`---@cast` annotation doesn't respect scope rules

How are you using the lua-language-server?

Visual Studio Code Extension (sumneko.lua)

Which OS are you using?

Windows

What is the issue affecting?

Type Checking

Expected Behaviour

The ---@cast annotation should respect Lua scoping rules.

Actual Behaviour

Let's consider:

--- @class foo
--- @field a number

--- @class bar
--- @field b string

--- @type { [integer]: foo|bar }
local array = {}

for i, instance in ipairs(array) do
	if instance.a then
                -- First if block
		--- @cast instance foo
	end

	if instance.b then
                -- Second if block
	end
end

In the first if block, we cast the instance to the foo type. When hovering over the instance variable in the second if block we can see its type is foo. It would be expected for its type to be bar since the ---@cast happened in different scope.

Reproduction steps

1. Copy-paste the given example code into your text editor.
2. Hover over the instance variable in the second if block.
3. See the error in the popup.

Additional Notes

No response

Log File

No response

首先，在 Visual Studio Code 扩展中使用提供的 Lua 示例重现该问题，并检查类型检查如何处理两个 if 块的作用域。完成标准是，向 foo 的 cast 仅在第一个块内生效，而第二个块中的实例保留适当的推断类型，而不是 foo。