menu: do not close on the panel's own scrolling

The dismiss-on-scroll listener is on the capture phase, because `scroll`
does not bubble — so it also heard the menu scrolling itself, and a long
tracklist closed the moment it was wheeled. Filter on the event's origin.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/packages/meshbay-hub/tests/test_menu_scroll.py b/packages/meshbay-hub/tests/test_menu_scroll.py
new file mode 100644
index 0000000..5b680a4
--- /dev/null
+++ b/packages/meshbay-hub/tests/test_menu_scroll.py
@@ -0,0 +1,76 @@
+"""
+A pop-up menu taller than the window can be scrolled without dismissing itself.
+
+`.ctx-menu` is `overflow-y: auto` under a `max-height`, and a playlist's
+tracklist expands *inside* it — sixty tracks is three times the panel's height,
+so scrolling is the only way to reach most of them. Both ways of scrolling it
+closed it instead: the wheel, and dragging its own scrollbar. Reported against
+"remove a track", where the menu vanished before a track could be clicked.
+
+`scroll` does not bubble, so the listener that dismisses the menu on a page
+scroll is on the capture phase — and capture is equally what made it hear the
+panel's own scrolling on the way down.
+
+Measured, not read. `playlist_ui_probe.py` drives the same menu and cannot see
+this: it reaches every row with `.click()`, which scrolls nothing at all.
+
+The last two cases are the ones that must keep closing the menu, and they are
+why the fix is a filter on the event's origin rather than a removed listener.
+"""
+
+import json
+import shutil
+import subprocess
+import sys
+from pathlib import Path
+
+import pytest
+
+HARNESS = Path(__file__).parent / "harness" / "menu_scroll_probe.py"
+
+
+@pytest.fixture(scope="module")
+def cases():
+    if shutil.which("google-chrome") is None:
+        pytest.skip("Chrome is not available")
+    proc = subprocess.run([sys.executable, str(HARNESS)],
+                          capture_output=True, text=True, timeout=90)
+    data = json.loads(proc.stdout)
+    assert "error" not in data, f"probe failed: {proc.stdout}{proc.stderr}"
+    return {c["case"]: c for c in data["cases"]}
+
+
+def test_the_fixture_actually_overflows(cases):
+    # A menu that fits measures nothing, and would let every assertion below
+    # pass with the fix removed.
+    c = cases["the panel is scrollable at all"]
+    assert c["overflows"], f"60 rows did not overflow the panel: {c}"
+
+
+def test_the_wheel_scrolls_the_menu_instead_of_closing_it(cases):
+    c = cases["scrolled inside the menu"]
+    assert c["stillOpen"], "the menu closed when it was scrolled"
+    assert c["scrollTop"] == 200, "the menu did not scroll"
+
+
+def test_dragging_the_menus_own_scrollbar_does_not_close_it(cases):
+    c = cases["pressed the menu scrollbar and dragged"]
+    assert c["stillOpen"], "pressing the scrollbar closed the menu"
+    assert c["scrollTop"] == 400, "the drag did not scroll"
+
+
+def test_reaching_the_end_does_not_scroll_the_page_behind(cases):
+    # Chained to the page, that overscroll *is* a page scroll, and a page
+    # scroll closes the menu on purpose — the same symptom by another door.
+    assert cases["the panel is scrollable at all"]["overscrollBehaviorY"] == "contain"
+
+
+def test_a_press_outside_still_closes_it(cases):
+    assert cases["pressed outside the menu"]["closed"]
+
+
+def test_scrolling_the_page_still_closes_it(cases):
+    # Not optional: the menu is `position: fixed` and the media grids scroll
+    # under a sticky toolbar, so a menu that survives leaves itself pointing at
+    # an album that has moved.
+    assert cases["scrolled the page underneath"]["closed"]