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 let root: Element;
289
290 loop {
291 let e = reader.read_event(&mut buf)?;
292 match e {
293 Event::Empty(ref e) | Event::Start(ref e) => {
294 root = build_element(e)?; // FIXME: could be break build_element(e)? when break value is stable
295 break;
296 },
297 Event::Eof => {
298 bail!(ErrorKind::EndOfDocument);
299 },
300 _ => () // TODO: may need more errors
301 }
302 };
303
304 let mut stack = vec![root];
305
306 loop {
307 match reader.read_event(&mut buf)? {
308 Event::Empty(ref e) => {
309 let elem = build_element(e)?;
310 // Since there is no Event::End after, directly append it to the current node
311 stack.last_mut().unwrap().append_child(elem);
312 },
313 Event::Start(ref e) => {
314 let elem = build_element(e)?;
315 stack.push(elem);
316 },
317 Event::End(ref e) => {
318 if stack.len() <= 1 {
319 break;
320 }
321 let elem = stack.pop().unwrap();
322 if let Some(to) = stack.last_mut() {
323 if elem.name().as_bytes() != e.name() {
324 bail!(ErrorKind::InvalidElementClosed);
325 }
326 to.append_child(elem);
327 }
328 },
329 Event::Text(s) | Event::CData(s) => {
330 let text = s.unescape_and_decode(reader)?;
331 if text != "" {
332 let mut current_elem = stack.last_mut().unwrap();
333 current_elem.append_text_node(text);
334 }
335 },
336 Event::Eof => {
337 break;
338 },
339 _ => (), // TODO: may need to implement more
340 }
341 }
342 Ok(stack.pop().unwrap())
343 }
344
345 /// Output a document to a `Writer`.
346 pub fn write_to<W: Write>(&self, writer: &mut W) -> Result<()> {
347 write!(writer, "<?xml version=\"1.0\" encoding=\"utf-8\"?>")?;
348 self.write_to_inner(writer)
349 }
350
351 /// Like `write_to()` but without the `<?xml?>` prelude
352 pub fn write_to_inner<W: Write>(&self, writer: &mut W) -> Result<()> {
353 let name = match &self.prefix {
354 &None => Cow::Borrowed(&self.name),
355 &Some(ref prefix) => Cow::Owned(format!("{}:{}", prefix, self.name)),
356 };
357 write!(writer, "<{}", name)?;
358
359 for (prefix, ns) in self.namespaces.declared_ns() {
360 match prefix {
361 &None => {
362 write!(writer, " xmlns=\"")?;
363 write_escaped(writer, ns)?;
364 write!(writer, "\"")?;
365 },
366 &Some(ref prefix) => {
367 write!(writer, " xmlns:{}=\"", prefix)?;
368 write_escaped(writer, ns)?;
369 write!(writer, "\"")?;
370 },
371 }
372 }
373
374 for (key, value) in &self.attributes {
375 write!(writer, " {}=\"", key)?;
376 write_escaped(writer, value)?;
377 write!(writer, "\"")?;
378 }
379
380 if self.children.is_empty() {
381 write!(writer, " />")?;
382 return Ok(())
383 }
384
385 write!(writer, ">")?;
386
387 for child in &self.children {
388 child.write_to_inner(writer)?;
389 }
390
391 write!(writer, "</{}>", name)?;
392 Ok(())
393 }
394
395 /// Returns an iterator over references to every child node of this element.
396 ///
397 /// # Examples
398 ///
399 /// ```rust
400 /// use minidom::Element;
401 ///
402 /// let elem: Element = "<root>a<c1 />b<c2 />c</root>".parse().unwrap();
403 ///
404 /// let mut iter = elem.nodes();
405 ///
406 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "a");
407 /// assert_eq!(iter.next().unwrap().as_element().unwrap().name(), "c1");
408 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "b");
409 /// assert_eq!(iter.next().unwrap().as_element().unwrap().name(), "c2");
410 /// assert_eq!(iter.next().unwrap().as_text().unwrap(), "c");
411 /// assert_eq!(iter.next(), None);
412 /// ```
413 #[inline] pub fn nodes(&self) -> Nodes {
414 self.children.iter()
415 }
416
417 /// Returns an iterator over mutable references to every child node of this element.
418 #[inline] pub fn nodes_mut(&mut self) -> NodesMut {
419 self.children.iter_mut()
420 }
421
422 /// Returns an iterator over references to every child element of this element.
