Alternate approach to fix list.pop() return type inference - #47
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Tobias-Kohn merged 1 commit intoAug 6, 2026
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pop() was hard-coded to return the list type itself instead of the item type, so e.g. get_actors().pop().remove() resolved .remove() against list.remove(x) instead of the actual item class's remove(), leaking the wrong signature into autocomplete. Also fixed append/extend/insert/remove/ reverse/sort, which had the same hard-coded-to-self bug but should return None. Mirrors the BuiltinMethod/getMethodType pattern used for dict.keys() rather than an AST-walker echo marker: MUTABLE_SEQ registers "pop" as a shared BuiltinMethod template, and TypeAstWalker.getTypeOfAttr binds it to the receiver's own PrimitiveType (e.g. list[Actor] rather than plain list) at each attribute access, since a field shared across every instance of a type can't otherwise see which concrete instance it was accessed on. ListType overrides getMethodType to answer "pop" with its item type.
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This is an alternate approach to pull request #45 to achieve the same aim, based on your dev-tk branch. (Note the PR is targeting to merge into that branch, not into master.)
Reminder of the problem: pop() was hard-coded to return the list type itself instead of the item type, so e.g. get_actors().pop().remove() resolved .remove() against list.remove(x) instead of the actual item class's remove(), leaking the wrong signature into autocomplete. Also append/extend/insert/remove/ reverse/sort would return a list type, rather than None.
This PR mirrors the BuiltinMethod/getMethodType pattern used for dict.keys() rather than an AST-walker echo marker: MUTABLE_SEQ registers "pop" as a shared BuiltinMethod template, and TypeAstWalker.getTypeOfAttr binds it to the receiver's own PrimitiveType (e.g. list[Actor] rather than plain list) at each attribute access, since a field shared across every instance of a type can't otherwise see which concrete instance it was accessed on. ListType overrides getMethodType to answer "pop" with its item type.
See how you find this alternative.