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Async flag lost when alias with type parameters (@alias Name<T> async fun) is used

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Avaliação

Dificuldade
3/5
Tempo estimado
1-2 dias
Facilidade para iniciantes
68/100
Tipo de issue
Bug
Clareza
Claramente especificada
Status de atividade
Ativa
Stack de tecnologia
lua
Domínio
compilers

Direção de pesquisa

Reproduce with the issue's ---@alias Name<T> async fun(): T snippets and hover output. The async flag is likely dropped where generic alias types get substituted — start in script/vm/ (alias/global resolution) and script/compiler/ where function types are marked async, then check script/core/diagnostics/await-in-sync.lua for how the flag is read. Done means generic-parameterized async aliases report async on hover and trigger await-in-sync, verified via the repo's test harness under script/tests.

Escrita pelo modelo de indexação a partir do texto da issue.

Descrição

How are you using the lua-language-server?

NeoVim

Which OS are you using?

Linux

What is the issue affecting?

Type Checking

Expected Behaviour

When using alias generics where the alias is an async function, it should be marked with async when I give it a generic type.

```---@alias MyAsyncFunc<T> async fun(): T

---@type MyAsyncFunc<string>
local function my_function()
	return "test"
end

my_function() -- on hover, it shows async

---@diagnostic enable: await-in-sync

local function async_context()
	my_function() -- raises `await-in-sync` warning since the outer function is not marked as async
end
Actual Behaviour

When using alias generics like this, the async flag marked on those functions gets removed:

---@alias Name<T> async fun(): T
---@alias Name2<T> async fun(a: T)
---@alias Name3<T> async fun(a: T): T

Refer to the test cases below:

---@alias AsyncFuncT async fun(): any

---@alias AsyncGenericFuncT<T> async fun(): T

---@alias AnotherAsyncGenericFuncT<T> async fun(val: T)

---@alias DifferentAsyncFormat async fun<T>(val: T): T

---@class TestClass
---@field field AsyncFuncT
---@field generic_field AsyncGenericFuncT<string>
---@field another_generic AnotherAsyncGenericFuncT<integer>
---@field different DifferentAsyncFormat

---@type TestClass
local test_fields = {
	field = function() end, --- correctly marks async
	generic_field = function() -- the function is not tagged as async
		return "hello" -- the return type is correctly tagged as string
	end,
	another_generic = function(num) -- the function is not tagged as async
		print(num) -- the num is correctly tagged as integer
	end,
	different = function(x) -- correctly tags as async
		return x
	end,
}

---@type AsyncFuncT
local function test() end

test() -- correctly tags as async

---@type AsyncGenericFuncT<string>
local function test2()
	return "hello" -- correctly tags the return type as string
end

test2() -- does not tag as async

---@type AnotherAsyncGenericFuncT<integer>
local function test3(num)
	print(num) -- correctly tags as integer
end

test3(2) -- does not tag as async

---@type DifferentAsyncFormat
local function test4(x)
	return x
end

test4(20) -- correctly tags as async

local function non_async()
	test() -- if await-in-sync is enabled, this warns as expected
	-- since the function is not tagged async

	test2() -- gives no warning since its not tagged as async function
	test3(2) -- gives no warns since its not tagged as async function

	test4(4) -- warns as expected when await-in-sync is enabled
end

---@async
local function async_code()
	test() -- no warning as expected when await-in-sync is enabled
	test2()
	test3(2)
	test4(4) -- no warning as expected when await-in-sync is enabled
end

Normal alias with async fun():
Image

Alias with generic with async fun():
Image

Reproduction steps

Tested version: 3.19.1

Create an alias that has a generic beside the name, then hover the function or use it in a context where await-in-sync warning will appear.

Example:

---@alias MyAsyncFunc<T> async fun(): T
---@alias MyAsyncFuncNormal async fun(): any

---@type MyAsyncFunc<string>
local function my_function()
	return "test"
end

---@type MyAsyncFuncNormal
local function working()
	return "test"
end

---@diagnostic enable: await-in-sync

local function async_context()
	my_function() -- should raise `await-in-sync` warning
	working() -- warns with `await-in-sync`
end
Additional Notes

No response

Log File

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Estrelas
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Forks
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Merge médio
8d 9h
PRs com merge (30d)
1

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