XMLParser les revendications Pharo U + 00A0 est "UTF-8 non valide"

Question

Compte tenu de l'entrée: ""

<?xml version='1.0' encoding='UTF-8' standalone='yes' ?> 
<sms body=". what" /> 

Lorsque le caractère après le dans l'attribut body de l'étiquette de sms est U+00A0;

Je reçois l'erreur:

XMLEncodingException: Invalid UTF-8 character encoding (line 2) (column 13)

IIUC, la représentation UTF-8 de ce caractère est 0xC2 0xA0per Wikipedia. Effectivement, les octets 72 et 73 de l'entrée sont respectivement 194 et 160.

Cela ressemble à un bug dans XMLParser, ou est-ce que quelque chose me manque?

Answer 1

Merci à Monty pour venir à la rescousse on the Pharo User's list:

You're double decoding. Use onFileNamed:/parseFileNamed: instead (and the DOM printToFileNamed: family of messages when writing) and let XMLParser take care this for you, or disable XMLParser decoding before parsing with #decodesCharacters:.

Longer explanation:

The class #on:/#parse: take either a string or a stream (read the definitions). You gave it a FileReference, but because the argument is tested with isString and sent #readStream otherwise, it didn't blowup then.

File refs sent #readStream return file streams that do automatic decoding. But XMLParser automatically attempts its own decoding too, if:

The input starts with a BOM or it can be inferred by null bytes before or after the first non-null byte.

There is an encoding declaration with a non-UTF-8 encoding.

There is a UTF-8 encoding declaration but the stream is not a normal ReadStream (your case).

So it gets decoded twice, and the decoded value of the char causes the error. I'll consider changing the heuristic to make less eager to decode.