1//! Provides an `Element` type, which represents DOM nodes, and a builder to create them with.
2
3use std::io:: Write;
4use std::collections::{btree_map, BTreeMap};
5
6use std::str;
7use std::rc::Rc;
8use std::borrow::Cow;
9
10use error::{Error, ErrorKind, Result};
11
12use quick_xml::reader::Reader as EventReader;
13use quick_xml::events::{Event, BytesStart};
14
15use std::io::BufRead;
16
17use std::str::FromStr;
18
19use std::slice;
20
21use convert::{IntoElements, IntoAttributeValue, ElementEmitter};
22use namespace_set::NamespaceSet;
23
24/// Escape XML text
25pub fn write_escaped<W: Write>(writer: &mut W, input: &str) -> Result<()> {
26 for c in input.chars() {
27 match c {
28 '&' => write!(writer, "&")?,
29 '<' => write!(writer, "<")?,
30 '>' => write!(writer, ">")?,
31 '\'' => write!(writer, "'")?,
32 '"' => write!(writer, """)?,
33 _ => write!(writer, "{}", c)?,
34 }
35 }
36
37 Ok(())
38}
39
40/// A node in an element tree.
41#[derive(Clone, Debug, PartialEq, Eq)]
42pub enum Node {
43 /// An `Element`.
44 Element(Element),
45 /// A text node.
46 Text(String),
47}
48
49impl Node {
50 /// Turns this into an `Element` if possible, else returns None.
51 ///
52 /// # Examples
53 ///
54 /// ```rust
55 /// use minidom::Node;
56 ///
57 /// let elm = Node::Element("<meow />".parse().unwrap());
58 /// let txt = Node::Text("meow".to_owned());
59 ///
60 /// assert_eq!(elm.as_element().unwrap().name(), "meow");
61 /// assert_eq!(txt.as_element(), None);
62 /// ```
63 pub fn as_element(&self) -> Option<&Element> {
64 match *self {
65 Node::Element(ref e) => Some(e),
66 Node::Text(_) => None,
67 }
68 }
69
70 /// Turns this into a `String` if possible, else returns None.
71 ///
72 /// # Examples
73 ///
74 /// ```rust
75 /// use minidom::Node;
76 ///
77 /// let elm = Node::Element("<meow />".parse().unwrap());
78 /// let txt = Node::Text("meow".to_owned());
79 ///
80 /// assert_eq!(elm.as_text(), None);
81 /// assert_eq!(txt.as_text().unwrap(), "meow");
82 /// ```
83 pub fn as_text(&self) -> Option<&str> {
84 match *self {
85 Node::Element(_) => None,
86 Node::Text(ref s) => Some(s),
87 }
88 }
89
90 fn write_to_inner<W: Write>(&self, writer: &mut W) -> Result<()>{
91 match *self {
92 Node::Element(ref elmt) => elmt.write_to_inner(writer)?,
93 Node::Text(ref s) => write_escaped(writer, s)?,
94 }
95
96 Ok(())
97 }
98}
99
100#[derive(Clone, PartialEq, Eq, Debug)]
101/// A struct representing a DOM Element.
102pub struct Element {
103 prefix: Option<String>,
104 name: String,
105 namespaces: Rc<NamespaceSet>,
106 attributes: BTreeMap<String, String>,
107 children: Vec<Node>,
108}
109
110impl<'a> From<&'a Element> for String {
111 fn from(elem: &'a Element) -> String {
112 let mut writer = Vec::new();
113 elem.write_to(&mut writer).unwrap();
114 String::from_utf8(writer).unwrap()
115 }
116}
117
118
119impl FromStr for Element {
120 type Err = Error;
121
122 fn from_str(s: &str) -> Result<Element> {
123 let mut reader = EventReader::from_str(s);
124 Element::from_reader(&mut reader)
125 }
126}
127
128impl Element {
129 fn new<NS: Into<NamespaceSet>>(name: String, prefix: Option<String>, namespaces: NS, attributes: BTreeMap<String, String>, children: Vec<Node>) -> Element {
130 Element {
131 prefix, name,
132 namespaces: Rc::new(namespaces.into()),
133 attributes: attributes,
134 children: children,
135 }
136 }
137
138 /// Return a builder for an `Element` with the given `name`.
