BUG: Fix incorrect enter/exit called after scripted module reload

When a scripted loadable module was reloaded using slicer.util.reloadScriptedModule, pythonSource was not changed in qSlicerScriptedLoadableModuleWidget. As a result, the previous enter/exit methods continued to be used by the scripted module.

Fixed by making setPythonSource accessible in Python, and using it to instantiate the new widget object.

Fix #7211

Base/Python/slicer/util.py

@@ -1372,10 +1372,12 @@ def reloadScriptedModule(moduleName):
     for item in items:
         parent.layout().removeItem(item)
 
-    # create new widget inside existing parent
-    widget = eval("reloaded_module.%s(parent)" % widgetName)
+    # Creates new widget at slicer.modules.{widgetName}.
+    # Also ensures that qSlicerScriptedLoadableModuleWidget has references to updated enter/exit/setup methods.
+    parent.setPythonSource(filePath)
+    # get new widget
+    widget = getattr(slicer.modules, widgetName)
     widget.setup()
-    setattr(slicer.modules, widgetName, widget)
 
     return reloaded_module
 

Base/QTGUI/qSlicerScriptedLoadableModuleWidget.h

@@ -44,8 +44,8 @@ class Q_SLICER_BASE_QTGUI_EXPORT qSlicerScriptedLoadableModuleWidget
   qSlicerScriptedLoadableModuleWidget(QWidget * parentWidget=nullptr);
   ~qSlicerScriptedLoadableModuleWidget() override;
 
-  QString pythonSource()const;
-  bool setPythonSource(const QString& filePath, const QString& className = QLatin1String(""));
+  Q_INVOKABLE QString pythonSource()const;
+  Q_INVOKABLE bool setPythonSource(const QString& filePath, const QString& className = QLatin1String(""));
 
   /// Convenience method allowing to retrieve the associated scripted instance
   Q_INVOKABLE PyObject* self() const;