In all my Swift packages where I use subfolders in the
Sources/MyProject folder, Xcode does show errors immediately for all top-level files in
Sources/MyProject while typing (this feature is called "live issues" I think), but not e.g. for a Swift file in a subfolder i.e.
Sources/MyProject/MySubfolder. Only when building, errors are shown in such a file.
This problem occurs with Xcode version 13.1 (13A1030d) on macOS 12.0.1 (21A559) on ARM, and I am pretty sure that this is a new thing. Can anyone acknowledge that this is a problem? Is it a problem of Xcode, and/or can I somehow resolve this issue?