139 ///
140 /// # Examples
141 ///
142 /// ```rust
143 /// use minidom::Element;
144 ///
145 /// let elem = Element::builder("name")
146 /// .ns("namespace")
147 /// .attr("name", "value")
148 /// .append("inner")
149 /// .build();
150 ///
151 /// assert_eq!(elem.name(), "name");
152 /// assert_eq!(elem.ns(), Some("namespace".to_owned()));
153 /// assert_eq!(elem.attr("name"), Some("value"));
154 /// assert_eq!(elem.attr("inexistent"), None);
155 /// assert_eq!(elem.text(), "inner");
156 /// ```
157 pub fn builder<S: AsRef<str>>(name: S) -> ElementBuilder {
158 let (prefix, name) = split_element_name(name).unwrap();
159 ElementBuilder {
160 root: Element::new(name, prefix, None, BTreeMap::new(), Vec::new()),
161 namespaces: Default::default(),
162 }
163 }
164
165 /// Returns a bare minimum `Element` with this name.
166 ///
167 /// # Examples
168 ///
169 /// ```rust
170 /// use minidom::Element;
171 ///
172 /// let bare = Element::bare("name");
173 ///
174 /// assert_eq!(bare.name(), "name");
175 /// assert_eq!(bare.ns(), None);
176 /// assert_eq!(bare.attr("name"), None);
177 /// assert_eq!(bare.text(), "");
178 /// ```
179 pub fn bare<S: Into<String>>(name: S) -> Element {
180 Element {
181 prefix: None,
182 name: name.into(),
183 namespaces: Rc::new(NamespaceSet::default()),
184 attributes: BTreeMap::new(),
185 children: Vec::new(),
186 }
187 }
188
189 /// Returns a reference to the name of this element.
190 pub fn name(&self) -> &str {
191 &self.name
192 }
193
194 /// Returns a reference to the namespace of this element, if it has one, else `None`.
195 pub fn ns(&self) -> Option<String> {
196 self.namespaces.get(&self.prefix)
197 }
198
199 /// Returns a reference to the value of the given attribute, if it exists, else `None`.
200 pub fn attr(&self, name: &str) -> Option<&str> {
201 if let Some(value) = self.attributes.get(name) {
202 return Some(value)
203 }
204 None
205 }
206
207 /// Returns an iterator over the attributes of this element.
208 ///
209 /// # Example
210 ///
211 /// ```rust
212 /// use minidom::Element;
213 ///
214 /// let elm: Element = "<elem a=\"b\" />".parse().unwrap();
215 ///
216 /// let mut iter = elm.attrs();
217 ///
218 /// assert_eq!(iter.next().unwrap(), ("a", "b"));
219 /// assert_eq!(iter.next(), None);
220 /// ```
221 pub fn attrs(&self) -> Attrs {
222 Attrs {
223 iter: self.attributes.iter(),
224 }
225 }
226
227 /// Returns an iterator over the attributes of this element, with the value being a mutable
228 /// reference.
229 pub fn attrs_mut(&mut self) -> AttrsMut {
230 AttrsMut {
231 iter: self.attributes.iter_mut(),
232 }
233 }
234
235 /// Modifies the value of an attribute.
236 pub fn set_attr<S: Into<String>, V: IntoAttributeValue>(&mut self, name: S, val: V) {
237 let name = name.into();
238 let val = val.into_attribute_value();
239
240 if let Some(value) = self.attributes.get_mut(&name) {
241 *value = val.expect("removing existing value via set_attr, this is not yet supported (TODO)"); // TODO
242 return;
243 }
244
245 if let Some(val) = val {
246 self.attributes.insert(name, val);
247 }
248 }
249
250 /// Returns whether the element has the given name and namespace.
