add tests for iterators imported from modules

tests/functional/codegen/features/iteration/test_for_in_list.py

@@ -3,6 +3,7 @@
 
 import pytest
 
+from vyper.compiler import compile_code
 from vyper.exceptions import (
     ArgumentException,
     ImmutableViolation,
@@ -841,6 +842,59 @@ def foo():
 ]
 
 
+# TODO: move these to tests/functional/syntax
 @pytest.mark.parametrize("code,err", BAD_CODE, ids=bad_code_names)
 def test_bad_code(assert_compile_failed, get_contract, code, err):
-    assert_compile_failed(lambda: get_contract(code), err)
+    with pytest.raises(err):
+        compile_code(code)
+
+
+def test_iterator_modification_module_attribute(make_input_bundle):
+    # test modifying iterator via attribute
+    lib1 = """
+queue: DynArray[uint256, 5]
+    """
+    main = """
+import lib1
+
+initializes: lib1
+
+@external
+def foo():
+    for i: uint256 in lib1.queue:
+        lib1.queue.pop()
+    """
+
+    input_bundle = make_input_bundle({"lib1.vy": lib1})
+
+    with pytest.raises(ImmutableViolation) as e:
+        compile_code(main, input_bundle=input_bundle)
+
+    assert e.value._message == "Cannot modify loop variable `queue`"
+
+
+def test_iterator_modification_module_function_call(make_input_bundle):
+    lib1 = """
+queue: DynArray[uint256, 5]
+
+@internal
+def popqueue():
+    self.queue.pop()
+    """
+    main = """
+import lib1
+
+initializes: lib1
+
+@external
+def foo():
+    for i: uint256 in lib1.queue:
+        lib1.popqueue()
+    """
+
+    input_bundle = make_input_bundle({"lib1.vy": lib1})
+
+    with pytest.raises(ImmutableViolation) as e:
+        compile_code(main, input_bundle=input_bundle)
+
+    assert e.value._message == "Cannot modify loop variable `queue`"

vyper/semantics/analysis/local.py

@@ -431,7 +431,10 @@ def _analyse_list_iter(self, iter_node, target_type):
                 raise StructureException("For loop must have at least 1 iteration", iter_node)
             iter_type = SArrayT(target_type, len_)
         else:
-            iter_type = get_exact_type_from_node(iter_node)
+            try:
+                iter_type = get_exact_type_from_node(iter_node)
+            except (InvalidType, StructureException):
+                raise InvalidType("Not an iterable type", iter_node)
 
         # CMC 2024-02-09 TODO: use validate_expected_type once we have DArrays
         # with generic length.