support backwards compatibility

Author: mrocklin

xarray/core/dataarray.py

@@ -646,9 +646,8 @@ def compute(self, **kwargs):
         --------
         dask.array.compute
         """
-        import dask
-        (result,) = dask.compute(self, **kwargs)
-        return result
+        new = self.copy(deep=False)
+        return new.load(**kwargs)
 
     def persist(self, **kwargs):
         """ Trigger computation in constituent dask arrays
@@ -666,9 +665,8 @@ def persist(self, **kwargs):
         --------
         dask.persist
         """
-        import dask
-        (result,) = dask.persist(self, **kwargs)
-        return result
+        ds = self._to_temp_dataset().persist(**kwargs)
+        return self._from_temp_dataset(ds)
 
     def copy(self, deep=True):
         """Returns a copy of this array.

xarray/core/dataset.py

@@ -618,9 +618,8 @@ def persist(self, **kwargs):
         --------
         dask.persist
         """
-        import dask
-        (result,) = dask.persist(self, **kwargs)
-        return result
+        new = self.copy(deep=False)
+        return new._persist_inplace(**kwargs)
 
     @classmethod
     def _construct_direct(cls, variables, coord_names, dims=None, attrs=None,

xarray/core/variable.py

@@ -360,9 +360,8 @@ def compute(self, **kwargs):
         --------
         dask.array.compute
         """
-        import dask
-        (result,) = dask.compute(self, **kwargs)
-        return result
+        new = self.copy(deep=False)
+        return new.load(**kwargs)
 
     def __dask_graph__(self):
         if isinstance(self._data, dask_array_type):

xarray/tests/test_dask.py

@@ -206,6 +206,8 @@ def test_bivariate_ufunc(self):
         self.assertLazyAndAllClose(np.maximum(u, 0), xu.maximum(v, 0))
         self.assertLazyAndAllClose(np.maximum(u, 0), xu.maximum(0, v))
 
+    @pytest.mark.skipif(LooseVersion(dask.__version__) < '0.16',
+                        reason='Need dask 0.16+ for new interface')
     def test_compute(self):
         u = self.eager_var
         v = self.lazy_var
@@ -216,6 +218,8 @@ def test_compute(self):
 
         assert ((u + 1).data == v2.data).all()
 
+    @pytest.mark.skipif(LooseVersion(dask.__version__) < '0.16',
+                        reason='Need dask 0.16+ for new interface')
     def test_persist(self):
         u = self.eager_var
         v = self.lazy_var + 1
@@ -275,6 +279,8 @@ def test_lazy_array(self):
         actual = xr.concat([v[:2], v[2:]], 'x')
         self.assertLazyAndAllClose(u, actual)
 
+    @pytest.mark.skipif(LooseVersion(dask.__version__) < '0.16',
+                        reason='Need dask 0.16+ for new interface')
     def test_compute(self):
         u = self.eager_array
         v = self.lazy_array
@@ -285,6 +291,8 @@ def test_compute(self):
 
         assert ((u + 1).data == v2.data).all()
 
+    @pytest.mark.skipif(LooseVersion(dask.__version__) < '0.16',
+                        reason='Need dask 0.16+ for new interface')
     def test_persist(self):
         u = self.eager_array
         v = self.lazy_array + 1
@@ -730,6 +738,8 @@ def build_dask_array(name):
         chunks=((1,),), dtype=np.int64)
 
 
+@pytest.mark.skipif(LooseVersion(dask.__version__) < '0.16',
+                    reason='Need dask 0.16+ for new interface')
 @pytest.mark.parametrize('persist', [lambda x: x.persist(),
                                      lambda x: dask.persist(x)[0]])
 def test_persist_Dataset(persist):
@@ -743,8 +753,12 @@ def test_persist_Dataset(persist):
     assert len(ds2.foo.data.dask) == 1
     assert len(ds.foo.data.dask) == n  # doesn't mutate in place
 
-@pytest.mark.parametrize('persist', [lambda x: x.persist(),
-                                     lambda x: dask.persist(x)[0]])
+@pytest.mark.parametrize('persist', [
+    lambda x: x.persist(),
+    pytest.mark.skipif(LooseVersion(dask.__version__) < '0.16',
+                       lambda x: dask.persist(x)[0],
+                       reason='Need Dask 0.16+')
+])
 def test_persist_DataArray(persist):
     x = da.arange(10, chunks=(5,))
     y = DataArray(x)

xarray/tests/test_distributed.py

@@ -36,6 +36,7 @@ def test_dask_distributed_integration_test(loop, engine):
                     assert_allclose(original, computed)
 
 
+@pytest.mark.skipif(distributed.__version__ <= '1.19.3')
 @gen_cluster(client=True, timeout=None)
 def test_async(c, s, a, b):
     x = create_test_data()
@@ -63,5 +64,4 @@ def test_async(c, s, a, b):
     assert not dask.is_dask_collection(w)
     assert_allclose(x + 10, w)
 
-
     assert s.task_state