Added improved models

src/cpl_reactive_extensions/subscription.py

@@ -0,0 +1,74 @@
+from __future__ import annotations
+
+from typing import Union, Callable, Optional
+
+from cpl_reactive_extensions.abc.unsubscribable import Unsubscribable
+
+
+class Subscription(Unsubscribable):
+    def __init__(self, initial_teardown: Optional[Callable] = None):
+        Unsubscribable.__init__(self)
+
+        self._initial_teardown = initial_teardown
+
+        self._closed = False
+        self._subscriptions = []
+
+        self._parentage: list[Subscription] = []
+        self._finalizers: list[Subscription] = []
+
+    @property
+    def closed(self) -> bool:
+        return self._closed
+
+    def _add_parent(self, parent: Subscription):
+        self._parentage.append(parent)
+
+    def _has_parent(self, parent: Subscription) -> bool:
+        return parent in self._parentage
+
+    def _exec_finalizer(self, finalizer: Union[Callable, Unsubscribable]):
+        if isinstance(finalizer, Callable):
+            finalizer()
+        else:
+            finalizer.unsubscribe()
+
+    def unsubscribe(self):
+        if not self._closed:
+            self._closed = True
+
+        for parent in self._parentage:
+            parent.remove(self)
+
+        if self._initial_teardown is not None:
+            try:
+                self._initial_teardown()
+            except Exception as e:
+                print(e)
+
+        for finalizer in self._finalizers:
+            try:
+                self._exec_finalizer(finalizer)
+            except Exception as e:
+                print(e)
+
+        self._subscriptions.clear()
+
+    def add(self, tear_down: Union[Subscription, Unsubscribable]):
+        if tear_down is None or tear_down == self:
+            return
+
+        if self.closed:
+            self._exec_finalizer(tear_down)
+            return
+
+        if isinstance(tear_down, Subscription):
+            if tear_down.closed or tear_down._has_parent(self):
+                return
+
+            tear_down._add_parent(self)
+
+        self._subscriptions.append(tear_down)
+
+    def remove(self, tear_down: Union[Subscription, Unsubscribable]):
+        self._subscriptions.remove(tear_down)