[BUG] OSError: [Errno 22] Invalid argument and No incoming connection from debugger client

[febb0e]

Describe the bug
When using the Robotcode extension for Robot Framework in VS Code, I encounter the following errors when debugging:

• OSError: [Errno 22] Invalid argument
• TimeoutError: Unable to connect to RobotCode debugger.
• Error: No incoming connection from a debugger client

These errors occur especially when I try to relaunch the debugger from an open session or when stopping the instance and quickly debugging again.

Steps To Reproduce

• Open a Robot Framework project in VS Code.
• Start a debugging session using the Robotcode extension.
• Stop the debugging session.
• Quickly start the debugging session again OR use restart from debugger toolbar.
• Observe the errors.

If possible add some example source code like:

***Settings***
Library  Collections

***Test Cases***
a simple test
    do something    # this should shown something

Expected behavior
I expect the debugger to start without errors, even when quickly restarting the debugging session.

Screenshots/ Videos

Logs
VSCode "Output" view for RobotCode:

Starting debug launcher in stdio mode: example/.venv/bin/python -u /user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/tool/robotcode debug-launch --stdio`

Stack trace for core.py:

Exception has occurred: SystemExit
255
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/robotcode/debugger/run.py", line 197, in run_debugger
    server.protocol.wait_for_client(wait_for_client_timeout)
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/robotcode/debugger/server.py", line 123, in wait_for_client
    raise TimeoutError("Timeout waiting for client")
TimeoutError: Timeout waiting for client

The above exception was the direct cause of the following exception:

  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/robotcode/debugger/cli.py", line 178, in debug
    ctx=ctx,

                app=app,

                args=list(robot_options_and_args),

                mode=mode,

                addresses=bind,

                port=port if port is not None else DEBUGGER_DEFAULT_PORT,

                pipe_name=pipe_name,

                debug=debug,

                stop_on_entry=stop_on_entry,

                wait_for_client=wait_for_client,

                wait_for_client_timeout=wait_for_client_timeout,

                configuration_done_timeout=configuration_done_timeout,

                debugpy=debugpy,

                debugpy_wait_for_client=debugpy_wait_for_client,

                debugpy_port=debugpy_port,

                output_messages=output_messages,

                output_log=output_log,

                output_timestamps=output_timestamps,

                group_output=group_output,

            )

        )
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/robotcode/debugger/run.py", line 199, in run_debugger
    raise ConnectionError("No incomming connection from a debugger client") from e
ConnectionError: No incomming connection from a debugger client

The above exception was the direct cause of the following exception:

  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 1082, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 1697, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 1443, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 788, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/decorators.py", line 92, in new_func
    return ctx.invoke(f, obj, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 788, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/decorators.py", line 33, in new_func
    return f(get_current_context(), *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/robotcode/debugger/cli.py", line 206, in debug
    raise UnknownError(str(e)) from e
robotcode.plugin.UnknownError: No incomming connection from a debugger client

During handling of the above exception, another exception occurred:

  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 1100, in main
    sys.exit(e.exit_code)
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/libs/click/core.py", line 1161, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/user/.vscode/extensions/d-biehl.robotcode-0.108.1/bundled/tool/robotcode/__main__.py", line 27, in <module>
    windows_expand_args=False,

        default_map={"launcher_script": str(pathlib.Path(__file__).parent)},

    )
SystemExit: 255

Additional context
No additional context

Desktop (please complete the following information):

• VS Code Version: 1.97.0
• RobotCode Version: 0.108.1
• OS: Darwin arm64 24.3.0
• Python Version: 3.12.9
• RobotFramework Version: 7.2
• Robocop Version: 5.8.1
• Robotidy Version: 4.16.0

[Dor-bl]

+1

[Dor-bl]

@febb0e Seems like this issue won't reproduce with the latest version. Can u try as well?

[febb0e]

@febb0e Seems like this issue won't reproduce with the latest version. Can u try as well?

@Dor-bl
Unfortunately, when I stop a debugging session and wait for the process to close. When I quickly start a new debugging session or I restart the open debugging session the issue persists on my side.

• VS Code Version: 1.98.0
• RobotCode Version: 1.0.0
• OS: Darwin arm64 24.3.0
• Python Version: 3.13.2
• RobotFramework Version: 7.2.2
• Robocop Version: 5.8.1
• Robotidy Version: 4.16.0

[Dor-bl]

@febb0e You are correct; issue still repro.
I thought this was behind me :(

[simonmeggle]

I can confirm that this issue still exists (RobotCode 1.2.0 on VSC 1.100.0, MacOS 15.3.2)

[d-biehl]

@febb0e @simonmeggle @Dor-bl

If you have time, can you confirm that this is fixed.

Because there is currently no good way to upload a prerelease to the VSCode marketplace, because the marketplace does not fully support semantic versioning, you must download the current dev release from here under the the assets you can found the vsix file for vscode and the robotcode4ij zip file for pycharm.

[simonmeggle]

Great to hear & happy to test - which VSIX file is the correct one? robotcode_plugin?

[d-biehl]

there is only one vsix file robotcode-1.3.0-dev.5.vsix

not the whl files!!!!

[simonmeggle]

Ah, being able to read is an advantage. 😃