add is_super method

aesara/sparse/type.py

@@ -215,6 +215,17 @@ def value_zeros(self, shape):
 
         return matrix_constructor(shape, dtype=self.dtype)
 
+    def is_super(self, otype):
+        if (
+            isinstance(otype, type(self))
+            and otype.dtype == self.dtype
+            and otype.ndim == self.ndim
+            and self.format == otype.format
+        ):
+            return True
+
+        return False
+
 
 # Register SparseType's C code for ViewOp.
 aesara.compile.register_view_op_c_code(

aesara/tensor/type.py

@@ -315,7 +315,9 @@ def is_super(self, otype):
         return False
 
     def convert_variable(self, var):
-        if self.is_super(var.type):
+        if self.is_super(var.type) and not isinstance(
+            var.type, aesara.sparse.SparseType
+        ):
             # `var.type` is at least as specific as `self`, so we return
             # `var` as-is
             return var