Make checking for unknown commandline args configurable in the config module.

Introducing commandline args lead to errors when passing arguments to pytest, which were in turn passed to the code and causing errors because they were not recognised. This change only runs the check for known arguments from the main() routine while other imports won't cause a check.

beeref/__main__.py

@@ -22,10 +22,9 @@ import sys
 
 from PyQt6 import QtCore, QtGui, QtWidgets
 
-from beeref.config import commandline_args
+from beeref.config import CommandlineArgs
 from beeref.view import BeeGraphicsView
 
-
 logger = logging.getLogger('BeeRef')
 
 
@@ -69,6 +68,7 @@ def handle_sigint(signum, frame):
 
 
 def main():
+    commandline_args = CommandlineArgs(with_check=True)
     logging.basicConfig(level=getattr(logging, commandline_args.loglevel))
     app = QtWidgets.QApplication(sys.argv)
     bee = BeeRefMainWindow(app)  # NOQA:F841

beeref/config.py

@@ -34,4 +34,31 @@ parser.add_argument(
     action='store_true',
     help='draw debug shapes for bounding rects and interactable areas')
 
-commandline_args = parser.parse_args()
+
+class CommandlineArgs():
+    """Wrapper around argument parsing.
+
+    Checking for unknown arugments is configurable so that it can be
+    deliberately enabled from the main() function while ignored for
+    other imports. This is a singleton so that arguments are only
+    parsed once.
+    """
+
+    _instance = None
+
+    def __new__(cls, *args, **kwargs):
+        if not cls._instance:
+            cls._instance = super().__new__(cls, *args, **kwargs)
+        return cls._instance
+
+    def __init__(self, with_check=False):
+        if with_check:
+            self._args = parser.parse_args()
+        else:
+            self._args = parser.parse_known_args()[0]
+
+    def __getattribute__(self, name):
+        if name == '_args':
+            return super().__getattribute__(name)
+        else:
+            return getattr(self._args, name)

beeref/items.py

@@ -24,9 +24,10 @@ from PyQt6.QtCore import Qt
 from PyQt6.QtWidgets import QGraphicsItem
 
 from beeref import commands
-from beeref.config import commandline_args
+from beeref.config import CommandlineArgs
 
 
+commandline_args = CommandlineArgs()
 logger = logging.getLogger('BeeRef')
 
 

beeref/view.py

@@ -19,12 +19,14 @@ from PyQt6 import QtCore, QtGui, QtWidgets
 from PyQt6.QtCore import Qt
 
 from beeref import commands
-from beeref.config import commandline_args
+from beeref.config import CommandlineArgs
 from beeref import fileio
 from beeref.gui import BeeProgressDialog, WelcomeOverlay
 from beeref.items import BeePixmapItem
 from beeref.scene import BeeGraphicsScene
 
+
+commandline_args = CommandlineArgs()
 logger = logging.getLogger('BeeRef')