Add in-app speaker discovery and connection guide

tests/test_discovery.py

@@ -0,0 +1,69 @@
+"""Discovery fixtures include the owner's actual unnamed FE40 advertisement."""
+
+import asyncio
+import queue
+import sys
+import types
+import unittest
+from unittest.mock import AsyncMock, patch
+
+from controller.discovery import ScanWorker, Speaker, scan_speakers, selected_address
+
+
+def advertisement(name, address, uuids=()):
+    return (
+        types.SimpleNamespace(name=name, address=address),
+        types.SimpleNamespace(local_name=name, service_uuids=list(uuids)),
+    )
+
+
+class DiscoveryTests(unittest.TestCase):
+    def test_unnamed_model_advertisement_and_named_speaker_are_selectable(self):
+        found = {
+            "unnamed": advertisement(
+                None, "12:34:56:78:9A:BC", ["0000fe40-0000-1000-8000-00805f9b34fb"]
+            ),
+            "named": advertisement("[AV] MX-T40", "12:34:56:78:9A:BD"),
+            "unrelated": advertisement(
+                "Headphones", "12:34:56:78:9A:BE", ["0000ffa0-0000-1000-8000-00805f9b34fb"]
+            ),
+        }
+        discover = AsyncMock(return_value=found)
+        with patch.dict(
+            sys.modules,
+            {"bleak": types.SimpleNamespace(BleakScanner=types.SimpleNamespace(discover=discover))},
+        ):
+            speakers = asyncio.run(scan_speakers(timeout=3))
+        self.assertEqual(len(speakers), 2)
+        self.assertEqual(
+            {speaker.address for speaker in speakers}, {"12:34:56:78:9A:BC", "12:34:56:78:9A:BD"}
+        )
+        unnamed = next(speaker for speaker in speakers if speaker.address.endswith("BC"))
+        self.assertEqual(unnamed.name, "MX-T40 (model advertisement)")
+        self.assertIn(unnamed.address, unnamed.label)
+        discover.assert_awaited_once_with(timeout=3, return_adv=True)
+
+    def test_choice_resolves_to_address_and_preserves_manual_input(self):
+        speaker = Speaker("12:34:56:78:9A:BC", "MX-T40")
+        self.assertEqual(selected_address(speaker.label, [speaker]), speaker.address)
+        self.assertEqual(selected_address("  12:34:56:78:9A:BD  ", [speaker]), "12:34:56:78:9A:BD")
+
+    def test_identical_names_remain_distinguishable(self):
+        speakers = [Speaker("12:34:56:78:9A:BC", "MX-T40"), Speaker("12:34:56:78:9A:BD", "MX-T40")]
+        self.assertNotEqual(speakers[0].label, speakers[1].label)
+        self.assertEqual(selected_address(speakers[1].label, speakers), speakers[1].address)
+
+    def test_scan_error_is_delivered_to_gui_queue(self):
+        events = queue.Queue()
+        with patch(
+            "controller.discovery.scan_speakers",
+            AsyncMock(side_effect=RuntimeError("Bluetooth is off")),
+        ):
+            ScanWorker(events).run()
+        self.assertEqual(events.get_nowait(), ("scan_error", "Bluetooth is off"))
+
+    def test_empty_scan_has_a_result_event(self):
+        events = queue.Queue()
+        with patch("controller.discovery.scan_speakers", AsyncMock(return_value=[])):
+            ScanWorker(events).run()
+        self.assertEqual(events.get_nowait(), ("scan_results", []))