423 ///
424 /// # Examples
425 ///
426 /// ```rust
427 /// use minidom::Element;
428 ///
429 /// let elem: Element = "<root>hello<child1 />this<child2 />is<child3 />ignored</root>".parse().unwrap();
430 ///
431 /// let mut iter = elem.children();
432 /// assert_eq!(iter.next().unwrap().name(), "child1");
433 /// assert_eq!(iter.next().unwrap().name(), "child2");
434 /// assert_eq!(iter.next().unwrap().name(), "child3");
435 /// assert_eq!(iter.next(), None);
436 /// ```
437 #[inline] pub fn children(&self) -> Children {
438 Children {
439 iter: self.children.iter(),
440 }
441 }
442
443 /// Returns an iterator over mutable references to every child element of this element.
444 #[inline] pub fn children_mut(&mut self) -> ChildrenMut {
445 ChildrenMut {
446 iter: self.children.iter_mut(),
447 }
448 }
449
450 /// Returns an iterator over references to every text node of this element.
451 ///
452 /// # Examples
453 ///
454 /// ```rust
455 /// use minidom::Element;
456 ///
457 /// let elem: Element = "<root>hello<c /> world!</root>".parse().unwrap();
458 ///
459 /// let mut iter = elem.texts();
460 /// assert_eq!(iter.next().unwrap(), "hello");
461 /// assert_eq!(iter.next().unwrap(), " world!");
462 /// assert_eq!(iter.next(), None);
463 /// ```
464 #[inline] pub fn texts(&self) -> Texts {
465 Texts {
466 iter: self.children.iter(),
467 }
468 }
469
470 /// Returns an iterator over mutable references to every text node of this element.
471 #[inline] pub fn texts_mut(&mut self) -> TextsMut {
472 TextsMut {
473 iter: self.children.iter_mut(),
474 }
475 }
476
477 /// Appends a child node to the `Element`, returning the appended node.
478 ///
479 /// # Examples
480 ///
481 /// ```rust
482 /// use minidom::Element;
483 ///
484 /// let mut elem = Element::bare("root");
485 ///
486 /// assert_eq!(elem.children().count(), 0);
487 ///
488 /// elem.append_child(Element::bare("child"));
489 ///
490 /// {
491 /// let mut iter = elem.children();
492 /// assert_eq!(iter.next().unwrap().name(), "child");
493 /// assert_eq!(iter.next(), None);
494 /// }
495 ///
496 /// let child = elem.append_child(Element::bare("new"));
497 ///
498 /// assert_eq!(child.name(), "new");
499 /// ```
500 pub fn append_child(&mut self, child: Element) -> &mut Element {
501 child.namespaces.set_parent(self.namespaces.clone());
502
503 self.children.push(Node::Element(child));
504 if let Node::Element(ref mut cld) = *self.children.last_mut().unwrap() {
505 cld
506 } else {
507 unreachable!()
508 }
509 }
510
511 /// Appends a text node to an `Element`.
512 ///
513 /// # Examples
514 ///
515 /// ```rust
516 /// use minidom::Element;
517 ///
518 /// let mut elem = Element::bare("node");
519 ///
520 /// assert_eq!(elem.text(), "");
521 ///
522 /// elem.append_text_node("text");
523 ///
524 /// assert_eq!(elem.text(), "text");
525 /// ```
526 pub fn append_text_node<S: Into<String>>(&mut self, child: S) {
527 self.children.push(Node::Text(child.into()));
528 }
529
530 /// Appends a node to an `Element`.
531 ///
532 /// # Examples
533 ///
534 /// ```rust
535 /// use minidom::{Element, Node};
536 ///
537 /// let mut elem = Element::bare("node");
538 ///
539 /// elem.append_node(Node::Text("hello".to_owned()));
540 ///
541 /// assert_eq!(elem.text(), "hello");
542 /// ```
543 pub fn append_node(&mut self, node: Node) {
544 self.children.push(node);
545 }
546
547 /// Returns the concatenation of all text nodes in the `Element`.
548 ///
549 /// # Examples
550 ///
551 /// ```rust
552 /// use minidom::Element;
553 ///
554 /// let elem: Element = "<node>hello,<split /> world!</node>".parse().unwrap();
555 ///
556 /// assert_eq!(elem.text(), "hello, world!");
557 /// ```
558 pub fn text(&self) -> String {
559 self.texts().fold(String::new(), |ret, new| ret + new)
560 }
561
562 /// Returns a reference to the first child element with the specific name and namespace, if it
563 /// exists in the direct descendants of this `Element`, else returns `None`.
