Undeprecate dict argument for coords in DataArray (#5527)

doc/whats-new.rst

@@ -21,7 +21,9 @@ v0.18.3 (unreleased)
 
 New Features
 ~~~~~~~~~~~~
-
+- Allow passing a dictionary as coords to a :py:class:`DataArray` (:issue:`5527`,
+  reverts :pull:`1539`, which had deprecated this due to python's inconsistent ordering in earlier versions).
+  By `Sander van Rijn <https://github.com/sjvrijn>`_.
 - Added :py:meth:`Dataset.coarsen.construct`, :py:meth:`DataArray.coarsen.construct` (:issue:`5454`, :pull:`5475`).
   By `Deepak Cherian <https://github.com/dcherian>`_.
 - Xarray now uses consolidated metadata by default when writing and reading Zarr

xarray/core/dataarray.py

@@ -117,16 +117,11 @@ def _infer_coords_and_dims(
         if coords is not None and len(coords) == len(shape):
             # try to infer dimensions from coords
             if utils.is_dict_like(coords):
-                # deprecated in GH993, removed in GH1539
-                raise ValueError(
-                    "inferring DataArray dimensions from "
-                    "dictionary like ``coords`` is no longer "
-                    "supported. 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 = 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
         dims = tuple(dims)
     elif len(dims) != len(shape):
         raise ValueError(
@@ -281,7 +276,8 @@ class DataArray(AbstractArray, DataWithCoords, DataArrayArithmetic):
         Name(s) of the data dimension(s). Must be either a hashable
         (only for 1D data) or a sequence of hashables with length equal
         to the number of dimensions. If this argument is omitted,
-        dimension names default to ``['dim_0', ... 'dim_n']``.
+        dimension names are taken from ``coords`` (if possible) and
+        otherwise default to ``['dim_0', ... 'dim_n']``.
     name : str or None, optional
         Name of this array.
     attrs : dict_like or None, optional

xarray/tests/test_dataarray.py

@@ -304,6 +304,9 @@ def test_constructor(self):
         actual = DataArray(data, coords, ["x", "y"])
         assert_identical(expected, actual)
 
+        actual = DataArray(data, coords)
+        assert_identical(expected, actual)
+
         coords = [("x", ["a", "b"]), ("y", [-1, -2, -3])]
         actual = DataArray(data, coords)
         assert_identical(expected, actual)
@@ -332,6 +335,10 @@ def test_constructor(self):
         expected = Dataset({None: (["x", "y"], data, {}, {"bar": 2})})[None]
         assert_identical(expected, actual)
 
+        actual = DataArray([1, 2, 3], coords={"x": [0, 1, 2]})
+        expected = DataArray([1, 2, 3], coords=[("x", [0, 1, 2])])
+        assert_identical(expected, actual)
+
     def test_constructor_invalid(self):
         data = np.random.randn(3, 2)
 

xarray/tests/test_dataset.py

@@ -419,10 +419,6 @@ class Arbitrary:
             actual = Dataset({"x": arg})
             assert_identical(expected, actual)
 
-    def test_constructor_deprecated(self):
-        with pytest.raises(ValueError, match=r"DataArray dimensions"):
-            DataArray([1, 2, 3], coords={"x": [0, 1, 2]})
-
     def test_constructor_auto_align(self):
         a = DataArray([1, 2], [("x", [0, 1])])
         b = DataArray([3, 4], [("x", [1, 2])])