From 67ea7c8ee19cd97517b1aab1e7a939ebfa3d5aa8 Mon Sep 17 00:00:00 2001
From: Sergei Trofimov <sergei.trofimov@arm.com>
Date: Thu, 22 Mar 2018 12:11:28 +0000
Subject: [PATCH] utils/types: toggle_set: TypeError on string

Strings are iterable, so can be used to instantiate sets (resulting in a
set of chars). This is never what we want for toggle_set's though, and
may result in difficult-to-interpret errors when parsing configuration,
so raise a TypeError if attempting to create a toggle_set with a string.
---
 wa/utils/types.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/wa/utils/types.py b/wa/utils/types.py
index 8ede60da..607c5a84 100644
--- a/wa/utils/types.py
+++ b/wa/utils/types.py
@@ -381,6 +381,14 @@ class toggle_set(set):
                 dest.add(item)
         return dest
 
+    def __init__(self, *args):
+        if args:
+            value = args[0]
+            if isinstance(value, basestring):
+                msg = 'invalid type for toggle_set: "{}"'
+                raise TypeError(msg.format(type(value)))
+        set.__init__(self, *args)
+
     def merge_with(self, other):
         new_self = copy(self)
         return toggle_set.merge(other, new_self)