Orphan symbol ?

It seems that some symbols are orphans. Example : a block inside block, which is inside another block, ... The block exists (in current example, between lines 11 & 15), but this symbol doesn't have parent node. This is a problem for dev tools like Gvls, because without parents, we can't go upstream inside symbol tree, and so, and therefore no symbols as result

Toto.vala

static void titi (int nombre, SourceFunc delegue) {
	string var_a = "toto";
	double var_b = 33.3363;
	
	
}

static void toto() {
	var nombre = 25.36536;
	
	titi (33, () => {
		var chaine = "toto";
		
		return false;
	});
}

static void main() {}

main.vala

public static void main (string[] args) {
	var context = new Vala.CodeContext();
	context.set_target_profile (Vala.Profile.GOBJECT);
	context.add_external_package ("gio-2.0");
	var path = Vala.CodeContext.realpath ("Toto.vala");
	context.add_source_filename (path);
	
	var parser = new Vala.Parser();
	Vala.CodeContext.push (context);
	parser.parse (context);
	
	foreach (var sf in context.get_source_files()) {
		print ("%s\n", sf.filename);
		if (sf.filename == path) {
			var locator = new BlockLocator();
			var block = locator.locate (sf, 13, 1);
			if (block != null) {
				print ("parent node : %s\n", (block.parent_node == null).to_string());
				print ("parent symbol : %s\n", (block.parent_symbol == null).to_string());
				
				/*
					parent node : true
					parent symbol : true
				*/
			}
		}
	}
}

For the test, I use locator from Anjuta project https://gitlab.gnome.org/GNOME/anjuta/-/blob/master/plugins/language-support-vala/locator.vala