Treat correctly variable deprecations

Author: vkarak

reframe/core/variables.py

@@ -246,10 +246,12 @@ def create_deprecated(cls, var, message,
         ret._target = var._target
         return ret
 
-    def _check_deprecation(self, kind):
-        if isinstance(self.field, fields.DeprecatedField):
-            if self.field.op & kind:
-                user_deprecation_warning(self.field.message)
+    def _warn_deprecation(self, kind):
+        if self.is_deprecated() and self.field.op & kind:
+            user_deprecation_warning(self.field.message)
+
+    def is_deprecated(self):
+        return isinstance(self._p_field, fields.DeprecatedField)
 
     def is_loggable(self):
         return self._loggable
@@ -261,7 +263,7 @@ def undefine(self):
         self._default_value = Undefined
 
     def define(self, value):
-        self._check_deprecation(DEPRECATE_WR)
+        self._warn_deprecation(DEPRECATE_WR)
         self._default_value = value
 
     @property
@@ -283,11 +285,14 @@ def default_value(self):
         # Variables must be returned by-value to prevent an instance from
         # modifying the class variable space.
         self._check_is_defined()
-        self._check_deprecation(DEPRECATE_RD)
+        self._warn_deprecation(DEPRECATE_RD)
         return copy.deepcopy(self._default_value)
 
     @property
     def _field(self):
+        if self.is_deprecated():
+            return self._p_field
+
         if self._target:
             return self._target._field
         else:
@@ -677,7 +682,7 @@ def __init__(self, other):
         for name in self.__slots__:
             setattr(self, name, getattr(other, name))
 
-        self._check_deprecation(DEPRECATE_RD)
+        self._warn_deprecation(DEPRECATE_RD)
 
 
 class VarSpace(namespaces.Namespace):

unittests/test_variables.py

@@ -9,6 +9,7 @@
 
 import reframe as rfm
 from reframe.core.exceptions import ReframeSyntaxError
+from reframe.core.warnings import ReframeDeprecationWarning
 
 
 @pytest.fixture
@@ -458,7 +459,6 @@ class A(rfm.RegressionTest):
 
 def test_var_deprecation():
     from reframe.core.variables import DEPRECATE_RD, DEPRECATE_WR
-    from reframe.core.warnings import ReframeDeprecationWarning
 
     # Check read deprecation
     class A(rfm.RegressionMixin):
@@ -544,3 +544,15 @@ class S(T):
 
     s.x = 3
     assert s.y == 3
+
+    # Test deprecated aliases
+    class S(T):
+        y = deprecate(variable(alias=x), f'y is deprecated')
+
+    with pytest.warns(ReframeDeprecationWarning):
+        class U(S):
+            y = 10
+
+    s = S()
+    with pytest.warns(ReframeDeprecationWarning):
+        s.y = 10