api: silence non-Expr warning for tensor (e.g staggering/name/..)

Author: mloubout

devito/types/basic.py

@@ -1,5 +1,6 @@
 import abc
 import inspect
+import warnings
 from contextlib import suppress
 from ctypes import POINTER, Structure, _Pointer, c_char, c_char_p
 from functools import cached_property, reduce
@@ -9,6 +10,7 @@
 import sympy
 from sympy.core.assumptions import _assume_rules
 from sympy.core.decorators import call_highest_priority
+from sympy.utilities.exceptions import SymPyDeprecationWarning
 
 from devito.data import default_allocator
 from devito.parameters import configuration
@@ -1533,10 +1535,20 @@ def _sympify(self, arg):
         # This is used internally by sympy to process arguments at rebuilt. And since
         # some of our properties are non-sympyfiable we need to have a fallback
         try:
-            return super()._sympify(arg)
-        except sympy.SympifyError:
+            # Pure sympy object
+            return arg._sympy_()
+        except AttributeError:
             return arg
 
+    @classmethod
+    def _eval_from_dok(cls, rows, cols, dok):
+        with warnings.catch_warnings():
+            warnings.filterwarnings(
+                "ignore",
+                category=SymPyDeprecationWarning
+            )
+            return super()._eval_from_dok(rows, cols, dok)
+
     @property
     def grid(self):
         """

devito/types/utils.py

@@ -59,7 +59,9 @@ def on_node(self):
 
     @property
     def _ref(self):
-        if self.on_node:
+        if not self:
+            return None
+        elif self.on_node:
             return NODE
         else:
             return tuple(d for d, s in zip(self.getters, self, strict=True) if s == 1)