ p: number }) is not a subtype of (number?) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number })
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[0].returns()[0][1] ({ q: number }) is not a subtype of (number?) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number })
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[1].arguments()[0] (string?) is not a supertype of (number?) -> { p: number, q: number, r: number }.arguments()[0][0] (number)
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[1].returns()[0][0] ({ p: number }) is not a subtype of (number?) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number })
type ((number?) -> { p: number } & { q: number }) & ((string?) -> { p: number } & { r: number })[1].returns()[0][1] ({ r: number }) is not a subtype of (number?) -> { p: number, q: number, r: number }.returns()[0] ({ p: number, q: number, r: number }))",
toString(result.errors[1])
);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
CHECK_EQ(
R"(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)",
toString(result.errors[0])
);
}
}
TEST_CASE_FIXTURE(Fixture, "overloaded_functions_mentioning_generic")
{
CheckResult result = check(R"(
function f<a>()
function g(x : ((number?) -> (a | number)) & ((string?) -> (a | string)))
local y : (nil) -> a = x -- OK
local z : (number?) -> a = x -- Not OK
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(0, result);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((number?) -> a | number) & ((string?) -> a | string)'
could not be converted into
'(number?) -> a'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "overloaded_functions_mentioning_generics")
{
CheckResult result = check(R"(
function f<a,b,c>()
function g(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
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((a?) -> a | b) & ((c?) -> b | c)'
could not be converted into
'(a?) -> (a & c) | b'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "overloaded_functions_mentioning_generic_packs")
{
CheckResult result = check(R"(
function f<a...,b...>()
function g(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
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(
R"(Type
'((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))'
could not be converted into
'(nil, a...) -> (nil, b...)'; type ((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))[0].returns()[0][0] (number) is not a subtype of (nil, a...) -> (nil, b...).returns()[0] (nil)
type ((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))[1].returns()[0][0] (string) is not a subtype of (nil, a...) -> (nil, b...).returns()[0] (nil))",
toString(result.errors[0])
);
CHECK_EQ(
R"(Type
'((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))'
could not be converted into
'(nil, b...) -> (nil, a...)'; type ((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))[0].returns()[0][0] (number) is not a subtype of (nil, b...) -> (nil, a...).returns()[0] (nil)
type ((number?, a...) -> (number?, b...)) & ((string?, a...) -> (string?, b...))[1].returns()[0][0] (string) is not a subtype of (nil, b...) -> (nil, a...).returns()[0] (nil))",
toString(result.errors[1])
);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(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)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_unknown_result")
{
ScopedFastFlag dcr{
FFlag::LuauSolverV2, false
}; // CLI-116474 Semantic subtyping of assignments needs to decide how to interpret intersections of functions
CheckResult result = check(R"(
function f<a...,b...>()
function g(x : ((number) -> number) & ((nil) -> unknown))
local y : (number?) -> unknown = x -- OK
local z : (number?) -> number? = x -- Not OK
end
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((nil) -> unknown) & ((number) -> number)'
could not be converted into
'(number?) -> number?'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_unknown_arguments")
{
ScopedFastFlag dcr{
FFlag::LuauSolverV2, false
}; // CLI-116474 Semantic subtyping of assignments needs to decide how to interpret intersections of functions
CheckResult result = check(R"(
function f<a...,b...>()
function g(x : ((number) -> number?) & ((unknown) -> string?))
local y : (number) -> nil = x -- OK
local z : (number?) -> nil = x -- Not OK
end
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((number) -> number?) & ((unknown) -> string?)'
