The tmp directory must be at the same device partition as the hyp3-isce2 code locate in order to make the tests pass

[cirrusasf]

pytest tests/test_merge_tops_bursts.py fails. it creates the following error:

OSError: [Errno 18] Invalid cross-device link: '/tmp/pytest-of-jiangzhu/pytest-3/test_snaphu_unwrap0/merged/filt_topophase.unw' -> 'tmp.unw'

The problem is that the renameFile function in the maskUnwrap (isceobj.TopsProc.runIon import maskUnwrap) can not do cross-device link.

solution:
Before run the test, create tmp directory to be at the same device partition as the hyp3-isce2 codes locate, and point the TMPDIR environment variable to be the tmp.

For example,

mkdir /home/user/tmp
export TMPDIR=/home/user/tmp
pytest tests/test_merge_tops_bursts.py

successfully.