fix: guard against pop in iter for range

tests/parser/syntax/test_for_range.py

@@ -57,3 +57,30 @@ def kick_foos():
 @pytest.mark.parametrize("good_code", valid_list)
 def test_range_success(good_code):
     assert compiler.compile_code(good_code) is not None
+
+
+fail_list = [
+    # Cannot call `pop()` in for range because it modifies state
+    (
+        """
+arr: DynArray[uint256, 10]
+
+@external
+def test()-> (DynArray[uint256, 6], DynArray[uint256, 10]):
+    b: DynArray[uint256, 6] = []
+
+    self.arr = [1,0]
+
+    for i in range(self.arr.pop(), self.arr.pop() + 2):
+        b.append(i)
+
+    return b, self.arr
+    """,
+        ImmutableViolation,
+    )
+]
+
+
+@pytest.mark.parametrize("bad_code,exc", fail_list)
+def test_range_fail(assert_compile_failed, get_contract_with_gas_estimation, bad_code, exc):
+    assert_compile_failed(lambda: get_contract_with_gas_estimation(bad_code), exc)

vyper/semantics/analysis/local.py

@@ -343,6 +343,15 @@ def visit_For(self, node):
                 )
             validate_call_args(node.iter, (1, 2))
 
+            # Check if pop` operation is used in `range`
+            darray_pop_nodes = node.iter.get_descendants(vy_ast.Attribute, {"attr": "pop"})
+            if len(darray_pop_nodes) > 0:
+                pop_node = darray_pop_nodes.pop()
+                raise ImmutableViolation(
+                    "Cannot call `pop` inside for loop because it modifies the dynamic array",
+                    pop_node,
+                )
+
             args = node.iter.args
             if len(args) == 1:
                 # range(CONSTANT)