Revert "Deprecate bool(ds) (#6126)" (#6141)

Author: dcherian

doc/whats-new.rst

@@ -40,11 +40,6 @@ Deprecations
   By `Tom Nicholas <https://github.com/TomNicholas>`_.
 
 
-- Coercing a dataset to bool, e.g. ``bool(ds)``, is being deprecated and will raise an
-  error in a future version (not yet planned). For now, invoking ``Dataset.__bool__``
-  issues a ``PendingDeprecationWarning`` (:issue:`6124`, :pull:`6126`).
-  By `Michael Delgado <https://github.com/delgadom>`_.
-
 Bug fixes
 ~~~~~~~~~
 - Properly support :py:meth:`DataArray.ffill`, :py:meth:`DataArray.bfill`, :py:meth:`Dataset.ffill` and :py:meth:`Dataset.bfill` along chunked dimensions (:issue:`6112`).

xarray/core/dataset.py

@@ -1456,14 +1456,6 @@ def __len__(self) -> int:
         return len(self.data_vars)
 
     def __bool__(self) -> bool:
-        warnings.warn(
-            "coercing a Dataset to a bool will be deprecated. "
-            "Using bool(ds.data_vars) to check for at least one "
-            "data variable or using Dataset.to_array to test "
-            "whether array values are true is encouraged.",
-            PendingDeprecationWarning,
-            stacklevel=2,
-        )
         return bool(self.data_vars)
 
     def __iter__(self) -> Iterator[Hashable]:

xarray/tests/test_dataset.py

@@ -544,9 +544,7 @@ def test_properties(self):
         assert "aasldfjalskdfj" not in ds.variables
         assert "dim1" in repr(ds.variables)
         assert len(ds) == 3
-
-        with pytest.warns(PendingDeprecationWarning):
-            assert bool(ds)
+        assert bool(ds)
 
         assert list(ds.data_vars) == ["var1", "var2", "var3"]
         assert list(ds.data_vars.keys()) == ["var1", "var2", "var3"]