Godot 4 State Machine using GDScript
This code is associated with this tutorial: Godot State Machine
The updated version works by only having the current state node as a child of the Statemachine node. It allows for a very simple code structure.
The other states are in a floating state with no parent, so they don't receive calls to the game loop functions such as _process and _input.
The state nodes are identified by their name and must implement an enter() and exit(next_node_name) function.