fix(commons): deduplicate logic to keep behavior consistent [#14]

[rmlibre]

Description

Detailed in (#14)

Expected behavior

Detailed in (#14)

Remediations

• Make changes compatible with existing usage

The __contains__ logic also needed to be fixed to allow the simplification in this commit. Checking hasattr wasn't a limiting enough condition, as anything in the class dictionary would also return True. This led to errors when using namespaces as modules, because they'd take in attribute names like __doc__ which would proc a PermissionError in frozen classes.

• Test that buggy behavior is no longer present

This that the frozen functionality is consistently applied across the various interfaces & class hierarchies.

aiootp/tests/test_namespace_classes.py

Lines 307 to 321 in 70cd055

	async def test_frozen_state_is_enforced(self) -> None:
	problem = ( # fmt: skip
	"A mutation was allowed on a frozen object."
	)
	if not self._frozen:
	return
	obj = self._type(self._items)
	with Ignore(PermissionError, if_else=violation(problem)):
	obj.__init__(self._items)
	obj = self._type(self._items)
	for name, value in self._items.items():
	with Ignore(PermissionError, if_else=violation(problem)):
	obj[name] = value

Resolution related to (#9, #11, #14)