251 ///
252 /// # Examples
253 ///
254 /// ```rust
255 /// use minidom::Element;
256 ///
257 /// let elem = Element::builder("name").ns("namespace").build();
258 ///
259 /// assert_eq!(elem.is("name", "namespace"), true);
260 /// assert_eq!(elem.is("name", "wrong"), false);
261 /// assert_eq!(elem.is("wrong", "namespace"), false);
262 /// assert_eq!(elem.is("wrong", "wrong"), false);
263 /// ```
264 pub fn is<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> bool {
265 self.name == name.as_ref() &&
266 self.has_ns(namespace)
267 }
268
269 /// Returns whether the element has the given namespace.
270 ///
271 /// # Examples
272 ///
273 /// ```rust
274 /// use minidom::Element;
275 ///
276 /// let elem = Element::builder("name").ns("namespace").build();
277 ///
278 /// assert_eq!(elem.has_ns("namespace"), true);
279 /// assert_eq!(elem.has_ns("wrong"), false);
280 /// ```
281 pub fn has_ns<NS: AsRef<str>>(&self, namespace: NS) -> bool {
282 self.namespaces.has(&self.prefix, namespace)
283 }
284
285 /// Parse a document from an `EventReader`.
286 pub fn from_reader<R: BufRead>(reader: &mut EventReader<R>) -> Result<Element> {
287 let mut buf = Vec::new();
288
289 let root: Element = loop {
290 let e = reader.read_event(&mut buf)?;
291 match e {
292 Event::Empty(ref e) | Event::Start(ref e) => {
293 break build_element(&reader, e)?;
294 },
295 Event::Eof => {
296 bail!(ErrorKind::EndOfDocument);
297 },
298 _ => (), // TODO: may need more errors
299 }
300 };
301
302 let mut stack = vec![root];
303
304 loop {
305 match reader.read_event(&mut buf)? {
306 Event::Empty(ref e) => {
307 let elem = build_element(&reader, e)?;
308 // Since there is no Event::End after, directly append it to the current node
309 stack.last_mut().unwrap().append_child(elem);
310 },
311 Event::Start(ref e) => {
312 let elem = build_element(&reader, e)?;
313 stack.push(elem);
314 },
315 Event::End(ref e) => {
316 if stack.len() <= 1 {
317 break;
318 }
319 let elem = stack.pop().unwrap();
320 if let Some(to) = stack.last_mut() {
321 if elem.name().as_bytes() != e.name() {
322 bail!(ErrorKind::InvalidElementClosed);
323 }
324 to.append_child(elem);
325 }
326 },
327 Event::Text(s) | Event::CData(s) => {
328 let text = s.unescape_and_decode(reader)?;
329 if text != "" {
330 let mut current_elem = stack.last_mut().unwrap();
331 current_elem.append_text_node(text);
332 }
333 },
334 Event::Eof => {
335 break;
336 },
337 _ => (), // TODO: may need to implement more
338 }
339 }
340 Ok(stack.pop().unwrap())
341 }
342
343 /// Output a document to a `Writer`.
