Fix Attribute::unescape_value does not unescape predefined entities since tafia#739

Author: Mingun

Changelog.md

@@ -26,6 +26,7 @@
   As a result, the following variants of `quick_xml::escape::EscapeError` are removed:
   - `TooLongDecimal`
   - `TooLongHexadecimal`
+- [#771]: Fixed `Attribute::unescape_value` which does not unescape predefined values since 0.32.0.
 
 ### Misc Changes
 

src/events/attributes.rs

@@ -45,7 +45,7 @@ impl<'a> Attribute<'a> {
     /// [`encoding`]: ../../index.html#encoding
     #[cfg(any(doc, not(feature = "encoding")))]
     pub fn unescape_value(&self) -> XmlResult<Cow<'a, str>> {
-        self.unescape_value_with(|_| None)
+        self.unescape_value_with(resolve_predefined_entity)
     }
 
     /// Decodes using UTF-8 then unescapes the value, using custom entities.