Listing GuiPrivate unconditionally in QET_COMPONENTS breaks the whole
Qt5 configure: find_package(Qt5 COMPONENTS GuiPrivate) looks for a
Qt5GuiPrivateConfig.cmake that has never existed - Qt5 creates the
Qt5::GuiPrivate target implicitly together with Gui. Only Qt6 requires
(and provides) the explicit component.
Move the request into a QT_VERSION_MAJOR-guarded find_package after the
main one, both for the application and for tests/catch (whose targets
link Qt::GuiPrivate via QET_PRIVATE_LIBRARIES). Fixes the msys2/Qt5
Windows CI configure failure:
"Could not find a package configuration file provided by Qt5GuiPrivate".
Verified: Qt 6.11 configure passes and the Qt6::GuiPrivate target is
created (the private-module warning now fires from the guarded call).
The Qt5 path simply no longer requests the component, restoring the
pre-existing implicit behaviour.
Add a no-KF5 Catch regression test that leaves a KAutoSaveFile-compatible backup behind from a child process, then verifies stale-file discovery, stale-lock recovery, reading, and cleanup.
Assisted-by: pi coding agent / Mika (OpenAI GPT-5.5)
Dieter Mayer