'Regression test for https://aeon.stsci.edu/ssb/trac/pyfits/ticket/107
Test of `writeto()` with a trivial header containing a single keyword.'

def test_writeto_2(self):

    data = np.zeros((100, 100))
    header = fits.Header()
    header.set('CRPIX1', 1.0)
    fits.writeto(self.temp('array.fits'), data, header=header, overwrite=True, output_verify='silentfix')
    hdul = fits.open(self.temp('array.fits'))
    assert (len(hdul) == 1)
    assert (data == hdul[0].data).all()
    assert ('CRPIX1' in hdul[0].header)
    assert (hdul[0].header['CRPIX1'] == 1.0)
