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.namespaces.has(&self.prefix, namespace)
267 }
268
269 /// Parse a document from an `EventReader`.
270 pub fn from_reader<R: BufRead>(reader: &mut EventReader<R>) -> Result<Element> {
271 let mut buf = Vec::new();
272 let root: Element;
273
274 loop {
275 let e = reader.read_event(&mut buf)?;
276 match e {
277 Event::Empty(ref e) | Event::Start(ref e) => {
278 root = build_element(e)?; // FIXME: could be break build_element(e)? when break value is stable
279 break;
280 },
281 Event::Eof => {
282 bail!(ErrorKind::EndOfDocument);
283 },
284 _ => () // TODO: may need more errors
285 }
286 };
287
288 let mut stack = vec![root];
289
290 loop {
291 match reader.read_event(&mut buf)? {
292 Event::Empty(ref e) => {
293 let elem = build_element(e)?;
294 // Since there is no Event::End after, directly append it to the current node
295 stack.last_mut().unwrap().append_child(elem);
296 },
297 Event::Start(ref e) => {
298 let elem = build_element(e)?;
299 stack.push(elem);
300 },
301 Event::End(ref e) => {
302 if stack.len() <= 1 {
303 break;
304 }
305 let elem = stack.pop().unwrap();
306 if let Some(to) = stack.last_mut() {
307 if elem.name().as_bytes() != e.name() {
308 bail!(ErrorKind::InvalidElementClosed);
309 }
310 to.append_child(elem);
311 }
312 },
313 Event::Text(s) | Event::CData(s) => {
314 let text = s.unescape_and_decode(reader)?;
315 if text != "" {
316 let mut current_elem = stack.last_mut().unwrap();
317 current_elem.append_text_node(text);
318 }
319 },
320 Event::Eof => {
321 break;
322 },
323 _ => (), // TODO: may need to implement more
324 }
325 }
326 Ok(stack.pop().unwrap())
327 }
328
329 /// Output a document to a `Writer`.
330 pub fn write_to<W: Write>(&self, writer: &mut W) -> Result<()> {
331 write!(writer, "<?xml version=\"1.0\" encoding=\"utf-8\"?>")?;
332 self.write_to_inner(writer)
333 }
334
335 /// Like `write_to()` but without the `<?xml?>` prelude
336 pub fn write_to_inner<W: Write>(&self, writer: &mut W) -> Result<()> {
337 let name = match &self.prefix {
338 &None => Cow::Borrowed(&self.name),
339 &Some(ref prefix) => Cow::Owned(format!("{}:{}", prefix, self.name)),
340 };
341 write!(writer, "<{}", name)?;
342
343 for (prefix, ns) in self.namespaces.declared_ns() {
344 match prefix {
345 &None => {
346 write!(writer, " xmlns=\"")?;
347 write_escaped(writer, ns)?;
348 write!(writer, "\"")?;
349 },
350 &Some(ref prefix) => {
351 write!(writer, " xmlns:{}=\"", prefix)?;
352 write_escaped(writer, ns)?;
353 write!(writer, "\"")?;
354 },
355 }
356 }
357
358 for (key, value) in &self.attributes {
359 write!(writer, " {}=\"", key)?;
360 write_escaped(writer, value)?;
361 write!(writer, "\"")?;
362 }
363
364 if self.children.is_empty() {
365 write!(writer, " />")?;
366 return Ok(())
367 }
368
369 write!(writer, ">")?;
370
371 for child in &self.children {
372 child.write_to_inner(writer)?;
373 }
374
375 write!(writer, "</{}>", name)?;
376 Ok(())
377 }
378
379 /// Returns an iterator over references to every child node of this element.
380 ///
381 /// # Examples
382 ///
383 /// ```rust
384 /// use minidom::Element;
385 ///
386 /// let elem: Element = "<root>a<c1 />b<c2 />c</root>".parse().unwrap();
387 ///
388 /// let mut iter = elem.nodes();
389 ///
390 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "a");
391 /// assert_eq!(iter.next().unwrap().as_element().unwrap().name(), "c1");
392 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "b");
393 /// assert_eq!(iter.next().unwrap().as_element().unwrap().name(), "c2");
394 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "c");
395 /// assert_eq!(iter.next(), None);
396 /// ```
397 #[inline] pub fn nodes(&self) -> Nodes {
398 self.children.iter()
399 }
400
401 /// Returns an iterator over mutable references to every child node of this element.
402 #[inline] pub fn nodes_mut(&mut self) -> NodesMut {
403 self.children.iter_mut()
404 }
405
406 /// Returns an iterator over references to every child element of this element.
