Add helpful error when we forget to patch the GUI

Author: facelessuser

rummage/lib/gui/rummage_dialog.py

@@ -36,6 +36,12 @@
 from .actions import export_csv
 from .actions import fileops
 from .actions import updates
+try:
+    from .gui import GUI_PATCHED  # noqa: F401
+except ImportError:
+    # We forgot to patch the GUI, which will cause issues,
+    # so raise a helpful error that points us to what we need to do.
+    raise RuntimeError("GUI has not been patched. Please run tools/gui_patch.py")
 from .generic_dialogs import errormsg, yesno, infomsg
 from .app.custom_app import debug, error, get_log_file
 from .controls import custom_statusbar

tools/gui_patch.py

@@ -10,7 +10,7 @@
 # Add collapsible pane replacement
 text = re.sub(
     r'^((?:import|from)(?! \.controls\.collapsible_pane).*?)(\r?\n){2}',
-    r'\1\2from .controls.collapsible_pane import CollapsiblePane\2\2',
+    r'\1\2from .controls.collapsible_pane import CollapsiblePane\2\2GUI_PATCHED = True\2\2',
     text,
     flags=re.M
 )