luau/tests/TopoSort.test.cpp
Andy Friesen c51743268b
Sync to upstream/release/671 (#1787)
# General

* Internally rename `ClassType` to `ExternType`. In definition files,
the syntax to define these types has changed to `declare extern type Foo
with prop: type end`
* Add `luarequire_registermodule` to Luau.Require
* Support yieldable Luau C functions calling other functions
* Store return types as `AstTypePack*` on Ast nodes

## New Solver

* Improve the logic that determines constraint dispatch ordering
* Fix a crash in the type solver that arose when using multi-return
functions with `string.format`
* Fix https://github.com/luau-lang/luau/issues/1736
* Initial steps toward rethinking function generalization:
* Instead of generalizing every type in a function all at once, we will
instead generalize individual type variables once their bounds have been
fully resolved. This will make it possible to properly interleave type
function reduction and generalization.
* Magic functions are no longer considered magical in cases where they
are not explicitly called by the code.
* The most prominent example of this is in `for..in` loops where the
function call is part of the desugaring process.
* Almost all magic functions work by directly inspecting the AST, so
they can't work without an AST fragment anyway.
* Further, none of the magic functions we have are usefully used in this
way.

Co-authored-by: Andy Friesen <afriesen@roblox.com>
Co-authored-by: Ariel Weiss <aaronweiss@roblox.com>
Co-authored-by: Hunter Goldstein <hgoldstein@roblox.com>
Co-authored-by: Sora Kanosue <skanosue@roblox.com>
Co-authored-by: Talha Pathan <tpathan@roblox.com>
Co-authored-by: Varun Saini <vsaini@roblox.com>
Co-authored-by: Vighnesh Vijay <vvijay@roblox.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>
2025-04-25 14:19:27 -07:00

