diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
index c035558..20bdb91 100644
--- a/src/testdir/test_vim9_assign.vim
+++ b/src/testdir/test_vim9_assign.vim
@@ -350,7 +350,7 @@
     var lines: list<string>
     lines['a'] = 'asdf'
   END
-  CheckDefFailure(lines, 'E39:', 2)
+  CheckDefFailure(lines, 'E1012:', 2)
 
   lines =<< trim END
     var lines: string
@@ -561,6 +561,15 @@
   CheckDefExecFailure(lines, 'E1147:', 2)
 enddef
 
+def Test_assignment_list_any_index()
+   var l: list<number> = [1, 2]
+  for  [x, y, _]
+  in  [[0, 1, ''], [1, 3, '']]
+      l[x] = l[x] + y
+  endfor
+  assert_equal([2, 5], l)
+enddef
+
 def Test_assignment_list_vim9script()
   var lines =<< trim END
     vim9script
@@ -1405,7 +1414,7 @@
   CheckDefExecFailure([
     'var ll = [1]',
     'unlet ll[g:astring]',
-    ], 'E39:', 2)
+    ], 'E1012:', 2)
   CheckDefExecFailure([
     'var dd = test_null_dict()',
     'unlet dd["a"]',