LuaLS / LuaLS/lua-language-server
Inference failure when conditionally swapping variable?
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Description
Is the following expected? Why does inference fail at all?
local a, b = 5, 8
if a < b then
b, a = a, b
-- ^ Unknown: cannot infer type.
end
print("(" .. a .. ", " .. b .. ")")
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First steps
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Research direction
Start by reproducing the conditional multiple-assignment example from the issue and inspect the inference path for b, a = a, b. Trace why the reassignment produces an unknown-type diagnostic, then verify that the snippet no longer reports the diagnostic while preserving the inferred types of a and b.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- lua
- Domain
- devtools
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 55/100