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function types don't fully work

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
53/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
rust
Domain
developer-experience

Research direction

The report shows two failures in EmmyLua function type annotations: return checking is skipped for an annotated function value, and parameter hovers show any for the documented fun(x: number, y: number): number example. Start by locating the analyzer code and tests for function type annotations and hover information. Done means both examples enforce the declared return type and show number for x and y.

Written by the indexing model from the issue text.

Description

I'm using emmylua_ls 0.23.1, when I do

---@return string
local function foo()
    return 12
end

I get the warning that I don't return a string. When instead I do

---@type fun():string
local bar = function()
    return 12
end

Then there is no warning at all.

In fact, when using one of the examples from https://github.com/EmmyLuaLs/emmylua-analyzer-rust/blob/main/docs/emmylua_doc/annotations_EN/type.md#examples

-- Function types
---@type fun(x: number, y: number): number
local addFunction = function(x, y)
    return x + y
end

A hover on x and y reveals any, and not number.

Dominant language
Rust
Stars
523
Forks
104
Avg merge
2d 6h
Merged PRs (30d)
23

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