remove warning and raise error when dataset constructor is called wit… (#1539)

* remove warning and raise error when dataset constructor is called with coords dict and not dims

* remove else clause and improve whats new note

Author: Joe Hamman

doc/whats-new.rst

@@ -15,9 +15,16 @@ What's New
 
 .. _whats-new.0.9.7:
 
-v0.9.7 (unreleased)
+v0.10.0 (unreleased)
 -------------------
 
+Breaking changes
+~~~~~~~~~~~~~~~~
+
+- Supplying ``coords`` as a dictionary to the ``DataArray`` constructor without
+  also supplying an explicit ``dims`` argument is no longer supported. This
+  behavior was deprecated in version 0.9 but is now an error (:issue:`727`).
+  By `Joe Hamman <https://github.com/jhamman>`_.
 Backward Incompatible Changes
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

xarray/core/dataarray.py

@@ -47,15 +47,15 @@ def _infer_coords_and_dims(shape, coords, dims):
         if coords is not None and len(coords) == len(shape):
             # try to infer dimensions from coords
             if utils.is_dict_like(coords):
-                warnings.warn('inferring DataArray dimensions from dictionary '
-                              'like ``coords`` has been deprecated. Use an '
-                              'explicit list of ``dims`` instead.',
-                              FutureWarning, stacklevel=3)
-                dims = list(coords.keys())
-            else:
-                for n, (dim, coord) in enumerate(zip(dims, coords)):
-                    coord = as_variable(coord, name=dims[n]).to_index_variable()
-                    dims[n] = coord.name
+                # deprecated in GH993, removed in GH1539
+                raise ValueError('inferring DataArray dimensions from '
+                                 'dictionary like ``coords`` has been '
+                                 'deprecated. Use an explicit list of '
+                                 '``dims`` instead.')
+            for n, (dim, coord) in enumerate(zip(dims, coords)):
+                coord = as_variable(coord,
+                                    name=dims[n]).to_index_variable()
+                dims[n] = coord.name
         dims = tuple(dims)
     else:
         for d in dims:

xarray/tests/test_dataset.py

@@ -274,7 +274,7 @@ class Arbitrary(object):
             self.assertDatasetIdentical(expected, actual)
 
     def test_constructor_deprecated(self):
-        with pytest.warns(FutureWarning):
+        with self.assertRaisesRegexp(ValueError, 'DataArray dimensions'):
             DataArray([1, 2, 3], coords={'x': [0, 1, 2]})
 
     def test_constructor_auto_align(self):
@@ -1294,9 +1294,11 @@ def test_align_nocopy(self):
         assert source_ndarray(x['foo'].data) is not source_ndarray(x2['foo'].data)
 
     def test_align_indexes(self):
-        x = Dataset({'foo': DataArray([1, 2, 3], coords=[('x', [1, 2, 3])])})
+        x = Dataset({'foo': DataArray([1, 2, 3], dims='x',
+                    coords=[('x', [1, 2, 3])])})
         x2, = align(x, indexes={'x': [2, 3, 1]})
-        expected_x2 = Dataset({'foo': DataArray([2, 3, 1], coords={'x': [2, 3, 1]})})
+        expected_x2 = Dataset({'foo': DataArray([2, 3, 1], dims='x',
+                              coords={'x': [2, 3, 1]})})
         self.assertDatasetIdentical(expected_x2, x2)
 
     def test_align_non_unique(self):