fix: guard against kwargs for range expressions with two arguments (v…

…yperlang#3551)

and slight refactor -- extract `node.iter` expr to `range_` for clarity

---------

Co-authored-by: Charles Cooper <cooper.charles.m@gmail.com>

tests/parser/syntax/test_for_range.py

@@ -12,7 +12,26 @@ def foo():
         pass
     """,
         StructureException,
-    )
+    ),
+    (
+        """
+@external
+def bar():
+    for i in range(1,2,bound=2):
+        pass
+    """,
+        StructureException,
+    ),
+    (
+        """
+@external
+def bar():
+    x:uint256 = 1
+    for i in range(x,x+1,bound=2):
+        pass
+    """,
+        StructureException,
+    ),
 ]
 
 

vyper/semantics/analysis/local.py

@@ -346,10 +346,11 @@ def visit_For(self, node):
                 raise IteratorException(
                     "Cannot iterate over the result of a function call", node.iter
                 )
-            validate_call_args(node.iter, (1, 2), kwargs=["bound"])
+            range_ = node.iter
+            validate_call_args(range_, (1, 2), kwargs=["bound"])
 
-            args = node.iter.args
-            kwargs = {s.arg: s.value for s in node.iter.keywords or []}
+            args = range_.args
+            kwargs = {s.arg: s.value for s in range_.keywords or []}
             if len(args) == 1:
                 # range(CONSTANT)
                 n = args[0]
@@ -371,6 +372,13 @@ def visit_For(self, node):
                     type_list = get_common_types(n, bound)
 
             else:
+                if range_.keywords:
+                    raise StructureException(
+                        "Keyword arguments are not supported for `range(N, M)` and"
+                        "`range(x, x + N)` expressions",
+                        range_.keywords[0],
+                    )
+
                 validate_expected_type(args[0], IntegerT.any())
                 type_list = get_common_types(*args)
                 if not isinstance(args[0], vy_ast.Constant):