Web: Fix crash on trailing ';' in Content-Type

Author: progval

plugins/Web/plugin.py

@@ -186,9 +186,14 @@ def getTitle(self, irc, url, raiseErrors, msg):
 
         encoding = None
         if 'Content-Type' in fd.headers:
-            mime_params = [p.split('=', 1)
+            # using p.partition('=') instead of 'p.split('=', 1)' because,
+            # unlike RFC 7231, RFC 9110 allows an empty parameter list
+            # after ';':
+            # * https://www.rfc-editor.org/rfc/rfc9110.html#name-media-type
+            # * https://www.rfc-editor.org/rfc/rfc9110.html#parameter
+            mime_params = [p.partition('=')
                 for p in fd.headers['Content-Type'].split(';')[1:]]
-            mime_params = {k.strip(): v.strip() for (k, v) in mime_params}
+            mime_params = {k.strip(): v.strip() for (k, sep, v) in mime_params}
             if mime_params.get('charset'):
                 encoding = mime_params['charset']
 

plugins/Web/test.py

@@ -85,6 +85,12 @@ def testtitleReddit(self):
                 'title https://www.reddit.com/r/irc/',
                 'Internet Relay Chat')
 
+        def testTitleMarcinfo(self):
+            # Checks that we don't crash on 'Content-Type: text/html;'
+            self.assertResponse(
+                    'title https://marc.info/?l=openbsd-tech&m=169841790407370&w=2',
+                    "'Removing syscall(2) from libc and kernel' - MARC")
+
         def testTitleSnarfer(self):
             try:
                 conf.supybot.plugins.Web.titleSnarfer.setValue(True)