extend typification tests to check type of each expression

tests/nbackend/kernelcreation/test_typification.py

@@ -38,6 +38,7 @@ def test_typify_simple():
     assert isinstance(fasm, PsDeclaration)
 
     def check(expr):
+        assert expr.dtype == ctx.default_dtype
         match expr:
             case PsConstantExpr(cs):
                 assert cs.value == 2
@@ -86,6 +87,7 @@ def test_contextual_typing():
     expr = typify(expr)
 
     def check(expr):
+        assert expr.dtype == ctx.default_dtype
         match expr:
             case PsConstantExpr(cs):
                 assert cs.value in (2, 3, -4)