344 pub fn write_to<W: Write>(&self, writer: &mut W) -> Result<()> {
345 write!(writer, "<?xml version=\"1.0\" encoding=\"utf-8\"?>")?;
346 self.write_to_inner(writer)
347 }
348
349 /// Like `write_to()` but without the `<?xml?>` prelude
350 pub fn write_to_inner<W: Write>(&self, writer: &mut W) -> Result<()> {
351 let name = match &self.prefix {
352 &None => Cow::Borrowed(&self.name),
353 &Some(ref prefix) => Cow::Owned(format!("{}:{}", prefix, self.name)),
354 };
355 write!(writer, "<{}", name)?;
356
357 for (prefix, ns) in self.namespaces.declared_ns() {
358 match prefix {
359 &None => {
360 write!(writer, " xmlns=\"")?;
361 write_escaped(writer, ns)?;
362 write!(writer, "\"")?;
363 },
364 &Some(ref prefix) => {
365 write!(writer, " xmlns:{}=\"", prefix)?;
366 write_escaped(writer, ns)?;
367 write!(writer, "\"")?;
368 },
369 }
370 }
371
372 for (key, value) in &self.attributes {
373 write!(writer, " {}=\"", key)?;
374 write_escaped(writer, value)?;
375 write!(writer, "\"")?;
376 }
377
378 if self.children.is_empty() {
379 write!(writer, " />")?;
380 return Ok(())
381 }
382
383 write!(writer, ">")?;
384
385 for child in &self.children {
386 child.write_to_inner(writer)?;
387 }
388
389 write!(writer, "</{}>", name)?;
390 Ok(())
391 }
392
393 /// Returns an iterator over references to every child node of this element.
394 ///
395 /// # Examples
396 ///
397 /// ```rust
398 /// use minidom::Element;
399 ///
400 /// let elem: Element = "<root>a<c1 />b<c2 />c</root>".parse().unwrap();
401 ///
402 /// let mut iter = elem.nodes();
403 ///
404 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "a");
405 /// assert_eq!(iter.next().unwrap().as_element().unwrap().name(), "c1");
406 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "b");
407 /// assert_eq!(iter.next().unwrap().as_element().unwrap().name(), "c2");
408 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "c");
409 /// assert_eq!(iter.next(), None);
410 /// ```
411 #[inline] pub fn nodes(&self) -> Nodes {
412 self.children.iter()
413 }
414
415 /// Returns an iterator over mutable references to every child node of this element.
416 #[inline] pub fn nodes_mut(&mut self) -> NodesMut {
417 self.children.iter_mut()
418 }
419
420 /// Returns an iterator over references to every child element of this element.
421 ///
422 /// # Examples
423 ///
424 /// ```rust
425 /// use minidom::Element;
426 ///
427 /// let elem: Element = "<root>hello<child1 />this<child2 />is<child3 />ignored</root>".parse().unwrap();
428 ///
429 /// let mut iter = elem.children();
430 /// assert_eq!(iter.next().unwrap().name(), "child1");
431 /// assert_eq!(iter.next().unwrap().name(), "child2");
432 /// assert_eq!(iter.next().unwrap().name(), "child3");
433 /// assert_eq!(iter.next(), None);
434 /// ```
435 #[inline] pub fn children(&self) -> Children {
436 Children {
437 iter: self.children.iter(),
438 }
439 }
440
441 /// Returns an iterator over mutable references to every child element of this element.
442 #[inline] pub fn children_mut(&mut self) -> ChildrenMut {
443 ChildrenMut {
444 iter: self.children.iter_mut(),
445 }
446 }
447
448 /// Returns an iterator over references to every text node of this element.
449 ///
450 /// # Examples
451 ///
452 /// ```rust
453 /// use minidom::Element;
454 ///
455 /// let elem: Element = "<root>hello<c /> world!</root>".parse().unwrap();
456 ///
457 /// let mut iter = elem.texts();
458 /// assert_eq!(iter.next().unwrap(), "hello");
459 /// assert_eq!(iter.next().unwrap(), " world!");
460 /// assert_eq!(iter.next(), None);
461 /// ```
462 #[inline] pub fn texts(&self) -> Texts {
463 Texts {
464 iter: self.children.iter(),
465 }
466 }
467
468 /// Returns an iterator over mutable references to every text node of this element.
469 #[inline] pub fn texts_mut(&mut self) -> TextsMut {
470 TextsMut {
471 iter: self.children.iter_mut(),
472 }
473 }
474
475 /// Appends a child node to the `Element`, returning the appended node.
