[clang-tidy] cpp: Turn reference operators to const

Found with cppcoreguidelines-c-copy-assignment-signature

Signed-off-by: Rosen Penev <rosenp@gmail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/plist/String.h b/include/plist/String.h
index 80290b3..9aba16b 100644
--- a/include/plist/String.h
+++ b/include/plist/String.h
@@ -34,7 +34,7 @@ public :
     String(Node* parent = NULL);
     String(plist_t node, Node* parent = NULL);
     String(const String& s);
-    String& operator=(String& s);
+    String& operator=(const String& s);
     String(const std::string& s);
     virtual ~String();