switch "manual" tempdirs for testing to pytest tmpdir fixtures

[Stefan Appelhoff]

Making use of this feature: https://docs.pytest.org/en/stable/tmpdir.html

Replacing this code:

pybv/pybv/tests/test_bv_writer.py

Lines 103 to 113 in 54da125

 @pytest.mark.parametrize("meas_date,match", 
                          [(1, '`meas_date` must be of type str, datetime'), 
                           ('', 'Got a str for `meas_date`, but it was'), 
                           ('1973', 'Got a str for `meas_date`, but it was')]) 
 def test_bad_meas_date(meas_date, match): 
     """Test that bad measurement dates raise errors.""" 
     tmpdir = _mktmpdir() 
     with pytest.raises(ValueError, match=match): 
         write_brainvision(data, sfreq, ch_names, fname, tmpdir, 
                           meas_date=meas_date) 
     rmtree(tmpdir) 

... with the following:

 @pytest.mark.parametrize("meas_date,match", 
                          [(1, '`meas_date` must be of type str, datetime'), 
                           ('', 'Got a str for `meas_date`, but it was'), 
                           ('1973', 'Got a str for `meas_date`, but it was')]) 
+ def test_bad_meas_date(tmpdir, meas_date, match): 
     """Test that bad measurement dates raise errors.""" 
-     tmpdir = _mktmpdir() 
     with pytest.raises(ValueError, match=match): 
         write_brainvision(data, sfreq, ch_names, fname, tmpdir, 
                           meas_date=meas_date) 
-     rmtree(tmpdir) 

This would clean up the code by a bit and follow best practice for pytest.