Several test-driven fixes

- Improved test suite exposed several issues with the handling of
command line arguments which are now fixed
- Fixed a race condition that would cause remote characters to be
  lost intermittently when running remote commands that finish
  immediately.
- Added automated testing that actually spins up a random listener
  and initiator in a private Reticulum network and passes data
  between them, uncovering more issues which are now fixed.
- Fixed (hopefully) an issue where `rnsh` doesn't know what
  version it is.

tests/helpers.py

@@ -0,0 +1,131 @@
+import logging
+import types
+import typing
+import tempfile
+
+import pytest
+
+import rnsh.rnsh
+import asyncio
+import rnsh.process
+import contextlib
+import threading
+import os
+import pathlib
+import tests
+import shutil
+import random
+
+module_logger = logging.getLogger(__name__)
+
+module_abs_filename = os.path.abspath(tests.__file__)
+module_dir = os.path.dirname(module_abs_filename)
+
+
+class SubprocessReader(contextlib.AbstractContextManager):
+    def __init__(self, argv: [str], env: dict = None, name: str = None):
+        self._log = module_logger.getChild(self.__class__.__name__ + ("" if name is None else f"({name})"))
+        self.name = name or "subproc"
+        self.process: rnsh.process.CallbackSubprocess
+        self.loop = asyncio.get_running_loop()
+        self.env = env or os.environ.copy()
+        self.argv = argv
+        self._lock = threading.RLock()
+        self._stdout = bytearray()
+        self.return_code: int = None
+        self.process = rnsh.process.CallbackSubprocess(argv=self.argv,
+                                                       env=self.env,
+                                                       loop=self.loop,
+                                                       stdout_callback=self._stdout_cb,
+                                                       terminated_callback=self._terminated_cb)
+
+    def _stdout_cb(self, data):
+        self._log.debug(f"_stdout_cb({data})")
+        with self._lock:
+            self._stdout.extend(data)
+
+    def read(self):
+        self._log.debug(f"read()")
+        with self._lock:
+            data = self._stdout.copy()
+            self._stdout.clear()
+        self._log.debug(f"read() returns {data}")
+        return data
+
+    def _terminated_cb(self, rc):
+        self._log.debug(f"_terminated_cb({rc})")
+        self.return_code = rc
+
+    def start(self):
+        self._log.debug(f"start()")
+        self.process.start()
+
+    def cleanup(self):
+        self._log.debug(f"cleanup()")
+        if self.process and self.process.running:
+            self.process.terminate(kill_delay=0.1)
+
+    def __exit__(self, __exc_type: typing.Type[BaseException], __exc_value: BaseException,
+                 __traceback: types.TracebackType) -> bool:
+        self._log.debug(f"__exit__({__exc_type}, {__exc_value}, {__traceback})")
+        self.cleanup()
+        return False
+
+
+def replace_text_in_file(filename: str, text: str, replacement: str):
+    # Read in the file
+    with open(filename, 'r') as file:
+        filedata = file.read()
+
+    # Replace the target string
+    filedata = filedata.replace(text, replacement)
+
+    # Write the file out again
+    with open(filename, 'w') as file:
+        file.write(filedata)
+
+
+class tempdir(object):
+    """Sets the cwd within the context
+
+    Args:
+        path (Path): The path to the cwd
+    """
+    def __init__(self, cd: bool = False):
+        self.cd = cd
+        self.tempdir = tempfile.TemporaryDirectory()
+        self.path = self.tempdir.name
+        self.origin = pathlib.Path().absolute()
+        self.configfile = os.path.join(self.path, "config")
+
+    def setup_files(self):
+        shutil.copy(os.path.join(module_dir, "reticulum_test_config"), self.configfile)
+        port1 = random.randint(30000, 65000)
+        port2 = port1 + 1
+        replace_text_in_file(self.configfile, "22222", str(port1))
+        replace_text_in_file(self.configfile, "22223", str(port2))
+
+
+    def __enter__(self):
+        self.setup_files()
+        if self.cd:
+            os.chdir(self.path)
+
+        return self.path
+
+    def __exit__(self, exc, value, tb):
+        if self.cd:
+            os.chdir(self.origin)
+        self.tempdir.__exit__(exc, value, tb)
+
+
+def test_config_and_cleanup():
+    td = None
+    with tests.helpers.tempdir() as td:
+        assert os.path.isfile(os.path.join(td, "config"))
+        with open(os.path.join(td, "config"), 'r') as file:
+            filedata = file.read()
+        assert filedata.index("acehoss test config") > 0
+        with pytest.raises(ValueError):
+            filedata.index("22222")
+    assert not os.path.exists(os.path.join(td, "config"))