476 ///
477 /// # Examples
478 ///
479 /// ```rust
480 /// use minidom::Element;
481 ///
482 /// let mut elem = Element::bare("root");
483 ///
484 /// assert_eq!(elem.children().count(), 0);
485 ///
486 /// elem.append_child(Element::bare("child"));
487 ///
488 /// {
489 /// let mut iter = elem.children();
490 /// assert_eq!(iter.next().unwrap().name(), "child");
491 /// assert_eq!(iter.next(), None);
492 /// }
493 ///
494 /// let child = elem.append_child(Element::bare("new"));
495 ///
496 /// assert_eq!(child.name(), "new");
497 /// ```
498 pub fn append_child(&mut self, child: Element) -> &mut Element {
499 child.namespaces.set_parent(self.namespaces.clone());
500
501 self.children.push(Node::Element(child));
502 if let Node::Element(ref mut cld) = *self.children.last_mut().unwrap() {
503 cld
504 } else {
505 unreachable!()
506 }
507 }
508
509 /// Appends a text node to an `Element`.
510 ///
511 /// # Examples
512 ///
513 /// ```rust
514 /// use minidom::Element;
515 ///
516 /// let mut elem = Element::bare("node");
517 ///
518 /// assert_eq!(elem.text(), "");
519 ///
520 /// elem.append_text_node("text");
521 ///
522 /// assert_eq!(elem.text(), "text");
523 /// ```
524 pub fn append_text_node<S: Into<String>>(&mut self, child: S) {
525 self.children.push(Node::Text(child.into()));
526 }
527
528 /// Appends a node to an `Element`.
529 ///
530 /// # Examples
531 ///
532 /// ```rust
533 /// use minidom::{Element, Node};
534 ///
535 /// let mut elem = Element::bare("node");
536 ///
537 /// elem.append_node(Node::Text("hello".to_owned()));
538 ///
539 /// assert_eq!(elem.text(), "hello");
540 /// ```
541 pub fn append_node(&mut self, node: Node) {
542 self.children.push(node);
543 }
544
545 /// Returns the concatenation of all text nodes in the `Element`.
546 ///
547 /// # Examples
548 ///
549 /// ```rust
550 /// use minidom::Element;
551 ///
552 /// let elem: Element = "<node>hello,<split /> world!</node>".parse().unwrap();
553 ///
554 /// assert_eq!(elem.text(), "hello, world!");
555 /// ```
556 pub fn text(&self) -> String {
557 self.texts().fold(String::new(), |ret, new| ret + new)
558 }
559
560 /// Returns a reference to the first child element with the specific name and namespace, if it
561 /// exists in the direct descendants of this `Element`, else returns `None`.
562 ///
563 /// # Examples
564 ///
565 /// ```rust
566 /// use minidom::Element;
567 ///
568 /// let elem: Element = r#"<node xmlns="ns"><a /><a xmlns="other_ns" /><b /></node>"#.parse().unwrap();
569 ///
570 /// assert!(elem.get_child("a", "ns").unwrap().is("a", "ns"));
571 /// assert!(elem.get_child("a", "other_ns").unwrap().is("a", "other_ns"));
572 /// assert!(elem.get_child("b", "ns").unwrap().is("b", "ns"));
573 /// assert_eq!(elem.get_child("c", "ns"), None);
574 /// assert_eq!(elem.get_child("b", "other_ns"), None);
575 /// assert_eq!(elem.get_child("a", "inexistent_ns"), None);
576 /// ```
577 pub fn get_child<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> Option<&Element> {
578 for fork in &self.children {
579 if let Node::Element(ref e) = *fork {
580 if e.is(name.as_ref(), namespace.as_ref()) {
581 return Some(e);
582 }
583 }
584 }
585 None
586 }
587
588 /// Returns a mutable reference to the first child element with the specific name and namespace,
589 /// if it exists in the direct descendants of this `Element`, else returns `None`.
