GUI FGs: returning WORK_DONE doesn't shut down the FG

[willcode]

What happened?

Returning -1 from work() in a Python Embedded Block does not terminate the flowgraph. Possibly something wrong with the PyBind11 inheritance tree?

The enums here

gnuradio/gnuradio-runtime/python/gnuradio/gr/bindings/block_python.cc

Line 493 in 04d4f0d

py::enum_<gr::block::work_return_t>(m, "work_return_t")

(based on)

gnuradio/gnuradio-runtime/include/gnuradio/block.h

Line 66 in 04d4f0d

enum work_return_t { WORK_CALLED_PRODUCE = -2, WORK_DONE = -1 };

Can not be returned here

gnuradio/gnuradio-runtime/python/gnuradio/gr/bindings/block_gateway.h

Line 96 in 04d4f0d

int general_work(int noutput_items,

Error:

thread_body_wrapper :error: ERROR thread[thread-per-block[0]: <block EPB: File Source to Tagged Stream(3)>]: TypeError: '>' not supported between instances of 'gnuradio.gr.gr_python.work_return_t' and 'int'

At:
  /dcs/lib/python3.10/site-packages/gnuradio/gr/gateway.py(303): consume_items
  /dcs/lib/python3.10/site-packages/gnuradio/gr/gateway.py(200): handle_general_work

System Information

Any

GNU Radio Version

3.11-git (main)

Specific Version

No response

Steps to Reproduce the Problem

Return gr.WORK_DONE from a Python block.

Relevant log output

No response

[willcode]

@mormj Any clue why returning -1 from an EPB does not terminate the flowgraph, or print the "we're done" message in block_executor.cc? Is this a PyBind11 inheritance problem? I can't see how it all fits together.

@ryanvolz It looks like you might be familiar with this area too.

It turns out that GUI flowgraphs don't shut down (the graphics at least) on DONE. This has nothing to do with Python. Returning -1 from a EPB does shut down a non-GUI flowgraph as expected.

[marcusmueller]

Can reproduce:

import numpy as np
from gnuradio import gr

class blk(gr.sync_block):  # other base classes are basic_block, decim_block, interp_block
    def __init__(self):  # only default arguments here
        gr.sync_block.__init__(
            self,
            name='instant return -1 block',   # will show up in GRC
            in_sig=[np.complex64],
            out_sig=[]
        )

    def work(self, input_items, output_items):
        return -1

happily keeps that window open.
https://gist.github.com/marcusmueller/901bf36bbb0e52929a8db9a0b23d7e62