Play Scene passes an extra cmdline arg.

[zaevi]

Godot version:
3.2.4.beta

OS/device including version:
Win10

Issue description:
When using Play Scene in Editor, it will pass an extra arg (the scene's path) in OS.get_cmdline_args().
I don't know if it's feature or bug.

Steps to reproduce:
Create a scene with script:

func _ready():
    for arg in OS.get_cmdline_args():
        print(arg)

Run scene using Play and Play Scene

Minimal reproduction project:
arg-test.zip

[akien-mga]

That's a feature, passing arguments is how the engine knows whether to run the editor, the project manager, the project (main scene) or a specific scene.

$ godot --help
Godot Engine v3.2.3.stable.mageia - https://godotengine.org
Free and open source software under the terms of the MIT license.
(c) 2007-2020 Juan Linietsky, Ariel Manzur.
(c) 2014-2020 Godot Engine contributors.

Usage: godot [options] [path to scene or 'project.godot' file]

[zaevi]

I mean, the editor shouldn't expose this argument to project.

Running: C:/Dev/Godot/dev/godot.windows.opt.tools.64.mono.exe --path C:/Users/zaevi/source/Godot/arg-test --remote-debug 127.0.0.1:6007 --allow_focus_steal_pid 31500 --position 448,240 res://Main.tscn

The previous arguments are "hidden" (which I could not get them by OS.get_cmdline_args() in my project), except for the scene path.
This argument is handled by engine, not my project, so I think it should hide as same.