feat: treat array index as nil-able #371
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Expressions like this: ```lua ---@type integer[] local arr = {1, 2, 3} return arr[2] ``` should be considered as type `integer|nil`, since array accesses can always *potentially* return `nil`. This commit marks those expressions as such.
| return Ok(TypeOps::Union.apply(base, &LuaType::Nil)); | ||
| } else if member_key.is_expr() { | ||
| let expr = member_key.get_expr().ok_or(InferFailReason::None)?; | ||
| let expr_type = infer_expr(db, cache, expr.clone())?; | ||
| if check_type_compact(db, &LuaType::Number, &expr_type).is_ok() { | ||
| return Ok(base.clone()); | ||
| return Ok(TypeOps::Union.apply(base, &LuaType::Nil)); |
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I am assuming this is also necessary?
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cc @lewis6991, will this be too annoying in practice? |
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I think we need a configuration for strictly indexing arrays, because I noticed that even in Rust, array access operations do not return Option, and other languages, including TypeScript, do not return T | null. |
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I've gated this change behind a config option, defaulting to |
Expressions like this:
should be considered as type
integer|nil, since array accesses can always potentially returnnil. This commit marks those expressions as such.Related to #248