407 ///
408 /// # Examples
409 ///
410 /// ```rust
411 /// use minidom::Element;
412 ///
413 /// let elem: Element = "<root>hello<child1 />this<child2 />is<child3 />ignored</root>".parse().unwrap();
414 ///
415 /// let mut iter = elem.children();
416 /// assert_eq!(iter.next().unwrap().name(), "child1");
417 /// assert_eq!(iter.next().unwrap().name(), "child2");
418 /// assert_eq!(iter.next().unwrap().name(), "child3");
419 /// assert_eq!(iter.next(), None);
420 /// ```
421 #[inline] pub fn children(&self) -> Children {
422 Children {
423 iter: self.children.iter(),
424 }
425 }
426
427 /// Returns an iterator over mutable references to every child element of this element.
428 #[inline] pub fn children_mut(&mut self) -> ChildrenMut {
429 ChildrenMut {
430 iter: self.children.iter_mut(),
431 }
432 }
433
434 /// Returns an iterator over references to every text node of this element.
435 ///
436 /// # Examples
437 ///
438 /// ```rust
439 /// use minidom::Element;
440 ///
441 /// let elem: Element = "<root>hello<c /> world!</root>".parse().unwrap();
442 ///
443 /// let mut iter = elem.texts();
444 /// assert_eq!(iter.next().unwrap(), "hello");
445 /// assert_eq!(iter.next().unwrap(), " world!");
446 /// assert_eq!(iter.next(), None);
447 /// ```
448 #[inline] pub fn texts(&self) -> Texts {
449 Texts {
450 iter: self.children.iter(),
451 }
452 }
453
454 /// Returns an iterator over mutable references to every text node of this element.
455 #[inline] pub fn texts_mut(&mut self) -> TextsMut {
456 TextsMut {
457 iter: self.children.iter_mut(),
458 }
459 }
460
461 /// Appends a child node to the `Element`, returning the appended node.
462 ///
463 /// # Examples
464 ///
465 /// ```rust
466 /// use minidom::Element;
467 ///
468 /// let mut elem = Element::bare("root");
469 ///
470 /// assert_eq!(elem.children().count(), 0);
471 ///
472 /// elem.append_child(Element::bare("child"));
473 ///
474 /// {
475 /// let mut iter = elem.children();
476 /// assert_eq!(iter.next().unwrap().name(), "child");
477 /// assert_eq!(iter.next(), None);
478 /// }
479 ///
480 /// let child = elem.append_child(Element::bare("new"));
481 ///
482 /// assert_eq!(child.name(), "new");
483 /// ```
484 pub fn append_child(&mut self, child: Element) -> &mut Element {
485 child.namespaces.set_parent(self.namespaces.clone());
486
487 self.children.push(Node::Element(child));
488 if let Node::Element(ref mut cld) = *self.children.last_mut().unwrap() {
489 cld
490 } else {
491 unreachable!()
492 }
493 }
494
495 /// Appends a text node to an `Element`.
496 ///
497 /// # Examples
498 ///
499 /// ```rust
500 /// use minidom::Element;
501 ///
502 /// let mut elem = Element::bare("node");
503 ///
504 /// assert_eq!(elem.text(), "");
505 ///
506 /// elem.append_text_node("text");
507 ///
508 /// assert_eq!(elem.text(), "text");
509 /// ```
510 pub fn append_text_node<S: Into<String>>(&mut self, child: S) {
511 self.children.push(Node::Text(child.into()));
512 }
513
514 /// Appends a node to an `Element`.
515 ///
516 /// # Examples
517 ///
518 /// ```rust
519 /// use minidom::{Element, Node};
520 ///
521 /// let mut elem = Element::bare("node");
522 ///
523 /// elem.append_node(Node::Text("hello".to_owned()));
524 ///
525 /// assert_eq!(elem.text(), "hello");
526 /// ```
527 pub fn append_node(&mut self, node: Node) {
528 self.children.push(node);
529 }
530
531 /// Returns the concatenation of all text nodes in the `Element`.
532 ///
533 /// # Examples
534 ///
535 /// ```rust
536 /// use minidom::Element;
537 ///
538 /// let elem: Element = "<node>hello,<split /> world!</node>".parse().unwrap();
539 ///
540 /// assert_eq!(elem.text(), "hello, world!");
541 /// ```
542 pub fn text(&self) -> String {
543 self.texts().fold(String::new(), |ret, new| ret + new)
544 }
545
546 /// Returns a reference to the first child element with the specific name and namespace, if it
547 /// exists in the direct descendants of this `Element`, else returns `None`.
