id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
328439361,MDExOlB1bGxSZXF1ZXN0MTkxOTc1NTkz,2207,"Fixes #2198: Drop chunksizes when only when original_shape is different, not when it isn't found",6404167,closed,0,,,4,2018-06-01T09:08:11Z,2019-06-06T20:35:50Z,2019-06-06T20:35:50Z,CONTRIBUTOR,,0,pydata/xarray/pulls/2207,"Before this fix chunksizes was dropped even when
original_shape was not found in encoding

 - [x] Closes #2198
 - [x] Tests added (for all bug fixes or enhancements)
 - [x] Tests passed (for all non-documentation changes)

Four seemingly unrelated tests failed
``` python
___________________________________________________________________________________ TestEncodeCFVariable.test_missing_fillvalue ____________________________________________________________________________________

self = <xarray.tests.test_conventions.TestEncodeCFVariable testMethod=test_missing_fillvalue>

    def test_missing_fillvalue(self):
        v = Variable(['x'], np.array([np.nan, 1, 2, 3]))
        v.encoding = {'dtype': 'int16'}
        with pytest.warns(Warning, match='floating point data as an integer'):
>           conventions.encode_cf_variable(v)
E           Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) was emitted. The list of emitted warnings is: [SerializationWarning('saving variable None with floating point data as an integer dtype without any _FillValue to use for NaNs',)].

xarray/tests/test_conventions.py:89: Failed
----------------------------------------------------------------------------------------------- Captured stderr call -----------------------------------------------------------------------------------------------
/usr/lib/python3.6/site-packages/_pytest/vendored_packages/pluggy.py:248: SerializationWarning: saving variable None with floating point data as an integer dtype without any _FillValue to use for NaNs
  call_outcome = _CallOutcome(func)
____________________________________________________________________________________________ TestAccessor.test_register ____________________________________________________________________________________________

self = <xarray.tests.test_extensions.TestAccessor testMethod=test_register>

    def test_register(self):
    
        @xr.register_dataset_accessor('demo')
        @xr.register_dataarray_accessor('demo')
        class DemoAccessor(object):
            """"""Demo accessor.""""""
    
            def __init__(self, xarray_obj):
                self._obj = xarray_obj
    
            @property
            def foo(self):
                return 'bar'
    
        ds = xr.Dataset()
        assert ds.demo.foo == 'bar'
    
        da = xr.DataArray(0)
        assert da.demo.foo == 'bar'
    
        # accessor is cached
        assert ds.demo is ds.demo
    
        # check descriptor
        assert ds.demo.__doc__ == ""Demo accessor.""
        assert xr.Dataset.demo.__doc__ == ""Demo accessor.""
        assert isinstance(ds.demo, DemoAccessor)
        assert xr.Dataset.demo is DemoAccessor
    
        # ensure we can remove it
        del xr.Dataset.demo
        assert not hasattr(xr.Dataset, 'demo')
    
        with pytest.warns(Warning, match='overriding a preexisting attribute'):
            @xr.register_dataarray_accessor('demo')
>           class Foo(object):
E           Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) was emitted. The list of emitted warnings is: [AccessorRegistrationWarning(""registration of accessor <class 'xarray.tests.test_extensions.TestAccessor.test_register.<locals>.Foo'> under name 'demo' for type <class 'xarray.core.dataarray.DataArray'> is overriding a preexisting attribute with the same name."",)].

xarray/tests/test_extensions.py:60: Failed
----------------------------------------------------------------------------------------------- Captured stderr call -----------------------------------------------------------------------------------------------
/home/karel/working/xarray/xarray/tests/test_extensions.py:60: AccessorRegistrationWarning: registration of accessor <class 'xarray.tests.test_extensions.TestAccessor.test_register.<locals>.Foo'> under name 'demo' for type <class 'xarray.core.dataarray.DataArray'> is overriding a preexisting attribute with the same name.
  class Foo(object):
__________________________________________________________________________________________________ TestAlias.test __________________________________________________________________________________________________

self = <xarray.tests.test_utils.TestAlias testMethod=test>

    def test(self):
        def new_method():
            pass
        old_method = utils.alias(new_method, 'old_method')
        assert 'deprecated' in old_method.__doc__
        with pytest.warns(Warning, match='deprecated'):
>           old_method()
E           Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) was emitted. The list of emitted warnings is: [FutureWarning('old_method has been deprecated. Use new_method instead.',)].

xarray/tests/test_utils.py:28: Failed
----------------------------------------------------------------------------------------------- Captured stderr call -----------------------------------------------------------------------------------------------
/home/karel/working/xarray/xarray/tests/test_utils.py:28: FutureWarning: old_method has been deprecated. Use new_method instead.
  old_method()
_____________________________________________________________________________________ TestIndexVariable.test_coordinate_alias ______________________________________________________________________________________

self = <xarray.tests.test_variable.TestIndexVariable testMethod=test_coordinate_alias>

    def test_coordinate_alias(self):
        with pytest.warns(Warning, match='deprecated'):
>           x = Coordinate('x', [1, 2, 3])
E           Failed: DID NOT WARN. No warnings of type (<class 'Warning'>,) was emitted. The list of emitted warnings is: [FutureWarning('Coordinate has been deprecated. Use IndexVariable instead.',)].

xarray/tests/test_variable.py:1763: Failed
----------------------------------------------------------------------------------------------- Captured stderr call -----------------------------------------------------------------------------------------------
/home/karel/working/xarray/xarray/tests/test_variable.py:1763: FutureWarning: Coordinate has been deprecated. Use IndexVariable instead.
  x = Coordinate('x', [1, 2, 3])
```
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