feat: add loader/helper for widget plugins

tests/unit_tests/test_bec_plugin_helper.py

@@ -0,0 +1,61 @@
+from importlib.machinery import FileFinder, SourceFileLoader
+from types import ModuleType
+from unittest import mock
+
+from bec_widgets.utils.bec_plugin_helper import BECWidget, _all_widgets_from_all_submods
+
+
+def test_all_widgets_from_module_no_submodules():
+    """
+    Test _all_widgets_from_all_submodules with a module that has no submodules.
+    """
+    module = mock.MagicMock(spec=ModuleType)
+
+    with mock.patch(
+        "bec_widgets.utils.bec_plugin_helper._get_widgets_from_module",
+        return_value={"TestWidget": BECWidget},
+    ):
+        widgets = _all_widgets_from_all_submods(module)
+
+    assert widgets == {"TestWidget": BECWidget}
+
+
+def test_all_widgets_from_module_with_submodules():
+    """
+    Test _all_widgets_from_all_submodules with a module that has submodules.
+    """
+    module = mock.MagicMock()
+    module.__path__ = ["path/to/module"]
+
+    submodule = mock.MagicMock()
+    submodule.__loader__ = mock.MagicMock(spec=SourceFileLoader)
+
+    finder_mock = mock.MagicMock(spec=FileFinder, return_value=True)
+    with (
+        mock.patch(
+            "pkgutil.iter_modules",
+            return_value=[mock.MagicMock(module_finder=finder_mock, name="submodule")],
+        ),
+        mock.patch("importlib.util.module_from_spec", return_value=submodule),
+        mock.patch(
+            "bec_widgets.utils.bec_plugin_helper._get_widgets_from_module",
+            side_effect=[{"TestWidget": BECWidget}, {"SubWidget": BECWidget}],
+        ),
+    ):
+        widgets = _all_widgets_from_all_submods(module)
+
+    assert widgets == {"TestWidget": BECWidget, "SubWidget": BECWidget}
+
+
+def test_all_widgets_from_module_no_widgets():
+    """
+    Test _all_widgets_from_all_submodules with a module that has no widgets.
+    """
+    module = mock.MagicMock()
+
+    with mock.patch(
+        "bec_widgets.utils.bec_plugin_helper._get_widgets_from_module", return_value={}
+    ):
+        widgets = _all_widgets_from_all_submods(module)
+
+    assert widgets == {}