Escape special chars like "&"

Signed-off-by: Knut Ahlers <knut@ahlers.me>

.config/i3blocks/block.py

@@ -1,3 +1,4 @@
+import html
 import os
 
 BTN_LEFT = 1
@@ -77,6 +78,9 @@ class Block:
             text=text,
         ))
 
+    def safe_text(self, text):
+        return html.escape(text)
+
     def set_icon(self, icon):
         """
         Overwrites the icon speicfied in constructor

.config/i3blocks/spotify

@@ -50,10 +50,10 @@ class Spotify(Block):
             'Metadata',
         )
 
-        return "{} - {}".format(
+        return self.safe_text("{} - {}".format(
             meta.get('xesam:artist')[0],
             meta.get('xesam:title'),
-        )
+        ))
 
 
 def main():