fix: stop sketcher status bar from resizing the window

rayforge/ui_gtk/shared/status_bar.py

@@ -4,10 +4,32 @@
 
 
 class StatusBar(Gtk.Box):
+    """
+    Displays context sensitive shortcut hints in a single row.
+
+    Entries are added and removed whenever tool state changes, so their
+    combined width varies. The row is therefore hosted in a scrolled
+    window with an EXTERNAL horizontal policy: the bar never propagates
+    the content width into the window's size request. Otherwise such
+    state changes would resize the entire window while dragging in the
+    sketcher (observed on macOS, see issue #385). If the bar is too
+    narrow, entries are clipped instead of widening the window.
+    """
+
     def __init__(self, **kwargs):
-        super().__init__(orientation=Gtk.Orientation.HORIZONTAL, **kwargs)
+        super().__init__(orientation=Gtk.Orientation.VERTICAL, **kwargs)
         self.add_css_class("status-bar")
-        self.set_spacing(24)
+
+        self._content = Gtk.Box(
+            orientation=Gtk.Orientation.HORIZONTAL, spacing=24
+        )
+        self._scroller = Gtk.ScrolledWindow()
+        self._scroller.set_policy(
+            Gtk.PolicyType.EXTERNAL, Gtk.PolicyType.NEVER
+        )
+        self._scroller.set_child(self._content)
+        self._scroller.set_hexpand(True)
+        self.append(self._scroller)
 
     def add_shortcut_entry(
         self,
@@ -19,19 +41,19 @@ def add_shortcut_entry(
         shortcut = Shortcut(
             keys=keys, description=description, separator=separator
         )
-        self.append(shortcut)
+        self._content.append(shortcut)
 
     def add_separator(self):
         """Add a visual separator between shortcuts."""
         separator = Gtk.Box(orientation=Gtk.Orientation.VERTICAL)
         separator.set_size_request(1, 16)
         separator.add_css_class("separator")
         separator.get_style_context().add_class("separator")
-        self.append(separator)
+        self._content.append(separator)
 
     def clear(self):
         """Remove all shortcuts from the status bar."""
-        child = self.get_first_child()
+        child = self._content.get_first_child()
         while child is not None:
-            self.remove(child)
-            child = self.get_first_child()
+            self._content.remove(child)
+            child = self._content.get_first_child()

tests/ui_gtk/shared/test_status_bar.py

@@ -0,0 +1,90 @@
+# flake8: noqa: E402
+"""UI tests for the shared StatusBar widget."""
+
+import gi
+
+gi.require_version("Gtk", "4.0")
+
+from gi.repository import Gtk
+
+import pytest
+
+from rayforge.ui_gtk.shared.status_bar import StatusBar
+
+
+def _measure_width(widget: Gtk.Widget) -> int:
+    minimum, _, _, _ = widget.measure(Gtk.Orientation.HORIZONTAL, -1)
+    return minimum
+
+
+def _measure_height(widget: Gtk.Widget) -> int:
+    minimum, _, _, _ = widget.measure(Gtk.Orientation.VERTICAL, -1)
+    return minimum
+
+
+def _count_children(box: Gtk.Box) -> int:
+    count = 0
+    child = box.get_first_child()
+    while child is not None:
+        count += 1
+        child = child.get_next_sibling()
+    return count
+
+
+@pytest.mark.ui
+def test_entries_are_added_to_content_row():
+    bar = StatusBar()
+    bar.add_shortcut_entry(["Space"], "Pan", separator="")
+    bar.add_shortcut_entry(["Shift", "Tab"], "Constrain to Axis")
+    assert _count_children(bar._content) == 2
+
+
+@pytest.mark.ui
+def test_clear_removes_all_entries():
+    bar = StatusBar()
+    bar.add_shortcut_entry(["Space"], "Pan", separator="")
+    bar.add_separator()
+    bar.add_shortcut_entry(["Shift"], "Constrain to Axis")
+    assert _count_children(bar._content) == 3
+
+    bar.clear()
+    assert _count_children(bar._content) == 0
+
+
+@pytest.mark.ui
+def test_min_width_does_not_follow_content():
+    """
+    The status bar must not propagate the width of its shortcut entries
+    into the window's size request. Entry changes during sketch drags
+    would otherwise resize the whole window (issue #385).
+    """
+    bar = StatusBar()
+    empty_width = _measure_width(bar)
+
+    bar.add_shortcut_entry(["Space"], "Pan", separator="")
+    idle_width = _measure_width(bar)
+
+    bar.add_shortcut_entry(
+        ["Shift", "Doubleclick"],
+        "Select Connected with a very long description",
+    )
+    bar.add_shortcut_entry(
+        ["Ctrl", "Shift", "Alt", "Super"],
+        "Yet another very long shortcut description",
+    )
+    assert _count_children(bar._content) == 3
+    assert idle_width == empty_width
+    assert _measure_width(bar) == idle_width
+
+
+@pytest.mark.ui
+def test_height_follows_content():
+    bar = StatusBar()
+    empty_height = _measure_height(bar)
+
+    bar.add_shortcut_entry(["Space"], "Pan", separator="")
+    idle_height = _measure_height(bar)
+    assert idle_height > empty_height
+
+    bar.clear()
+    assert _measure_height(bar) == empty_height