🐛 | Make SearchWorker tests robust to Qt fallback environments

Replace SearchWorker signal .connect() with mock.MagicMock to handle
the case where the player module Signal binding is a plain function
(import fallback when PySide6 is unavailable in headless CI).
The MagicMock captures .emit() calls and works across all environments:
real Qt, conftest stubs, and player.py fallback paths.

tests/test_player_helpers.py

@@ -5,6 +5,7 @@ import struct
 import math
 import tempfile
 from pathlib import Path
+from unittest import mock
 
 import pytest
 
@@ -345,20 +346,28 @@ class TestTmpDir:
 # ── SearchWorker (TEST_MODE) ─────────────────────────────────────────────────
 
 class TestSearchWorkerTestMode:
-    """Tests for SearchWorker.run() with TEST_MODE enabled."""
+    """Tests for SearchWorker.run() with TEST_MODE enabled.
+
+    Uses ``mock.MagicMock`` to capture signal emissions instead of
+    ``.connect()`` because the player module's ``Signal`` binding may
+    be a plain function (the import fallback when PySide6 is unavailable)
+    that does not have a ``.connect()`` method.
+    """
 
     def test_returns_dummy_results_in_test_mode(self, monkeypatch):
         """With TEST_MODE=True, SearchWorker returns 5 dummy songs."""
         monkeypatch.setattr("player.TEST_MODE", True)
         from player import SearchWorker
 
-        results = []
         worker = SearchWorker("test query")
-        worker.results_ready.connect(results.append)
+        # Use a MagicMock to capture signal emissions — works with both
+        # real Signal, stub _Signal, and fallback lambda.
+        mock_signal = mock.MagicMock()
+        worker.results_ready = mock_signal
         worker.run()
 
-        assert len(results) == 1
-        data = results[0]
+        mock_signal.emit.assert_called_once()
+        data = mock_signal.emit.call_args[0][0]
         assert "songs" in data
         assert "videos" in data
         assert len(data["songs"]) == 5
@@ -370,12 +379,14 @@ class TestSearchWorkerTestMode:
         monkeypatch.setattr("player.TEST_MODE", True)
         from player import SearchWorker
 
-        results = []
         worker = SearchWorker("test query")
-        worker.results_ready.connect(lambda r: results.append(r))
+        mock_signal = mock.MagicMock()
+        worker.results_ready = mock_signal
         worker.run()
 
-        song = results[0]["songs"][0]
+        mock_signal.emit.assert_called_once()
+        data = mock_signal.emit.call_args[0][0]
+        song = data["songs"][0]
         assert "videoId" in song
         assert "title" in song
         assert "artists" in song