could not be converted into
'(number?) -> nil'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_never_result")
{
CheckResult result = check(R"(
function f<a...,b...>()
function g(x : ((number) -> number) & ((nil) -> never))
local y : (number?) -> number = x -- OK
local z : (number?) -> never = x -- Not OK
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
CHECK_EQ(
R"(Type
'((nil) -> never) & ((number) -> number)'
could not be converted into
'(number?) -> number'; type ((nil) -> never) & ((number) -> number)[0].arguments()[0] (number) is not a supertype of (number?) -> number.arguments()[0][1] (nil)
type ((nil) -> never) & ((number) -> number)[1].arguments()[0] (nil) is not a supertype of (number?) -> number.arguments()[0][0] (number))",
toString(result.errors[0])
);
CHECK_EQ(
R"(Type
'((nil) -> never) & ((number) -> number)'
could not be converted into
'(number?) -> never'; type ((nil) -> never) & ((number) -> number)[0].arguments()[0] (number) is not a supertype of (number?) -> never.arguments()[0][1] (nil)
type ((nil) -> never) & ((number) -> number)[0].returns()[0] (number) is not a subtype of (number?) -> never.returns()[0] (never)
type ((nil) -> never) & ((number) -> number)[1].arguments()[0] (nil) is not a supertype of (number?) -> never.arguments()[0][0] (number))",
toString(result.errors[1])
);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((nil) -> never) & ((number) -> number)'
could not be converted into
'(number?) -> never'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_never_arguments")
{
CheckResult result = check(R"(
function f<a...,b...>()
function g(x : ((number) -> number?) & ((never) -> string?))
local y : (never) -> nil = x -- OK
local z : (number?) -> nil = x -- Not OK
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_ERROR_COUNT(2, result);
const std::string expected1 = R"(Type
'((never) -> string?) & ((number) -> number?)'
could not be converted into
'(never) -> nil'; type ((never) -> string?) & ((number) -> number?)[0].returns()[0][0] (number) is not a subtype of (never) -> nil.returns()[0] (nil)
type ((never) -> string?) & ((number) -> number?)[1].returns()[0][0] (string) is not a subtype of (never) -> nil.returns()[0] (nil))";
const std::string expected2 = R"(Type
'((never) -> string?) & ((number) -> number?)'
could not be converted into
'(number?) -> nil'; type ((never) -> string?) & ((number) -> number?)[0].arguments()[0] (number) is not a supertype of (number?) -> nil.arguments()[0][1] (nil)
type ((never) -> string?) & ((number) -> number?)[0].returns()[0][0] (number) is not a subtype of (number?) -> nil.returns()[0] (nil)
type ((never) -> string?) & ((number) -> number?)[1].arguments()[0] (never) is not a supertype of (number?) -> nil.arguments()[0][0] (number)
type ((never) -> string?) & ((number) -> number?)[1].arguments()[0] (never) is not a supertype of (number?) -> nil.arguments()[0][1] (nil)
type ((never) -> string?) & ((number) -> number?)[1].returns()[0][0] (string) is not a subtype of (number?) -> nil.returns()[0] (nil))";
CHECK_EQ(expected1, toString(result.errors[0]));
CHECK_EQ(expected2, toString(result.errors[1]));
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((never) -> string?) & ((number) -> number?)'
could not be converted into
'(number?) -> nil'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_overlapping_results_and_variadics")
{
ScopedFastFlag dcr{
FFlag::LuauSolverV2, false
}; // CLI-116474 Semantic subtyping of assignments needs to decide how to interpret intersections of functions
CheckResult result = check(R"(
function f(x : ((string?) -> (string | number)) & ((number?) -> ...number))
local y : ((nil) -> (number, number?)) = x -- OK
local z : ((string | number) -> (number, number?)) = x -- Not OK
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'((number?) -> (...number)) & ((string?) -> number | string)'
could not be converted into
'(number | string) -> (number, number?)'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_weird_typepacks_1")
{
CheckResult result = check(R"(
function f<a...,b...>()
function g(x : (() -> a...) & (() -> b...))
local y : (() -> b...) & (() -> a...) = x -- OK
local z : () -> () = x -- Not OK
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
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...>()
function g(x : ((a...) -> ()) & ((b...) -> ()))
local y : ((b...) -> ()) & ((a...) -> ()) = x -- OK
local z : () -> () = x -- Not OK
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
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...>()
function g(x : (() -> a...) & (() -> (number?,a...)))
local y : (() -> (number?,a...)) & (() -> a...) = x -- OK
local z : () -> (number) = x -- Not OK
end
end
)");
if (FFlag::LuauSolverV2)
{
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
LUAU_REQUIRE_ERROR_COUNT(1, result);
const std::string expected = R"(Type
'(() -> (a...)) & (() -> (number?, a...))'
