Moving the checkout to another path or account left three kinds of stale
state behind (issue #142):
- configure.py kept the previous home's default prefix. A saved prefix that
was exactly <previous home>/.darling now follows the current host home; a
user-chosen prefix is kept, and one inside the previous home is reported
with the --prefix escape hatch.
- build/runtime/build was an absolute symlink, so it dangled after a move and
the "not link.exists()" guard treated the dangling entry as absent. It is
now a relative link and an absolute or dangling leftover is replaced. A
real directory at that path is reported and left untouched.
- A CMake cache generated for another source directory made the build fail
with permission errors against the old path. configure.py now reports the
cache and the exact directory to remove, and never deletes it itself.
Patches are rendered at prepare.py time, so the report also points at the
re-render path. Documents the moved-checkout steps and the opt-in RenderDoc
diagnostic, which still expects files no setup script creates.
Adds 7 tests to tests/test_setup_portability.py.
Signed-off-by: zero <zero@localhost>
zero