Merge 0931867 into fdb4b49

ESadek-MO · web-flow · commit 618d9382d9c5 · 2025-07-08T13:07:31.000Z
diff --git a/lib/iris/coords.py b/lib/iris/coords.py
@@ -573,8 +573,9 @@ def reindent_data_string(text, n_indent):
 
     def __setattr__(self, key, value):
         if getattr(self, "_mesh_timestamps", None) is not None:
-            for timestamp in self._mesh_timestamps:
-                timestamp.update()
+            if key in ("_values_dm", "_values", "_bounds_dm", "points", "bounds"):
+                for timestamp in self._mesh_timestamps:
+                    timestamp.update()
         object.__setattr__(self, key, value)
 
     def __str__(self):
diff --git a/lib/iris/mesh/components.py b/lib/iris/mesh/components.py
@@ -2828,7 +2828,23 @@ def __getattribute__(self, item):
         # by calling the method on the base class `object`
         updating = object.__getattribute__(self, "_updating")
         if updating is False and item != "update_from_mesh":
-            object.__getattribute__(self, "update_from_mesh")()
+            # Don't update the points/bounds if you're only getting metadata
+            if item not in (
+                "_metadata_manager_temp",
+                "_metadata_manager",
+                "standard_name",
+                "long_name",
+                "var_name",
+                "units",
+                "attributes",
+                "climatological",
+                "coord_system",
+                "attributes",
+                "haz_lazy_data",
+            ):
+                object.__getattribute__(self, "update_from_mesh")(True)
+            else:
+                object.__getattribute__(self, "update_from_mesh")(False)
         return super().__getattribute__(item)
 
         # Define accessors for MeshCoord-specific properties mesh/location/axis.
@@ -2973,9 +2989,8 @@ def bounds(self, value):
 
     @property
     def _metadata_manager(self):
-        # sets the metadata
+        # update metadata
         use_metadict = self._load_metadata()
-
         self._metadata_manager_temp.standard_name = use_metadict["standard_name"]
         self._metadata_manager_temp.long_name = use_metadict["long_name"]
         self._metadata_manager_temp.var_name = use_metadict["var_name"]
@@ -2998,15 +3013,17 @@ def __getitem__(self, keys):
         # Translate "self[:,]" as "self.copy()".
         return self.copy()
 
-    def update_from_mesh(self):
+    def update_from_mesh(self, points_and_bounds=True):
         try:
             object.__setattr__(self, "_updating", True)
             if (self._last_modified is None) or (
                 self._last_modified < self.mesh._last_modified
             ):
-                points, bounds = self._load_points_and_bounds()
-                super(MeshCoord, self.__class__).points.fset(self, points)
-                super(MeshCoord, self.__class__).bounds.fset(self, bounds)
+                if points_and_bounds:
+                    # update points and bounds
+                    points, bounds = self._load_points_and_bounds()
+                    super(MeshCoord, self.__class__).points.fset(self, points)
+                    super(MeshCoord, self.__class__).bounds.fset(self, bounds)
                 object.__setattr__(self, "_last_modified", self.mesh._last_modified)
         # Ensure errors aren't bypassed
         except Exception as e:
