Adopt pins to fix outstanding dependency problems. (#6773)

* Adopt pins to fix outstanding dependency problems, ready for v3.14.0 release.

* Add python<3.14 pin to the pypi dependencies.

* Also pin Python<3.14; add issue refs for all 3 pins; add whatsnew.

* Move the Python pin from pypi-core.txt into pyproject.toml.

Author: pp-mo

docs/src/whatsnew/latest.rst

@@ -129,6 +129,12 @@ This document explains the changes made to Iris for this release
    :func:`iris.util.mask_cube_from_shape`. These packages support new functionality that 
    handles additional shapefile types and projections. (:issue:`6126`, :pull:`6129`)
 
+#. `@pp-mo`_ added a temporary dependency pins for Python<3.14, dask<2025.10.0 and
+   netCDF4<1.7.3.  All of these introduce problems that won't necessarily be fixed soon,
+   so we anticipate that these pins will be wanted for the v3.14 release.
+   (:issue:`6775`, :issue:`6776`, :issue:`6777`, :pull:`6773`)
+
+
 📚 Documentation
 ================
 

pyproject.toml

@@ -50,7 +50,9 @@ keywords = [
 license = "BSD-3-Clause"
 license-files = ["LICENSE"]
 name = "scitools-iris"
-requires-python = ">=3.11"
+# NOTE: currently pinning to avoid Python 3.14
+#  see : https://github.com/SciTools/iris/issues/6775
+requires-python = ">=3.11,<3.14"
 
 [project.urls]
 Code = "https://github.com/SciTools/iris"

requirements/py311.yml

@@ -14,10 +14,10 @@ dependencies:
   - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
-  - dask-core >=2025.1.0  # github.com/SciTools/iris/issues/6264
+  - dask-core >=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
   - libnetcdf !=4.9.1
   - matplotlib-base >=3.5, !=3.9.1
-  - netcdf4
+  - netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
   - numpy >=1.24, !=1.24.3
   - python-xxhash
   - pyproj

requirements/py312.yml

@@ -14,10 +14,10 @@ dependencies:
   - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
-  - dask-core >=2025.1.0  # github.com/SciTools/iris/issues/6264
+  - dask-core >=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
   - libnetcdf !=4.9.1
   - matplotlib-base >=3.5, !=3.9.1
-  - netcdf4
+  - netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
   - numpy >=1.24, !=1.24.3
   - python-xxhash
   - pyproj

requirements/py313.yml

@@ -14,10 +14,10 @@ dependencies:
   - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
-  - dask-core >=2025.1.0  # github.com/SciTools/iris/issues/6264
+  - dask-core >=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
   - libnetcdf !=4.9.1
   - matplotlib-base >=3.5, !=3.9.1
-  - netcdf4
+  - netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
   - numpy >=1.24, !=1.24.3
   - python-xxhash
   - pyproj

requirements/pypi-core.txt

@@ -1,10 +1,10 @@
 cartopy>=0.21
 cf-units>=3.1
 cftime>=1.5.0
-dask[array]>=2025.1.0  # github.com/SciTools/iris/issues/6264
+dask[array]>=2025.1.0,<2025.10.0  # https://github.com/SciTools/iris/issues/6776
 # libnetcdf!=4.9.1 (not available on PyPI)
 matplotlib>=3.5
-netcdf4
+netcdf4<1.7.3  # https://github.com/SciTools/iris/issues/6777
 numpy>=1.24,!=1.24.3
 pyproj
 scipy