Make Iris backwards compatible with Cartopy

docs/src/whatsnew/latest.rst

@@ -78,9 +78,7 @@ This document explains the changes made to Iris for this release
 🔗 Dependencies
 ===============
 
-#. `@trexfeathers`_ introduced a ``!=0.23`` Cartopy pin, to avoid
-   a previous bug of titles clashing with axis labels.
-   (`cartopy#2390`_, :pull:`6171`)
+#. N/A
 
 
 📚 Documentation
@@ -95,6 +93,9 @@ This document explains the changes made to Iris for this release
    in Iris v3.10.0, :pull:`5948`) to use the same statistical repeat strategy
    as timing benchmarks. (:pull:`5981`)
 
+#. `@trexfeathers`_ adapted Iris to work with Cartopy v0.24. (:pull:`6171`,
+   :pull:`6172`)
+
 
 .. comment
     Whatsnew author names (@github name) in alphabetical order. Note that,

lib/iris/plot.py

@@ -12,6 +12,7 @@
 import datetime
 import warnings
 
+import cartopy
 import cartopy.crs as ccrs
 from cartopy.geodesic import Geodesic
 import cartopy.mpl.geoaxes
@@ -25,6 +26,7 @@
 import matplotlib.transforms as mpl_transforms
 import numpy as np
 import numpy.ma as ma
+from packaging.version import Version
 
 import iris.analysis.cartography as cartography
 import iris.coord_systems
@@ -43,6 +45,26 @@
 PlotDefn = collections.namedtuple("PlotDefn", ("coords", "transpose"))
 
 
+class _GeoAxesPatched(cartopy.mpl.geoaxes.GeoAxes):
+    # Workaround for a bug where titles collide with axis labels (cartopy#2390)
+    # Bug is only present in Cartopy v0.23, so this will only be invoked for
+    #  that version.
+    def _draw_preprocess(self, renderer):
+        super()._draw_preprocess(renderer)
+
+        for artist in self.artists:
+            if hasattr(artist, "_draw_gridliner"):
+                # Note this is only necessary since Cartopy v0.23, but is not
+                #  wasteful for earlier versions as _draw_gridliner() includes
+                #  a check for whether a draw is necessary.
+                artist._draw_gridliner(renderer=renderer)
+
+
+cartopy_version = Version(cartopy.__version__)
+if cartopy_version.major == 0 and cartopy_version.minor == 23:
+    cartopy.mpl.geoaxes.GeoAxes = _GeoAxesPatched
+
+
 def _get_plot_defn_custom_coords_picked(cube, coords, mode, ndims=2):
     def names(coords):
         result = []

requirements/py310.yml

@@ -11,7 +11,7 @@ dependencies:
   - setuptools-scm >=7
 
 # Core dependencies.
-  - cartopy >=0.21,!=0.23
+  - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
   - dask-core >=2022.9.0,!=2024.8.0

requirements/py311.yml

@@ -11,7 +11,7 @@ dependencies:
   - setuptools-scm >=7
 
 # Core dependencies.
-  - cartopy >=0.21,!=0.23
+  - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
   - dask-core >=2022.9.0,!=2024.8.0

requirements/py312.yml

@@ -11,7 +11,7 @@ dependencies:
   - setuptools-scm >=7
 
 # Core dependencies.
-  - cartopy >=0.21,!=0.23
+  - cartopy >=0.21
   - cf-units >=3.1
   - cftime >=1.5
   - dask-core >=2022.9.0,!=2024.8.0

requirements/pypi-core.txt

@@ -1,4 +1,4 @@
-cartopy>=0.21,!=0.23
+cartopy>=0.21
 cf-units>=3.1
 cftime>=1.5.0
 dask[array]>=2022.9.0,!=2024.8.0