bug: Multiple union types are not well supported

[jecisc]

Did you check existing issues?

• I have read all the tree-sitter docs if it relates to using the parser
• I have searched the existing issues of tree-sitter-python

Tree-Sitter CLI Version, if relevant (output of tree-sitter --version)

Compiled from main

Describe the bug

I am trying to parse some code with union types with more than 2 possible types and TreeSitter python does not seems to manage this right.

Steps To Reproduce/Bad Parse Tree

Here is the minimal example I can produce:

def f( arg: IO[bytes] | int | float ): pass

Here is what I get:

We see a union_type node with two types. I was expecting 3.

This is even worst with this piece of code:

def f( arg: IO[bytes] | int | List[int] ): pass

We end up with a subscript for List[int] instead of a generic type

Expected Behavior/Parse Tree

Instead of the binary_operator node containing identifiers I was expecting the union_type to contain 2..n children. Currently union_type seems to be possible only with 2 children.

Repro

I used Pharo-Tree-Sitter integration to produce the tree from this piece of code:



def f( arg: IO[bytes] | int | List[int] ): pass