GDScript being broken in many places after #72487

[maiself]

Godot version

394bb0e

System information

arch linux

Issue description

#72487 broke my project in quite a few ways. I haven't yet had time to look into everything. Including here one example with assigning enum values.

SCRIPT ERROR: Parse Error: Invalid operands "Input::MouseMode" and "Input::MouseMode" for "==" operator.
SCRIPT ERROR: Parse Error: Cannot assign a new value to a constant.

Here is the full log output: https://pastebin.com/raw/TbdyfMSX

Steps to reproduce

Add the following code to a new project:

Input.mouse_mode = Input.MOUSE_MODE_VISIBLE

Minimal reproduction project

None yet

[maiself]

#72500 contains same bug.

[Chaosus]

cc @vnen

[HungryProton]

This PR also breaks anything using get_node or $, whether @onready is used or not.

@onready var my_node = $Button

Displays this error message despite using @onready

Parse Error: The default value is using "$" which won't return nodes in the scene tree before "_ready()" is called. Use the "@onready" annotation to solve this. (Warning treated as error.)

[vnen]

Thanks for finding this so quickly. I didn't have the time to test very thoroughly before sending the PR. I'll try to add these to the test cases when submitting a new version.