v0.1.5: sidebar playlist tree auto-scrolls when dragging near its edges

tests/test_round24.py

@@ -0,0 +1,82 @@
+"""Round 24: sidebar drag auto-scroll.
+
+Dragging a playlist (or tracks) near the top/bottom edge of the sidebar's
+playlist tree scrolls the tree so off-screen rows can be reached. Same root
+cause and fix as the track table's Round 13: our dragMoveEvent accepts the
+event itself, so Qt's built-in autoscroll never runs. The direction helper
+(autoscroll_direction) is shared with the table and already covered by
+test_round13.
+"""
+
+from PyQt6.QtCore import QPoint
+
+from lintunes.models import Library, Track
+from lintunes.library_manager import LibraryManager
+from lintunes.gui.sidebar import PlaylistTree
+
+
+def _tree(qapp, tmp_path, playlists=0):
+    library = Library(tracks={1: Track(track_id=1, name="One")})
+    manager = LibraryManager(library, tmp_path)
+    tree = PlaylistTree(manager)
+    for i in range(playlists):
+        manager.create_playlist(f"playlist {i}")
+    # Small viewport: enough rows that the scrollbar gets a real range (the
+    # view re-derives the range itself, so a manual setRange doesn't stick;
+    # show() forces the polish/layout pass that computes it).
+    tree.resize(200, 100)
+    tree.show()
+    return tree
+
+
+class TestAutoscrollTick:
+    def test_tick_scrolls_by_direction(self, qapp, tmp_path):
+        tree = _tree(qapp, tmp_path, playlists=60)
+        bar = tree.verticalScrollBar()
+        assert bar.maximum() > 20  # real range from the rows
+        bar.setValue(10)
+
+        tree._autoscroll_dir = 1
+        tree._autoscroll_tick()
+        assert bar.value() == 11
+
+        tree._autoscroll_dir = -1
+        tree._autoscroll_tick()
+        assert bar.value() == 10
+
+    def test_tick_stops_at_the_end(self, qapp, tmp_path):
+        tree = _tree(qapp, tmp_path, playlists=60)
+        bar = tree.verticalScrollBar()
+        bar.setValue(bar.maximum())  # already at the bottom
+
+        tree._autoscroll_dir = 1
+        tree._autoscroll_timer.start()
+        tree._autoscroll_tick()
+
+        assert bar.value() == bar.maximum()
+        assert not tree._autoscroll_timer.isActive()
+
+
+class TestUpdateAutoscroll:
+    def test_edge_starts_timer(self, qapp, tmp_path):
+        tree = _tree(qapp, tmp_path)
+        tree.resize(200, 300)
+        tree._update_autoscroll(QPoint(10, 5), accepted=True)
+        assert tree._autoscroll_dir == -1
+        assert tree._autoscroll_timer.isActive()
+
+    def test_rejected_drop_keeps_timer_off(self, qapp, tmp_path):
+        tree = _tree(qapp, tmp_path)
+        tree.resize(200, 300)
+        tree._update_autoscroll(QPoint(10, 5), accepted=False)
+        assert tree._autoscroll_dir == 0
+        assert not tree._autoscroll_timer.isActive()
+
+    def test_stop_autoscroll_resets(self, qapp, tmp_path):
+        tree = _tree(qapp, tmp_path)
+        tree._autoscroll_dir = 1
+        tree._autoscroll_timer.start()
+        tree._stop_autoscroll()
+        assert tree._autoscroll_dir == 0
+        assert tree._autoscroll_pos is None
+        assert not tree._autoscroll_timer.isActive()