590 pub fn get_child_mut<N: AsRef<str>, NS: AsRef<str>>(&mut self, name: N, namespace: NS) -> Option<&mut Element> {
591 for fork in &mut self.children {
592 if let Node::Element(ref mut e) = *fork {
593 if e.is(name.as_ref(), namespace.as_ref()) {
594 return Some(e);
595 }
596 }
597 }
598 None
599 }
600
601 /// Returns whether a specific child with this name and namespace exists in the direct
602 /// descendants of the `Element`.
603 ///
604 /// # Examples
605 ///
606 /// ```rust
607 /// use minidom::Element;
608 ///
609 /// let elem: Element = r#"<node xmlns="ns"><a /><a xmlns="other_ns" /><b /></node>"#.parse().unwrap();
610 ///
611 /// assert_eq!(elem.has_child("a", "other_ns"), true);
612 /// assert_eq!(elem.has_child("a", "ns"), true);
613 /// assert_eq!(elem.has_child("a", "inexistent_ns"), false);
614 /// assert_eq!(elem.has_child("b", "ns"), true);
615 /// assert_eq!(elem.has_child("b", "other_ns"), false);
616 /// assert_eq!(elem.has_child("b", "inexistent_ns"), false);
617 /// ```
618 pub fn has_child<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> bool {
619 self.get_child(name, namespace).is_some()
620 }
621}
622
623fn split_element_name<S: AsRef<str>>(s: S) -> Result<(Option<String>, String)> {
624 let name_parts = s.as_ref().split(':').collect::<Vec<&str>>();
625 match name_parts.len() {
626 2 => Ok((Some(name_parts[0].to_owned()), name_parts[1].to_owned())),
627 1 => Ok((None, name_parts[0].to_owned())),
628 _ => bail!(ErrorKind::InvalidElement),
629 }
630}
631
632fn build_element<R: BufRead>(reader: &EventReader<R>, event: &BytesStart) -> Result<Element> {
633 let mut namespaces = BTreeMap::new();
634 let attributes = event.attributes()
635 .map(|o| {
636 let o = o?;
637 let key = str::from_utf8(o.key)?.to_owned();
638 let value = o.unescape_and_decode_value(reader)?;
639 Ok((key, value))
640 })
641 .filter(|o| {
642 match o {
643 &Ok((ref key, ref value)) if key == "xmlns" => {
644 namespaces.insert(None, value.to_owned());
645 false
646 },
647 &Ok((ref key, ref value)) if key.starts_with("xmlns:") => {
648 namespaces.insert(Some(key[6..].to_owned()), value.to_owned());
649 false
650 },
651 _ => true,
652 }
653 })
654 .collect::<Result<BTreeMap<String, String>>>()?;
655
656 let (prefix, name) = split_element_name(str::from_utf8(event.name())?)?;
657 let element = Element::new(name, prefix, namespaces, attributes, Vec::new());
658 Ok(element)
659}
660
661/// An iterator over references to child elements of an `Element`.
662pub struct Children<'a> {
663 iter: slice::Iter<'a, Node>,
664}
665
666impl<'a> Iterator for Children<'a> {
667 type Item = &'a Element;
668
669 fn next(&mut self) -> Option<&'a Element> {
670 for item in &mut self.iter {
671 if let Node::Element(ref child) = *item {
672 return Some(child);
673 }
674 }
675 None
676 }
677}
678
679/// An iterator over mutable references to child elements of an `Element`.
680pub struct ChildrenMut<'a> {
681 iter: slice::IterMut<'a, Node>,
682}
683
684impl<'a> Iterator for ChildrenMut<'a> {
685 type Item = &'a mut Element;
686
687 fn next(&mut self) -> Option<&'a mut Element> {
688 for item in &mut self.iter {
689 if let Node::Element(ref mut child) = *item {
690 return Some(child);
691 }
692 }
693 None
694 }
695}
696
697/// An iterator over references to child text nodes of an `Element`.
