lib: Give TagStores functions for saving and restoring

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

lib/tagstore.py

@@ -10,6 +10,10 @@ class TagStore:
         self.Added = publisher.Publisher()
         self.Removed = publisher.Publisher()
 
+    def __getstate__(self):
+        with self.lock:
+            return { "store" : self.store }
+
     def __get_tag__(self, name):
         with self.lock:
             if (t := self.store.get(name)) != None:
@@ -19,6 +23,12 @@ class TagStore:
         self.Added.publish(t)
         return t
 
+    def __setstate__(self, state):
+        self.store = state["store"]
+        self.lock = threading.Lock()
+        self.Added = publisher.Publisher()
+        self.Removed = publisher.Publisher()
+
     def add(self, name, track=None):
         t = self.__get_tag__(name.strip())
         if track:

lib/test_tagstore.py

@@ -67,3 +67,17 @@ class TestTagStore(unittest.TestCase):
         self.assertNotIn(tag.name, store.store.keys())
         self.assertEqual(store.Added.subscribers, set())
         self.assertEqual(store.Removed.subscribers, set())
+
+    def test_tag_store_state(self):
+        store = tagstore.TagStore()
+        tag = store.add("test", 1)
+
+        state = store.__getstate__()
+        self.assertEqual(set(state.keys()), set([ "store" ]))
+
+        store.__dict__.clear()
+        store.__setstate__(state)
+        self.assertEqual(store.store, { "test" : tag })
+        self.assertIsInstance(store.lock, type(threading.Lock()))
+        self.assertIsInstance(store.Added, publisher.Publisher)
+        self.assertIsInstance(store.Removed, publisher.Publisher)