548 ///
549 /// # Examples
550 ///
551 /// ```rust
552 /// use minidom::Element;
553 ///
554 /// let elem: Element = r#"<node xmlns="ns"><a /><a xmlns="other_ns" /><b /></node>"#.parse().unwrap();
555 ///
556 /// assert!(elem.get_child("a", "ns").unwrap().is("a", "ns"));
557 /// assert!(elem.get_child("a", "other_ns").unwrap().is("a", "other_ns"));
558 /// assert!(elem.get_child("b", "ns").unwrap().is("b", "ns"));
559 /// assert_eq!(elem.get_child("c", "ns"), None);
560 /// assert_eq!(elem.get_child("b", "other_ns"), None);
561 /// assert_eq!(elem.get_child("a", "inexistent_ns"), None);
562 /// ```
563 pub fn get_child<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> Option<&Element> {
564 for fork in &self.children {
565 if let Node::Element(ref e) = *fork {
566 if e.is(name.as_ref(), namespace.as_ref()) {
567 return Some(e);
568 }
569 }
570 }
571 None
572 }
573
574 /// Returns a mutable reference to the first child element with the specific name and namespace,
575 /// if it exists in the direct descendants of this `Element`, else returns `None`.
576 pub fn get_child_mut<N: AsRef<str>, NS: AsRef<str>>(&mut self, name: N, namespace: NS) -> Option<&mut Element> {
577 for fork in &mut self.children {
578 if let Node::Element(ref mut e) = *fork {
579 if e.is(name.as_ref(), namespace.as_ref()) {
580 return Some(e);
581 }
582 }
583 }
584 None
585 }
586
587 /// Returns whether a specific child with this name and namespace exists in the direct
588 /// descendants of the `Element`.
589 ///
590 /// # Examples
591 ///
592 /// ```rust
593 /// use minidom::Element;
594 ///
595 /// let elem: Element = r#"<node xmlns="ns"><a /><a xmlns="other_ns" /><b /></node>"#.parse().unwrap();
596 ///
597 /// assert_eq!(elem.has_child("a", "other_ns"), true);
598 /// assert_eq!(elem.has_child("a", "ns"), true);
599 /// assert_eq!(elem.has_child("a", "inexistent_ns"), false);
600 /// assert_eq!(elem.has_child("b", "ns"), true);
601 /// assert_eq!(elem.has_child("b", "other_ns"), false);
602 /// assert_eq!(elem.has_child("b", "inexistent_ns"), false);
603 /// ```
604 pub fn has_child<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> bool {
605 self.get_child(name, namespace).is_some()
606 }
607}
608
609fn split_element_name<S: AsRef<str>>(s: S) -> Result<(Option<String>, String)> {
610 let name_parts = s.as_ref().split(':').collect::<Vec<&str>>();
611 match name_parts.len() {
612 2 => Ok((Some(name_parts[0].to_owned()), name_parts[1].to_owned())),
613 1 => Ok((None, name_parts[0].to_owned())),
614 _ => bail!(ErrorKind::InvalidElement),
615 }
616}
617
618fn build_element(event: &BytesStart) -> Result<Element> {
619 let mut namespaces = BTreeMap::new();
620 let attributes = event.attributes()
621 .map(|o| {
622 let o = o?;
623 let key = str::from_utf8(o.key)?.to_owned();
624 let value = str::from_utf8(o.value)?.to_owned();
625 Ok((key, value))
626 })
627 .filter(|o| {
628 match o {
629 &Ok((ref key, ref value)) if key == "xmlns" => {
630 namespaces.insert(None, value.to_owned());
631 false
632 },
633 &Ok((ref key, ref value)) if key.starts_with("xmlns:") => {
634 namespaces.insert(Some(key[6..].to_owned()), value.to_owned());
635 false
636 },
637 _ => true,
638 }
639 })
640 .collect::<Result<BTreeMap<String, String>>>()?;
641
642 let (prefix, name) = split_element_name(str::from_utf8(event.name())?)?;
643 let element = Element::new(name, prefix, namespaces, attributes, Vec::new());
644 Ok(element)
645}
646
647/// An iterator over references to child elements of an `Element`.
648pub struct Children<'a> {
649 iter: slice::Iter<'a, Node>,
650}
651
652impl<'a> Iterator for Children<'a> {
653 type Item = &'a Element;
654
655 fn next(&mut self) -> Option<&'a Element> {
656 for item in &mut self.iter {
657 if let Node::Element(ref child) = *item {
658 return Some(child);
659 }
660 }
661 None
662 }
663}
664
665/// An iterator over mutable references to child elements of an `Element`.