could not be converted into
'() -> number'; none of the intersection parts are compatible)";
CHECK_EQ(expected, toString(result.errors[0]));
}
}
TEST_CASE_FIXTURE(Fixture, "overloadeded_functions_with_weird_typepacks_4")
{
CheckResult result = check(R"(
function f<a...>()
function g(x : ((a...) -> ()) & ((number,a...) -> number))
local y : ((number,a...) -> number) & ((a...) -> ()) = x -- OK
local z : (number?) -> () = x -- Not OK
end
end
)");
LUAU_REQUIRE_ERROR_COUNT(1, result);
if (FFlag::LuauSolverV2)
{
CHECK_EQ(
R"(Type
'((a...) -> ()) & ((number, a...) -> number)'
could not be converted into
'((a...) -> ()) & ((number, a...) -> number)'; at [0].returns(), is not a subtype of number
type ((a...) -> ()) & ((number, a...) -> number)[1].arguments().tail() (a...) is not a supertype of ((a...) -> ()) & ((number, a...) -> number)[0].arguments().tail() (a...))",
toString(result.errors[0])
);
}
else
{
CHECK_EQ(
R"(Type
'((a...) -> ()) & ((number, a...) -> number)'
could not be converted into
'(number?) -> ()'; none of the intersection parts are compatible)",
toString(result.errors[0])
);
}
}
TEST_CASE_FIXTURE(BuiltinsFixture, "intersect_metatables")
{
// CLI-117121 - Intersection of types are not compatible with the equivalent alias
if (FFlag::LuauSolverV2)
return;
if (FFlag::LuauSolverV2)
{
CheckResult result = check(R"(
function f(a: string?, b: string?)
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)
function g(xy: X&Y, yx: Y&X): (Z, Z)
return xy, yx
end
g(z, z)
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
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)
function f(xy: X&Y, yx: Y&X): (Z, Z)
return xy, yx
end
f(z, z)
)");
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)
function f(xy: X&Y): Z
return xy
end
f(z)
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "intersect_metatable_with_table")
{
if (FFlag::LuauSolverV2)
{
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)
function f(xy: X&Y, yx: Y&X): (Z, Z)
return xy, yx
end
f(z, z)
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
else
{
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}
function f(xy: XY, xyz: XYZ): (X&Y, X&Y&Z)
return xy, xyz
end
local xNy, xNyNz = f({x = 0, y = 0}, {x = 0, y = 0, z = 0})
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::LuauSolverV2)
return;
CheckResult result = check(R"(
local function f(t): { x: number } & { x: string }
local x = t.x
return t
end
)");
LUAU_REQUIRE_ERROR_COUNT(3, result);
CHECK_EQ("(never) -> { x: number } & { x: string }", toString(requireType("f")));
}
TEST_CASE_FIXTURE(Fixture, "less_greedy_unification_with_intersection_types_2")
{
if (!FFlag::LuauSolverV2)
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 }
function f(x: Foo)
return x.Bar
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(BuiltinsFixture, "index_property_table_intersection_2")
{
CheckResult result = check(R"(
type Foo = {
Bar: string,
} & { Baz: number }
function f(x: Foo)
return x["Bar"]
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cli_80596_simplify_degenerate_intersections")
{
ScopedFastFlag dcr{FFlag::LuauSolverV2, true};
CheckResult result = check(R"(
type A = {
x: number?,
}
type B = {
x: number?,
}
type C = A & B
function f(obj: C): number
return obj.x or 3
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_CASE_FIXTURE(Fixture, "cli_80596_simplify_more_realistic_intersections")
{
ScopedFastFlag dcr{FFlag::LuauSolverV2, true};
CheckResult result = check(R"(
type A = {
x: number?,
y: string?,
}
type B = {
x: number?,
z: string?,
}
type C = A & B
function f(obj: C): number
return obj.x or 3
end
)");
LUAU_REQUIRE_NO_ERRORS(result);
}
TEST_SUITE_END();