Avoid double-quotes in field error messages JS code

tailbone/forms/core.py

@@ -904,10 +904,19 @@ class Form(object):
             # show errors if present
             error_messages = self.get_error_messages(field)
             if error_messages:
+
+                # TODO: this surely can't be what we ought to do
+                # here..?  seems like we must pass JS but not JSON,
+                # sort of, so we custom-write the JS code to ensure
+                # single instead of double quotes delimit strings
+                # within the code.
+                message = '[{}]'.format(', '.join([
+                    "'{}'".format(msg.replace("'", r"\'"))
+                    for msg in error_messages]))
+
                 attrs.update({
                     'type': 'is-danger',
-                    # ':message': self.messages_json(error_messages),
-                    ':message': error_messages,
+                    ':message': message,
                 })
 
             # merge anything caller provided