py-astropy: update to 1.3

[lpsinger (Leo Singer)]

Astropy 1.3 is available: ​http://docs.astropy.org/en/stable/whatsnew/1.3.html

[cdeil (Christoph Deil)]

I did the update to Astropy 1.3 in ​https://github.com/macports/macports-ports/pull/131

However, just now, I realised that it's broken.

Apologies for that!!!

$ python3.5 -c 'import astropy.coordinates'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/coordinates/__init__.py", line 13, in <module>
    from .baseframe import *
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/coordinates/baseframe.py", line 1382, in <module>
    from .earth import EarthLocation
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/coordinates/earth.py", line 17, in <module>
    from .builtin_frames import ITRS, GCRS
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/coordinates/builtin_frames/__init__.py", line 28, in <module>
    from .fk5 import FK5
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/coordinates/builtin_frames/fk5.py", line 10, in <module>
    from .. import earth_orientation as earth
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/coordinates/earth_orientation.py", line 16, in <module>
    from ..time import Time
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/time/__init__.py", line 2, in <module>
    from .formats import *
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/time/formats.py", line 15, in <module>
    from .. import _erfa as erfa
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/_erfa/__init__.py", line 4, in <module>
    from .core import *
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/_erfa/core.py", line 43, in <module>
    from . import _core
ImportError: dlopen(/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/_erfa/_core.cpython-35m-darwin.so, 2): Symbol not found: _eraEceq06
  Referenced from: /opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/_erfa/_core.cpython-35m-darwin.so
  Expected in: flat namespace
 in /opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/astropy/_erfa/_core.cpython-35m-darwin.so

The reason, I think, is that erfa needs to be updated from 1.2.0 to 1.3.0: ​https://github.com/liberfa/erfa/releases/tag/v1.3.0

I now see that py-astropy uses cfitsio, expat, wcslib also from other ports, so possibly those also need to be updated?

build.args-append   --use-system-cfitsio \
                    --use-system-expat \
                    --use-system-wcslib \
                    --use-system-erfa

@robitaille - Can you please comment what should be done to fix Astropy? I could make a PR once it's clear how to fix this.

Isn't there some mechanism to prevent such mistakes for coupled ports? Is the requirement in Astropy on an exact version, or is it a minimal requirement?

If there's no mechanism to really declare the required versions of other ports, then maybe a comment with a link to ​http://astropy.readthedocs.io/en/latest/install.html#external-c-libraries would be helpful?

[cdeil (Christoph Deil)]

This should fix the issue: ​https://github.com/macports/macports-ports/pull/133

[Schamschula (Marius Schamschula)]

Fixed in ​https://github.com/macports/macports-ports/commit/7ebe4d5977ecde56040628e7cb56685d7f8a8f2e