CI: improve pytest parameter readability

Author: mloubout

conftest.py

@@ -287,6 +287,21 @@ def pytest_runtest_makereport(item, call):
             result.outcome = 'passed'
 
 
+def pytest_make_parametrize_id(config, val, argname):
+    """
+    Prevents pytest to make obsucre parameter names (param0, param1, ...)
+    and default to str(val) instead for better log readability.
+    """
+    # First see if it has a name
+    if hasattr(val, '__name__'):
+        return val.__name__
+    # Then try str(val)
+    try:
+        return str(val)
+    except Exception:
+        return None  # Fall back to default behavior
+
+
 # A list of optimization options/pipelines to be used in testing
 # regarding spatial and/or temporal blocking.
 opts_tiling = ['advanced',

devito/finite_differences/derivative.py

@@ -2,7 +2,6 @@
 from collections.abc import Iterable
 from functools import cached_property
 from itertools import chain
-import numbers
 
 import sympy
 
@@ -159,14 +158,12 @@ def _validate_expr(expr):
         """
         if type(expr) is sympy.Derivative:
             raise ValueError("Cannot nest sympy.Derivative with devito.Derivative")
-        elif isinstance(expr, numbers.Number):
-            return sympy.S.Zero
         if not isinstance(expr, Differentiable):
             try:
                 expr = diffify(expr)
             except Exception as e:
                 d = type(expr)
-                raise ValueError(f"`expr` must be a `Differentiable` type object not {d}") from e
+                raise ValueError(f"`expr` must be a `Differentiable` not {d}") from e
         return expr
 
     @staticmethod