`catkin clean` fails when extended workspace does not exist

[v4hn]

as far as I know catkin clean is basically a nicer rm -rf build devel install logs (reading the folder names from the configuration). However, if the parent workspace does not exist (e.g., because one cleans all workspaces in order to build them all again from scratch), catkin clean will abort with a ValueError:

ValueError: Resultspace path '[parent workspace path]' does not exist.