feat: add 'CompactPopupWidget' container widget

Makes it easy to write widgets which can have a compact
representation with LED-like global state indicator,
with the possibility to display a popup dialog with more
complete UI

tests/unit_tests/test_compact_popup_widget.py

@@ -0,0 +1,66 @@
+# pylint: skip-file
+from unittest import mock
+
+import pytest
+from qtpy.QtCore import Qt
+from qtpy.QtWidgets import QSizePolicy, QVBoxLayout, QWidget
+
+from bec_widgets.qt_utils.compact_popup import CompactPopupWidget
+
+
+class ContainedWidget(QWidget):
+    def __init__(self, parent):
+        super().__init__(parent)
+
+
+class TestCompactPopupWidget(CompactPopupWidget):
+    def __init__(self):
+        super().__init__(layout=QVBoxLayout)
+
+        self.contained = QWidget(self)
+        self.addWidget(self.contained)
+        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Minimum)
+
+
+@pytest.fixture
+def compact_popup(qtbot):
+    widget = TestCompactPopupWidget()
+    qtbot.addWidget(widget)
+    widget.show()
+    qtbot.wait_until(widget.isVisible)
+    yield widget
+
+
+def test_widget_closing(qtbot, compact_popup):
+    with mock.patch.object(compact_popup.contained, "close") as close_method:
+        compact_popup.close()
+    qtbot.waitUntil(lambda: not compact_popup.isVisible(), timeout=1000)
+    close_method.assert_called_once()
+
+
+def test_size_policy(compact_popup):
+    csp = compact_popup.sizePolicy()
+    assert csp.horizontalPolicy() == QSizePolicy.Expanding
+    assert csp.verticalPolicy() == QSizePolicy.Minimum
+    compact_popup.setSizePolicy(QSizePolicy.Minimum, QSizePolicy.Expanding)
+    csp = compact_popup.sizePolicy()
+    assert csp.horizontalPolicy() == QSizePolicy.Minimum
+    assert csp.verticalPolicy() == QSizePolicy.Expanding
+    compact_popup.compact = True
+    csp = compact_popup.sizePolicy()
+    assert csp.horizontalPolicy() == QSizePolicy.Fixed
+    assert csp.verticalPolicy() == QSizePolicy.Fixed
+    compact_popup.compact = False
+    csp = compact_popup.sizePolicy()
+    assert csp.horizontalPolicy() == QSizePolicy.Minimum
+    assert csp.verticalPolicy() == QSizePolicy.Expanding
+
+
+def test_open_full_view(qtbot, compact_popup):
+    qtbot.waitUntil(compact_popup.container.isVisible, timeout=1000)
+    compact_popup.compact = True
+    qtbot.waitUntil(compact_popup.compact_view.isVisible, timeout=1000)
+    qtbot.mouseClick(compact_popup.compact_show_popup, Qt.LeftButton)
+    qtbot.waitUntil(compact_popup.container.isVisible, timeout=1000)
+    compact_popup._popup_window.close()
+    qtbot.waitUntil(lambda: not compact_popup.container.isVisible(), timeout=1000)