Enforce usage of typed symbols for reductions

src/pystencils/backend/kernelcreation/freeze.py

@@ -176,6 +176,8 @@ class FreezeExpressions:
         return PsAssignment(lhs, binop_str_to_expr(expr.op[0], lhs.clone(), rhs))
 
     def map_ReducedAssignment(self, expr: ReducedAssignment):
+        assert isinstance(expr.lhs, TypedSymbol)
+
         lhs = self.visit(expr.lhs)
         rhs = self.visit(expr.rhs)
 
@@ -183,7 +185,7 @@ class FreezeExpressions:
         assert isinstance(lhs, PsSymbolExpr)
 
         orig_lhs_symb = lhs.symbol
-        dtype = rhs.dtype  # TODO: kernel with (implicit) up/downcasts?
+        dtype = lhs.dtype
 
         assert isinstance(dtype, PsNumericType)
 

tests/kernelcreation/test_reduction.py

@@ -24,7 +24,7 @@ def test_reduction(dtype, op):
     gpu_avail = False
 
     x = ps.fields(f'x: {dtype}[1d]')
-    w = sp.Symbol("w")
+    w = ps.TypedSymbol("w", dtype)
 
     # kernel with reduction assignment