666pub struct ChildrenMut<'a> {
667 iter: slice::IterMut<'a, Node>,
668}
669
670impl<'a> Iterator for ChildrenMut<'a> {
671 type Item = &'a mut Element;
672
673 fn next(&mut self) -> Option<&'a mut Element> {
674 for item in &mut self.iter {
675 if let Node::Element(ref mut child) = *item {
676 return Some(child);
677 }
678 }
679 None
680 }
681}
682
683/// An iterator over references to child text nodes of an `Element`.
684pub struct Texts<'a> {
685 iter: slice::Iter<'a, Node>,
686}
687
688impl<'a> Iterator for Texts<'a> {
689 type Item = &'a str;
690
691 fn next(&mut self) -> Option<&'a str> {
692 for item in &mut self.iter {
693 if let Node::Text(ref child) = *item {
694 return Some(child);
695 }
696 }
697 None
698 }
699}
700
701/// An iterator over mutable references to child text nodes of an `Element`.
702pub struct TextsMut<'a> {
703 iter: slice::IterMut<'a, Node>,
704}
705
706impl<'a> Iterator for TextsMut<'a> {
707 type Item = &'a mut String;
708
709 fn next(&mut self) -> Option<&'a mut String> {
710 for item in &mut self.iter {
711 if let Node::Text(ref mut child) = *item {
712 return Some(child);
713 }
714 }
715 None
716 }
717}
718
719/// An iterator over references to all child nodes of an `Element`.
720pub type Nodes<'a> = slice::Iter<'a, Node>;
721
722/// An iterator over mutable references to all child nodes of an `Element`.
723pub type NodesMut<'a> = slice::IterMut<'a, Node>;
724
725/// An iterator over the attributes of an `Element`.
726pub struct Attrs<'a> {
727 iter: btree_map::Iter<'a, String, String>,
728}
729
730impl<'a> Iterator for Attrs<'a> {
731 type Item = (&'a str, &'a str);
732
733 fn next(&mut self) -> Option<Self::Item> {
734 self.iter.next().map(|(x, y)| (x.as_ref(), y.as_ref()))
735 }
736}
737
738/// An iterator over the attributes of an `Element`, with the values mutable.
739pub struct AttrsMut<'a> {
740 iter: btree_map::IterMut<'a, String, String>,
741}
742
743impl<'a> Iterator for AttrsMut<'a> {
744 type Item = (&'a str, &'a mut String);
745
746 fn next(&mut self) -> Option<Self::Item> {
747 self.iter.next().map(|(x, y)| (x.as_ref(), y))
748 }
749}
750
751/// A builder for `Element`s.
752pub struct ElementBuilder {
753 root: Element,
754 namespaces: BTreeMap<Option<String>, String>,
755}
756
757impl ElementBuilder {
758 /// Sets the namespace.
759 pub fn ns<S: Into<String>>(mut self, namespace: S) -> ElementBuilder {
760 self.namespaces
761 .insert(self.root.prefix.clone(), namespace.into());
762 self
763 }
764
765 /// Sets an attribute.
766 pub fn attr<S: Into<String>, V: IntoAttributeValue>(mut self, name: S, value: V) -> ElementBuilder {
767 self.root.set_attr(name, value);
768 self
769 }
770
771 /// Appends anything implementing `IntoElements` into the tree.
772 pub fn append<T: IntoElements>(mut self, into: T) -> ElementBuilder {
773 {
774 let mut emitter = ElementEmitter::new(&mut self.root);
775 into.into_elements(&mut emitter);
776 }
777 self
778 }
779
780 /// Builds the `Element`.
781 pub fn build(self) -> Element {
782 let mut element = self.root;
783 // Set namespaces
784 element.namespaces = Rc::new(NamespaceSet::from(self.namespaces));
785 // Propagate namespaces
786 for node in &element.children {
787 if let Node::Element(ref e) = *node {
788 e.namespaces.set_parent(element.namespaces.clone());
789 }
790 }
791
792 element
793 }
794}
795
796#[cfg(test)]
797#[test]
798fn test_element_new() {
799 use std::iter::FromIterator;
800
801 let elem = Element::new( "name".to_owned()
802 , None
803 , Some("namespace".to_owned())
804 , BTreeMap::from_iter(vec![ ("name".to_string(), "value".to_string()) ].into_iter() )
805 , Vec::new() );
806
807 assert_eq!(elem.name(), "name");
808 assert_eq!(elem.ns(), Some("namespace".to_owned()));
809 assert_eq!(elem.attr("name"), Some("value"));
810 assert_eq!(elem.attr("inexistent"), None);
811}