441 lines
10 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#include "Luau/TopoSortStatements.h"
#include "Luau/Transpiler.h"
#include "Fixture.h"
#include "doctest.h"
using namespace Luau;
static std::vector<AstStat*> toposort(AstStatBlock& block)
{
std::vector<AstStat*> result{block.body.begin(), block.body.end()};
Luau::toposort(result);
return result;
}
TEST_SUITE_BEGIN("TopoSortTests");
TEST_CASE_FIXTURE(Fixture, "sorts")
{
AstStatBlock* program = parse(R"(
function A()
return B("high five!")
end
function B(x)
return x
end
)");
auto sorted = toposort(*program);
REQUIRE_EQ(2, sorted.size());
AstStatBlock* block = program->as<AstStatBlock>();
REQUIRE(block != nullptr);
REQUIRE_EQ(2, block->body.size);
// B is sorted ahead of A
CHECK_EQ(block->body.data[1], sorted[0]);
CHECK_EQ(block->body.data[0], sorted[1]);
}
TEST_CASE_FIXTURE(Fixture, "cyclic_dependency_terminates")
{
AstStatBlock* program = parse(R"(
function A()
return B()
end
function B()
return A()
end
)");
auto sorted = toposort(*program);
REQUIRE_EQ(2, sorted.size());
}
TEST_CASE_FIXTURE(Fixture, "doesnt_omit_statements_that_dont_need_sorting")
{
AstStatBlock* program = parse(R"(
local X = {}
function A()
return B(5), B("Hi")
end
local Y = {}
function B(x)
return x
end
local Z = B()
)");
auto sorted = toposort(*program);
REQUIRE_EQ(5, sorted.size());
AstStatBlock* block = program->as<AstStatBlock>();
REQUIRE(block != nullptr);
REQUIRE_EQ(5, block->body.size);
AstStat* X = block->body.data[0];
AstStat* A = block->body.data[1];
AstStat* Y = block->body.data[2];
AstStat* B = block->body.data[3];
AstStat* Z = block->body.data[4];
CHECK_EQ(sorted[0], X);
CHECK_EQ(sorted[1], Y);
CHECK_EQ(sorted[2], B);
CHECK_EQ(sorted[3], Z);
CHECK_EQ(sorted[4], A);
}
TEST_CASE_FIXTURE(Fixture, "slightly_more_complex")
{
AstStatBlock* program = parse(R"(
local T = {}
function T:foo()
return T:bar(999), T:bar("hi")
end
function T:bar(i)
return i
end
)");
auto sorted = toposort(*program);
REQUIRE_EQ(3, sorted.size());
CHECK_EQ(sorted[0], program->body.data[0]);
CHECK_EQ(sorted[1], program->body.data[2]);
CHECK_EQ(sorted[2], program->body.data[1]);
}
TEST_CASE_FIXTURE(Fixture, "reorder_functions_after_dependent_assigns")
{
AstStatBlock* program = parse(R"(
local T = {} -- 0
function T.a() -- 1 depends on (2)
T.b()
end
function T.b() -- 2 depends on (4)
T.c()
end
function make_function() -- 3
return function() end
end
T.c = make_function() -- 4 depends on (3)
T.a() -- 5 depends on (1)
)");
auto sorted = toposort(*program);
REQUIRE_EQ(6, sorted.size());
CHECK_EQ(sorted[0], program->body.data[0]);
CHECK_EQ(sorted[1], program->body.data[3]);
CHECK_EQ(sorted[2], program->body.data[4]);
CHECK_EQ(sorted[3], program->body.data[2]);
CHECK_EQ(sorted[4], program->body.data[1]);
CHECK_EQ(sorted[5], program->body.data[5]);
}
TEST_CASE_FIXTURE(Fixture, "dont_reorder_assigns")
{
AstStatBlock* program = parse(R"(
local T = {} -- 0
function T.a() -- 1 depends on (2)
T.b()
end
function T.b() -- 2 depends on (5)
T.c()
end
function make_function() -- 3
return function() end
end
T.a() -- 4 depends on (1 -> 2 -> 5), but we cannot reorder it after 5!
T.c = make_function() -- 5 depends on (3)
)");
auto sorted = toposort(*program);
REQUIRE_EQ(6, sorted.size());
CHECK_EQ(sorted[0], program->body.data[0]);
CHECK_EQ(sorted[1], program->body.data[3]);
CHECK_EQ(sorted[2], program->body.data[2]);
CHECK_EQ(sorted[3], program->body.data[1]);
CHECK_EQ(sorted[4], program->body.data[4]);
CHECK_EQ(sorted[5], program->body.data[5]);
}
TEST_CASE_FIXTURE(Fixture, "dont_reorder_function_after_assignment_to_global")
{
AstStatBlock* program = parse(R"(
local f
function g()
f()
end
f = function() end
)");
auto sorted = toposort(*program);
REQUIRE_EQ(3, sorted.size());
CHECK_EQ(sorted[0], program->body.data[0]);
CHECK_EQ(sorted[1], program->body.data[1]);
CHECK_EQ(sorted[2], program->body.data[2]);
}
TEST_CASE_FIXTURE(Fixture, "local_functions_need_sorting_too")
{
AstStatBlock* program = parse(R"(
local a = nil -- 0
local function f() -- 1 depends on 4
a.c = 4
end
local function g() -- 2 depends on 1
f()
end
a = {} -- 3
a.c = nil -- 4
)");
auto sorted = toposort(*program);
REQUIRE_EQ(5, sorted.size());
CHECK_EQ(sorted[0], program->body.data[0]);
