Fix get_method from named lambda

[sepTN]

Fix #80434

Snippet used:

extends Node2D

func _ready():
	var fun = func test(): pass
	print(fun.get_method())

Before PR:

After PR:

[dalexeev]

1. I'm not sure if this method should return for an unnamed lambda: <anonymous lambda> or an empty string. <anonymous lambda> is more descriptive, but perhaps it should be documented.
2. GDScript: The same should be done for GDScriptRPCCallable.
3. Core: CallableCustomBind, CallableCustomUnbind and CallableCustomMethodPointerBase already implement the method.
4. C#: ManagedCallable and BaseSignalCallable did not implement the method.

func test():
    pass

@rpc
func test_rpc():
    pass

func _ready() -> void:
    var l1 := func (): pass
    var l2 := func lambda(): pass

    print(test.get_method()) # test
    print(test_rpc.get_method()) # Error: Can't get method on CallableCustom "Node(node.gd)::test_rpc (rpc)".
    print(l1.get_method()) # <anonymous lambda>
    print(l2.get_method()) # lambda

[sepTN]

I do think it should stay that way, <anonymous lambda> is more descriptive than an empty string.

Just updated the branch with a commit for the GDScriptRPCCallable, so is this the desired behavior?

---

Snippet:

extends Node2D

func test():
		pass

@rpc
func test_rpc():
		pass

func _ready() -> void:
		var l1 := func (): pass
		var l2 := func lambda(): pass

		print(test.get_method())
		print(test_rpc.get_method())
		print(l1.get_method())
		print(l2.get_method())

Without this PR (current master branch):

With this PR:

---

Also, I have no prior Godot C# experience so I have no idea how to implement that in ManagedCallable and BaseSignalCallable, wouldn't it be better to have it on its own PR?

[dalexeev]

You should squash the commits into one, according to the docs.

I'm not sure if this method should return for an unnamed lambda: <anonymous lambda> or an empty string. <anonymous lambda> is more descriptive, but perhaps it should be documented.

godot/doc/classes/Callable.xml

Lines 138 to 143 in 4714e95

	<method name="get_method" qualifiers="const">
	<return type="StringName" />
	<description>
	Returns the name of the method represented by this [Callable]. If the callable is a lambda function, returns the function's name.
	</description>
	</method>

Returns the name of the method represented by this [Callable]. If the callable is a GDScript lambda function, returns the function's name or [code]"<anonymous lambda>"[/code].

C#: ManagedCallable and BaseSignalCallable did not implement the method.

I'm not sure about that, just noticed. let the C# team decide.

[dalexeev]

Looks good to me.

[akien-mga]

Looks correct.

[akien-mga]

Thanks!

[YuriSizov]

Cherry-picked for 4.1.3.