Nested Graphs Issues

[herronelou]

I know from #376 that you said that the Group Nodes and Subgraphs aren't quite fully developed, but I thought I'd add a large-ish example along with some issues I'm facing.

I've reported a few in #450 #451 #452, but let me add a few things here.

Full example is available in: https://gist.github.com/herronelou/e60a4dacc24e27810c4ac04b6ee90962
Note: This does not require RV to run, all the data I would obtain from RV has been naked into a dict and the RV commands are being mocked.

Issue 1 - Collapsing Groups destroys connections

Notice that in https://gist.github.com/herronelou/e60a4dacc24e27810c4ac04b6ee90962#file-rv_node_graph-py-L633 I had to not collapse the groups after building them. This is because collapsing a group and re-expanding it does not seem to preserve connections:

For example, look at the defaultLayout group:
Before collapsing:

After collapsing and re-expanding:

I suspect this could be because I attempt to add inputs to my nodes dynamically, which may be messing with the serialization, but I haven't seen instructions saying this isn't supported.

Edit: Confirmed that this serializes OK if I add the input directly in my node definition.

Issue 2 - Corruption of the navigation bar.

When there are nested groups, they open fairly nicely on top, however after a certain level of nesting it seems I encounter some kind of bug:

As you can see on the animated GIF above, when I click on the bar for deeply nested graphs, the graph widget itself fails to display.
Here is the accompanying traceback:

Traceback (most recent call last):
  File "\NodeGraphQt\0.6.38\python\NodeGraphQt\base\graph.py", line 2752, in _on_navigation_changed
    child_node = self.sub_graphs[rm_node_id].node
KeyError: '0x1ba40873b20'

[herronelou]

Regarding issue 2, it turns out they are not deeply nested groups, but multiple subgroups of the main group that happened to all be expanded at once and it does not like that.