I'm trying to make a JavaScript subclass of GtkTreeStore, overriding the row_draggable() method on the GtkTreeDragSource interface. This crashes gjs. My hypothesis is that this is because GtkTreeStore already implements GtkTreeDragSource, but I haven't looked into it yet. gjs version 1.36.1-2 from Debian.

Output

 % gjs subclass-GtkTreeStore-override-row_draggable.js

** (gjs:14866): CRITICAL **: g_object_info_get_class_struct: assertion `GI_IS_OBJECT_INFO (info)' failed
zsh: segmentation fault  gjs subclass-GtkTreeStore-override-row_draggable.js

subclass-GtkTreeStore-no-override.js

const Lang = imports.lang;
const Gtk = imports.gi.Gtk;

const Model = new Lang.Class({
    Name: 'Model',
    Extends: Gtk.TreeStore,
    Implements: [ Gtk.TreeDragSource ]
});

subclass-GtkTreeStore-override-row_draggable.js

const Lang = imports.lang;
const Gtk = imports.gi.Gtk;

const Model = new Lang.Class({
    Name: 'Model',
    Extends: Gtk.TreeStore,
    Implements: [ Gtk.TreeDragSource ],

    vfunc_row_draggable: function() {
        return true;
    }
});