698pub struct Texts<'a> {
699 iter: slice::Iter<'a, Node>,
700}
701
702impl<'a> Iterator for Texts<'a> {
703 type Item = &'a str;
704
705 fn next(&mut self) -> Option<&'a str> {
706 for item in &mut self.iter {
707 if let Node::Text(ref child) = *item {
708 return Some(child);
709 }
710 }
711 None
712 }
713}
714
715/// An iterator over mutable references to child text nodes of an `Element`.
716pub struct TextsMut<'a> {
717 iter: slice::IterMut<'a, Node>,
718}
719
720impl<'a> Iterator for TextsMut<'a> {
721 type Item = &'a mut String;
722
723 fn next(&mut self) -> Option<&'a mut String> {
724 for item in &mut self.iter {
725 if let Node::Text(ref mut child) = *item {
726 return Some(child);
727 }
728 }
729 None
730 }
731}
732
733/// An iterator over references to all child nodes of an `Element`.
734pub type Nodes<'a> = slice::Iter<'a, Node>;
735
736/// An iterator over mutable references to all child nodes of an `Element`.
737pub type NodesMut<'a> = slice::IterMut<'a, Node>;
738
739/// An iterator over the attributes of an `Element`.
740pub struct Attrs<'a> {
741 iter: btree_map::Iter<'a, String, String>,
742}
743
744impl<'a> Iterator for Attrs<'a> {
745 type Item = (&'a str, &'a str);
746
747 fn next(&mut self) -> Option<Self::Item> {
748 self.iter.next().map(|(x, y)| (x.as_ref(), y.as_ref()))
749 }
750}
751
752/// An iterator over the attributes of an `Element`, with the values mutable.
753pub struct AttrsMut<'a> {
754 iter: btree_map::IterMut<'a, String, String>,
755}
756
757impl<'a> Iterator for AttrsMut<'a> {
758 type Item = (&'a str, &'a mut String);
759
760 fn next(&mut self) -> Option<Self::Item> {
761 self.iter.next().map(|(x, y)| (x.as_ref(), y))
762 }
763}
764
765/// A builder for `Element`s.
766pub struct ElementBuilder {
767 root: Element,
768 namespaces: BTreeMap<Option<String>, String>,
769}
770
771impl ElementBuilder {
772 /// Sets the namespace.
773 pub fn ns<S: Into<String>>(mut self, namespace: S) -> ElementBuilder {
774 self.namespaces
775 .insert(self.root.prefix.clone(), namespace.into());
776 self
777 }
778
779 /// Sets an attribute.
780 pub fn attr<S: Into<String>, V: IntoAttributeValue>(mut self, name: S, value: V) -> ElementBuilder {
781 self.root.set_attr(name, value);
782 self
783 }
784
785 /// Appends anything implementing `IntoElements` into the tree.
786 pub fn append<T: IntoElements>(mut self, into: T) -> ElementBuilder {
787 {
788 let mut emitter = ElementEmitter::new(&mut self.root);
789 into.into_elements(&mut emitter);
790 }
791 self
792 }
793
794 /// Builds the `Element`.
795 pub fn build(self) -> Element {
796 let mut element = self.root;
797 // Set namespaces
798 element.namespaces = Rc::new(NamespaceSet::from(self.namespaces));
799 // Propagate namespaces
800 for node in &element.children {
801 if let Node::Element(ref e) = *node {
802 e.namespaces.set_parent(element.namespaces.clone());
803 }
804 }
805
806 element
807 }
808}
809
810#[cfg(test)]
811#[test]
812fn test_element_new() {
813 use std::iter::FromIterator;
814
815 let elem = Element::new( "name".to_owned()
816 , None
817 , Some("namespace".to_owned())
818 , BTreeMap::from_iter(vec![ ("name".to_string(), "value".to_string()) ].into_iter() )
819 , Vec::new() );
820
821 assert_eq!(elem.name(), "name");
822 assert_eq!(elem.ns(), Some("namespace".to_owned()));
823 assert_eq!(elem.attr("name"), Some("value"));
824 assert_eq!(elem.attr("inexistent"), None);
825}