CHECK_EQ(sorted[1], program->body.data[3]);
CHECK_EQ(sorted[2], program->body.data[4]);
CHECK_EQ(sorted[3], program->body.data[1]);
CHECK_EQ(sorted[4], program->body.data[2]);
}
TEST_CASE_FIXTURE(Fixture, "dont_force_checking_until_an_AstExprCall_needs_the_symbol")
{
AstStatBlock* program = parse(R"(
function A(obj)
C(obj)
end
local B = A -- It would be an error to force checking of A at this point just because the definition of B is an imperative
function C(player)
end
local D = A(nil) -- The real dependency on A is here, where A is invoked.
)");
auto sorted = toposort(*program);
REQUIRE_EQ(4, sorted.size());
auto A = program->body.data[0];
auto B = program->body.data[1];
auto C = program->body.data[2];
auto D = program->body.data[3];
CHECK_EQ(sorted[0], C);
CHECK_EQ(sorted[1], A);
CHECK_EQ(sorted[2], B);
CHECK_EQ(sorted[3], D);
}
TEST_CASE_FIXTURE(Fixture, "dont_reorder_imperatives")
{
AstStatBlock* program = parse(R"(
local temp = work
work = arr
arr = temp
width = width * 2
)");
auto sorted = toposort(*program);
REQUIRE_EQ(4, sorted.size());
}
TEST_CASE_FIXTURE(Fixture, "sort_typealias_first")
{
AstStatBlock* program = parse(R"(
local foo: A = 1
type A = number
)");
auto sorted = toposort(*program);
REQUIRE_EQ(2, sorted.size());
auto A = program->body.data[0];
auto B = program->body.data[1];
CHECK_EQ(sorted[0], B);
CHECK_EQ(sorted[1], A);
}
TEST_CASE_FIXTURE(Fixture, "typealias_of_typeof_is_not_sorted")
{
AstStatBlock* program = parse(R"(
type Foo = typeof(foo)
local function foo(x: number) end
)");
auto sorted = toposort(*program);
REQUIRE_EQ(2, sorted.size());
auto A = program->body.data[0];
auto B = program->body.data[1];
CHECK_EQ(sorted[0], A);
CHECK_EQ(sorted[1], B);
}
TEST_CASE_FIXTURE(Fixture, "nested_type_annotations_depends_on_later_typealiases")
{
AstStatBlock* program = parse(R"(
type Foo = A | B
type B = number
type A = string
)");
auto sorted = toposort(*program);
REQUIRE_EQ(3, sorted.size());
auto Foo = program->body.data[0];
auto B = program->body.data[1];
auto A = program->body.data[2];
CHECK_EQ(sorted[0], B);
CHECK_EQ(sorted[1], A);
CHECK_EQ(sorted[2], Foo);
}
TEST_CASE_FIXTURE(Fixture, "function_return_type_depends_on_type_aliases")
{
AstStatBlock* program = parse(R"(
type callbackFn<K, V> = (element: V, key: K, map: Map<K, V>) -> ()
export type Map<K, V> = {
forEach: (callback: callbackFn<K, V>) -> (),
}
function foo<K, V>(key: K, value: V): Map<K, V>
end
)");
auto sorted = toposort(*program);
REQUIRE_EQ(3, sorted.size());
auto callbackFn = program->body.data[0];
auto Map = program->body.data[1];
auto foo = program->body.data[2];
CHECK_EQ(sorted[0], callbackFn);
CHECK_EQ(sorted[1], Map);
CHECK_EQ(sorted[2], foo);
}
TEST_CASE_FIXTURE(Fixture, "return_comes_last")
{
AstStatBlock* program = parse(R"(
local module = {}
local function confuseCompiler() return module.foo() end
module.foo = function() return "" end
function module.bar(x:number)
confuseCompiler()
return true
end
return module
)");
auto sorted = toposort(*program);
CHECK_EQ(sorted[0], program->body.data[0]);
CHECK_EQ(sorted[2], program->body.data[1]);
CHECK_EQ(sorted[1], program->body.data[2]);
CHECK_EQ(sorted[3], program->body.data[3]);
CHECK_EQ(sorted[4], program->body.data[4]);
}
TEST_CASE_FIXTURE(Fixture, "break_comes_last")
{
AstStatBlock* program = parse(R"(
repeat
local module = {}
local function confuseCompiler() return module.foo() end
module.foo = function() return "" end
break
until true
)");
REQUIRE(program->body.size == 1);
auto repeat = program->body.data[0]->as<AstStatRepeat>();
REQUIRE(repeat);
REQUIRE(repeat->body->body.size == 4);
auto sorted = toposort(*repeat->body);
REQUIRE(sorted.size() == 4);
CHECK_EQ(sorted[3], repeat->body->body.data[3]);
}
TEST_CASE_FIXTURE(Fixture, "continue_comes_last")
{
AstStatBlock* program = parse(R"(
repeat
local module = {}
local function confuseCompiler() return module.foo() end
module.foo = function() return "" end
continue
until true
)");
REQUIRE(program->body.size == 1);
auto repeat = program->body.data[0]->as<AstStatRepeat>();
REQUIRE(repeat);
REQUIRE(repeat->body->body.size == 4);
auto sorted = toposort(*repeat->body);
REQUIRE(sorted.size() == 4);
CHECK_EQ(sorted[3], repeat->body->body.data[3]);
}
TEST_SUITE_END();