Merge pull request #6827 from trexfeathers/dataset_iterable

Compatibility with NetCDF4 v1.7.3 and unpin Dask

Author: stephenworsley

docs/src/whatsnew/3.14.rst

@@ -63,6 +63,11 @@ v3.14.1 (Date TBD)
    #. Tentative compatibility with Python 3.14, pending full CI support later.
       :ref:`See Dependencies for more<3_14_dependencies>`.
 
+   #. Removed netCDF4<1.7.3 temporary pin.
+
+   #. Enabled Dask versions beyond `2025.10` (`2025.10.0` contained a known bug
+      and is therefore disabled).
+
 ✨ Features
 ===========
 
@@ -180,7 +185,8 @@ v3.14.1 (Date TBD)
 
 #. `@pp-mo`_ added a temporary dependency pins for Python<3.14, dask<2025.10.0 and
    netCDF4<1.7.3.  Edit 2025-12-03: the Python pin has now been removed in
-   :pull:`6817`.
+   :pull:`6817`, :pull:`6826` has removed the netCDF4 pin and
+   replaced the Dask pin with a negation (``!=2025.10.0``).
    (:issue:`6775`, :issue:`6776`, :issue:`6777`, :pull:`6773`)
 
 #. `@trexfeathers`_ provided tentative compatibility with Python 3.14 by fixing
@@ -189,6 +195,14 @@ v3.14.1 (Date TBD)
    dependencies, but the relevant tests have been shown to pass in :pull:`6816`.
    (:issue:`6775`, :pull:`6817`)
 
+#. `@trexfeathers`_ fixed an incompatibility with the netCDF4 package (relating
+   to dataset iterability). (:issue:`6777`, :pull:`6826`)
+
+#. `@trexfeathers`_ replaced the Dask version pin with a negation
+   (``!=2025.10.0``), as the relevant bug has been fixed in subsequent Dask
+   releases. (:issue:`6776`, :pull:`6826`)
+
+
 
 📚 Documentation
 ================

lib/iris/loading.py

@@ -69,8 +69,12 @@ def _generate_cubes(uris, callback, constraints):
     import iris.io
 
     """Return a generator of cubes given the URIs and a callback."""
-    if isinstance(uris, str) or not isinstance(uris, Iterable):
-        # Make a string, or other single item, into an iterable.
+    if (
+        isinstance(uris, str)
+        or hasattr(uris, "fromcdl")
+        or not isinstance(uris, Iterable)
+    ):
+        # Make a string, Dataset, or other single item, into an iterable.
         uris = [uris]
 
     # Group collections of uris by their iris handler

requirements/locks/py311-linux-64.lock

@@ -14,10 +14,10 @@ dependencies:
   - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
-  - dask-core >=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
+  - dask-core >=2025.1.0,!=2025.10.0
   - libnetcdf !=4.9.1
   - matplotlib-base >=3.5, !=3.9.1
-  - netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
+  - netcdf4
   - numpy >=1.24, !=1.24.3
   - python-xxhash
   - pyproj
@@ -44,7 +44,7 @@ dependencies:
   - imagehash >=4.0
   - pre-commit
   - psutil
-  - pytest
+  - pytest<9
   - pytest-cov
   - pytest-mock
   - pytest-xdist

requirements/locks/py312-linux-64.lock

@@ -14,10 +14,10 @@ dependencies:
   - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
-  - dask-core >=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
+  - dask-core >=2025.1.0,!=2025.10.0
   - libnetcdf !=4.9.1
   - matplotlib-base >=3.5, !=3.9.1
-  - netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
+  - netcdf4
   - numpy >=1.24, !=1.24.3
   - python-xxhash
   - pyproj
@@ -44,7 +44,7 @@ dependencies:
   - imagehash >=4.0
   - pre-commit
   - psutil
-  - pytest
+  - pytest<9
   - pytest-cov
   - pytest-mock
   - pytest-xdist

requirements/locks/py313-linux-64.lock

@@ -14,10 +14,10 @@ dependencies:
   - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
-  - dask-core >=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
+  - dask-core >=2025.1.0,!=2025.10.0
   - libnetcdf !=4.9.1
   - matplotlib-base >=3.5, !=3.9.1
-  - netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
+  - netcdf4
   - numpy >=1.24, !=1.24.3
   - python-xxhash
   - pyproj
@@ -44,7 +44,7 @@ dependencies:
   - imagehash >=4.0
   - pre-commit
   - psutil
-  - pytest
+  - pytest<9
   - pytest-cov
   - pytest-mock
   - pytest-xdist

requirements/py311.yml

@@ -1,10 +1,10 @@
 cartopy>=0.21
 cf-units>=3.1
 cftime>=1.5.0
-dask[array]>=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
+dask[array]>=2025.1.0,!=2025.10.0
 # libnetcdf!=4.9.1 (not available on PyPI)
 matplotlib>=3.5
-netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
+netcdf4
 numpy>=1.24,!=1.24.3
 pyproj
 scipy