Ok, I can work with that.
So I JUST checked out the latest spack, changed to the develop branch, and executed "spack unit-test".
_________________________________________ TestStage.test_get_stage_root_in_spack __________________________________________
self = <spack.test.stage.TestStage object at 0x7f781c15a190>, clear_stage_root = None
def test_get_stage_root_in_spack(self, clear_stage_root):
"""Ensure an instance path is an accessible build stage path."""
base = canonicalize_path(os.path.join('$spack', '.spack-test-stage'))
mkdirp(base)
test_path = tempfile.mkdtemp(dir=base)
try:
with spack.config.override('config:build_stage', test_path):
path = spack.stage.get_stage_root()
> assert 'spack' in path.split(os.path.sep)
E AssertionError: assert 'spack' in ['', 'home', 'rug262', 'development', 'spack-pullreq', '.spack-test-stage', ...]
E + where ['', 'home', 'rug262', 'development', 'spack-pullreq', '.spack-test-stage', ...] = <built-in method split of str object at 0x7f7784569030>('/')
E + where <built-in method split of str object at 0x7f7784569030> = '/home/rug262/development/spack-pullreq/.spack-test-stage/tmpj41gewiw'.split
E + and '/' = <module 'posixpath' from '/usr/lib64/python3.7/posixpath.py'>.sep
E + where <module 'posixpath' from '/usr/lib64/python3.7/posixpath.py'> = os.path
lib/spack/spack/test/stage.py:839: AssertionError
Hrmmm. Using python 3.7.9. on Fedora 31.