`RBMap<StringName, V>` doesn't have unique order or it is meaningless

[TokageItLab]

Godot version

4.1

System information

Any

Issue description

Perhaps because the entity of StringName is a memory address, the order of StringName is not unique when it is used as a key in RBMap.

RBMap<StringName, V> is used in several classes/places:

• project_settings.cpp
• gdscript_byte_codegen.h
• java_class_wrapper.h
• jni_singleton.h

There are two ways to solve this problem, and we should choose one of them depends on each case:

• Make RBMap<StringName, V> work
  • Is it correct way to go implicitly converting StringName to String in RBMap?
  • RBMap<StringName, V, StringName::AlphCompare> can be used
• Replace RBMap<StringName, V> in some classes with HashMap<StringName, V> or RBMap<String, V>

Steps to reproduce

If you run the following code anywhere, you can see that the order changes each time Godot is launched.

RBMap<StringName, int> rbm;
rbm.insert(StringName("a"), 0);
rbm.insert(StringName("b"), 1);
rbm.insert(StringName("c"), 2);
rbm.insert(StringName("d"), 3);
rbm.insert(StringName("e"), 4);
String concat;
for (const KeyValue<StringName, int> &E : rbm) {
    concat += "[" + String(E.key) + ",";
    concat += itos(E.value) + "]";
}
WARN_PRINT(concat);

Minimal reproduction project

RBMap is a C++ class and is not exported to gdscript, so there is no project. Run the above code in any .cpp.

[AThousandShips]

StringName compares by pointer, as you mentioned the appropriate way to do that is to use StringName::AlphCompare, the reason why StringName compares this way is performance, and the order will be stable, though newer names might end up before older ones depending on allocations

[TokageItLab]

Closed by #79595.