Test fails with numpy 1.19.0rc*

[t20100]

Weekly CI test fails (see below), it started to fails with pre-release of numpy v1.19.0rc1 (see https://gitlab.esrf.fr/silx/bob/fabio/pipelines/26203) and is still broken with v1.19.0rc2 (see https://gitlab.esrf.fr/silx/bob/fabio/pipelines/26562):

197 ======================================================================
198 FAIL: test_linear (fabio.test.codecs.test_brukerimage.TestBrukerLinear)
199 test for self consistency of random data read/write
200 ----------------------------------------------------------------------
201 Traceback (most recent call last):
202   File "/opt/python/cp36-cp36m/lib/python3.6/site-packages/fabio/test/codecs/test_brukerimage.py", line 155, in test_linear
203     self.assertTrue(error < numpy.finfo(numpy.float32).eps, "Error is %s>1e-7" % error)
204 AssertionError: False is not true : Error is 0.99999654>1e-7
205 ----------------------------------------------------------------------

[vallsv]

It looks like there is also a huge incompatibility between python 3.5 and setuptools.

https://gitlab.esrf.fr/silx/bob/fabio/-/jobs/106973

[t20100]

numpy 1.19.0* no longer supports python 3.5 (https://github.com/numpy/numpy/releases)

[vallsv]

So there is bug in there pipy dependencies? Or that's on our side?

[vallsv]

Iv checked there side, there is the right flags. No Python 3.5 on the metadata.

[t20100]

I fixed the python3.5 in weekly CI by only installing from binary, but the issue reported here remains...

[kif]

So there are 2 issues:

• numpy 1.19 dropped python 3.5 (exit debian9)
• fabio test suite failing with numpy 1.19 for python 3.6

[kif]

I managed to reproduce the bug on python 3.7: still test_brukerimage

[kif]

The error is probably in the writing as the data are empty.

[kif]

The issue is that float32 is not a subtype of float anymore (was a bug)