Improve API of Attributes::has_nil and deprecate some methods for namespace resolution

Changelog.md

@@ -21,8 +21,12 @@
 ### Misc Changes
 
 - [#908]: Increase minimal supported `serde` version from 1.0.139 to 1.0.180.
+- [#913]: Deprecate `.prefixes()`, `.resolve()`, `.resolve_attribute()`, and `.resolve_element()`
+  of `NsReader`. Use `.resolver().bindings()` and `.resolver().resolve()` methods instead.
+- [#913]: `Attributes::has_nil` now accepts `NamespaceResolver` instead of `Reader<R>`.
 
 [#908]: https://github.com/tafia/quick-xml/pull/908
+[#913]: https://github.com/tafia/quick-xml/pull/913
 
 
 ## 0.38.4 -- 2025-11-??

src/de/mod.rs

@@ -3469,7 +3469,7 @@ impl<'i, R: BufRead> XmlRead<'i> for IoReader<R> {
     }
 
     fn has_nil_attr(&self, start: &BytesStart) -> bool {
-        start.attributes().has_nil(&self.reader)
+        start.attributes().has_nil(self.reader.resolver())
     }
 }
 
@@ -3537,7 +3537,7 @@ impl<'de> XmlRead<'de> for SliceReader<'de> {
     }
 
     fn has_nil_attr(&self, start: &BytesStart) -> bool {
-        start.attributes().has_nil(&self.reader)
+        start.attributes().has_nil(self.reader.resolver())
     }
 }
 

src/events/attributes.rs

@@ -5,8 +5,7 @@
 use crate::encoding::Decoder;
 use crate::errors::Result as XmlResult;
 use crate::escape::{escape, resolve_predefined_entity, unescape_with};
-use crate::name::{LocalName, Namespace, QName};
-use crate::reader::NsReader;
+use crate::name::{LocalName, Namespace, NamespaceResolver, QName};
 use crate::utils::{is_whitespace, Bytes};
 
 use std::fmt::{self, Debug, Display, Formatter};
@@ -367,7 +366,7 @@ impl<'a> Attributes<'a> {
     ///             e => panic!("Unexpected event {:?}", e),
     ///         };
     ///         assert_eq!(
-    ///             (event.name(), event.attributes().has_nil(&$reader)),
+    ///             (event.name(), event.attributes().has_nil($reader.resolver())),
     ///             (QName($name.as_bytes()), $value),
     ///         );
     ///     };
@@ -377,7 +376,7 @@ impl<'a> Attributes<'a> {
     ///     Event::Start(e) => e,
     ///     e => panic!("Unexpected event {:?}", e),
     /// };
-    /// assert_eq!(root.attributes().has_nil(&reader), false);
+    /// assert_eq!(root.attributes().has_nil(reader.resolver()), false);
     ///
     /// // definitely true
     /// check!(reader, "true",          true);
@@ -394,12 +393,12 @@ impl<'a> Attributes<'a> {
     /// ```
     ///
     /// [`xsi:nil`]: https://www.w3.org/TR/xmlschema-1/#xsi_nil
-    pub fn has_nil<R>(&mut self, reader: &NsReader<R>) -> bool {
+    pub fn has_nil(&mut self, resolver: &NamespaceResolver) -> bool {
         use crate::name::ResolveResult::*;
 
         self.any(|attr| {
             if let Ok(attr) = attr {
-                match reader.resolver().resolve_attribute(attr.key) {
+                match resolver.resolve_attribute(attr.key) {
                     (
                         Bound(Namespace(b"http://www.w3.org/2001/XMLSchema-instance")),
                         LocalName(b"nil"),

src/name.rs

@@ -365,13 +365,11 @@ impl<'a> AsRef<[u8]> for Namespace<'a> {
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
-/// Result of [prefix] resolution which creates by [`NamespaceResolver::resolve`], [`NsReader::resolve_attribute`],
-/// [`NsReader::resolve_element`], [`NsReader::read_resolved_event`] and
+/// Result of [prefix] resolution which creates by [`NamespaceResolver::resolve`],
+/// [`NsReader::read_resolved_event`] and
 /// [`NsReader::read_resolved_event_into`] methods.
 ///
 /// [prefix]: Prefix
-/// [`NsReader::resolve_attribute`]: crate::reader::NsReader::resolve_attribute
-/// [`NsReader::resolve_element`]: crate::reader::NsReader::resolve_element
 /// [`NsReader::read_resolved_event`]: crate::reader::NsReader::read_resolved_event
 /// [`NsReader::read_resolved_event_into`]: crate::reader::NsReader::read_resolved_event_into
 #[derive(Clone, PartialEq, Eq, Hash)]
@@ -1084,6 +1082,7 @@ impl<'a> Iterator for NamespaceBindingsIter<'a> {
 impl<'a> FusedIterator for NamespaceBindingsIter<'a> {}
 
 /// The previous name for [`NamespaceBindingsIter`].
+#[deprecated = "Use NamespaceBindingsIter instead. This alias will be removed in 0.40.0"]
 pub type PrefixIter<'a> = NamespaceBindingsIter<'a>;
 
 /// Iterator on the declared namespace bindings on specified level. Returns pairs of the _(prefix, namespace)_.

src/reader/ns_reader.rs

@@ -130,6 +130,7 @@ impl<R> NsReader<R> {
     /// # quick_xml::Result::Ok(())
     /// ```
     #[inline]
+    #[deprecated = "Use `.resolver().bindings()` instead. This method will be removed in 0.40.0"]
     pub const fn prefixes(&self) -> NamespaceBindingsIter<'_> {
         self.ns_resolver.bindings()
     }
@@ -241,6 +242,7 @@ impl<R> NsReader<R> {
     /// [`resolve_attribute()`]: Self::resolve_attribute()
     /// [`resolve_element()`]: Self::resolve_element()
     #[inline]
+    #[deprecated = "Use `.resolver().resolve()` instead. Note, that boolean argument should be inverted! This method will be removed in 0.40.0"]
     pub fn resolve<'n>(
         &self,
         name: QName<'n>,
@@ -301,6 +303,7 @@ impl<R> NsReader<R> {
     /// [`Unknown`]: ResolveResult::Unknown
     /// [`read_resolved_event()`]: Self::read_resolved_event
     #[inline]
+    #[deprecated = "Use `.resolver().resolve_element()` instead. This method will be removed in 0.40.0"]
     pub fn resolve_element<'n>(&self, name: QName<'n>) -> (ResolveResult<'_>, LocalName<'n>) {
         self.ns_resolver.resolve_element(name)
     }
@@ -371,6 +374,7 @@ impl<R> NsReader<R> {
     /// [`Unbound`]: ResolveResult::Unbound
     /// [`Unknown`]: ResolveResult::Unknown
     #[inline]
+    #[deprecated = "Use `.resolver().resolve_attribute()` instead. This method will be removed in 0.40.0"]
     pub fn resolve_attribute<'n>(&self, name: QName<'n>) -> (ResolveResult<'_>, LocalName<'n>) {
         self.ns_resolver.resolve_attribute(name)
     }