564 ///
565 /// # Examples
566 ///
567 /// ```rust
568 /// use minidom::Element;
569 ///
570 /// let elem: Element = r#"<node xmlns="ns"><a /><a xmlns="other_ns" /><b /></node>"#.parse().unwrap();
571 ///
572 /// assert!(elem.get_child("a", "ns").unwrap().is("a", "ns"));
573 /// assert!(elem.get_child("a", "other_ns").unwrap().is("a", "other_ns"));
574 /// assert!(elem.get_child("b", "ns").unwrap().is("b", "ns"));
575 /// assert_eq!(elem.get_child("c", "ns"), None);
576 /// assert_eq!(elem.get_child("b", "other_ns"), None);
577 /// assert_eq!(elem.get_child("a", "inexistent_ns"), None);
578 /// ```
579 pub fn get_child<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> Option<&Element> {
580 for fork in &self.children {
581 if let Node::Element(ref e) = *fork {
582 if e.is(name.as_ref(), namespace.as_ref()) {
583 return Some(e);
584 }
585 }
586 }
587 None
588 }
589
590 /// Returns a mutable reference to the first child element with the specific name and namespace,
591 /// if it exists in the direct descendants of this `Element`, else returns `None`.
592 pub fn get_child_mut<N: AsRef<str>, NS: AsRef<str>>(&mut self, name: N, namespace: NS) -> Option<&mut Element> {
593 for fork in &mut self.children {
594 if let Node::Element(ref mut e) = *fork {
595 if e.is(name.as_ref(), namespace.as_ref()) {
596 return Some(e);
597 }
598 }
599 }
600 None
601 }
602
603 /// Returns whether a specific child with this name and namespace exists in the direct
604 /// descendants of the `Element`.
605 ///
606 /// # Examples
607 ///
608 /// ```rust
609 /// use minidom::Element;
610 ///
611 /// let elem: Element = r#"<node xmlns="ns"><a /><a xmlns="other_ns" /><b /></node>"#.parse().unwrap();
612 ///
613 /// assert_eq!(elem.has_child("a", "other_ns"), true);
614 /// assert_eq!(elem.has_child("a", "ns"), true);
615 /// assert_eq!(elem.has_child("a", "inexistent_ns"), false);
616 /// assert_eq!(elem.has_child("b", "ns"), true);
617 /// assert_eq!(elem.has_child("b", "other_ns"), false);
618 /// assert_eq!(elem.has_child("b", "inexistent_ns"), false);
619 /// ```
620 pub fn has_child<N: AsRef<str>, NS: AsRef<str>>(&self, name: N, namespace: NS) -> bool {
621 self.get_child(name, namespace).is_some()
622 }
623}
624
625fn split_element_name<S: AsRef<str>>(s: S) -> Result<(Option<String>, String)> {
626 let name_parts = s.as_ref().split(':').collect::<Vec<&str>>();
627 match name_parts.len() {
628 2 => Ok((Some(name_parts[0].to_owned()), name_parts[1].to_owned())),
629 1 => Ok((None, name_parts[0].to_owned())),
630 _ => bail!(ErrorKind::InvalidElement),
631 }
632}
633
634fn build_element(event: &BytesStart) -> Result<Element> {
635 let mut namespaces = BTreeMap::new();
636 let attributes = event.attributes()
637 .map(|o| {
638 let o = o?;
639 let key = str::from_utf8(o.key)?.to_owned();
640 let value = str::from_utf8(o.value)?.to_owned();
641 Ok((key, value))
642 })
643 .filter(|o| {
644 match o {
645 &Ok((ref key, ref value)) if key == "xmlns" => {
646 namespaces.insert(None, value.to_owned());
647 false
648 },
649 &Ok((ref key, ref value)) if key.starts_with("xmlns:") => {
650 namespaces.insert(Some(key[6..].to_owned()), value.to_owned());
651 false
652 },
653 _ => true,
654 }
655 })
656 .collect::<Result<BTreeMap<String, String>>>()?;
657
658 let (prefix, name) = split_element_name(str::from_utf8(event.name())?)?;
659 let element = Element::new(name, prefix, namespaces, attributes, Vec::new());
660 Ok(element)
661}
662
663/// An iterator over references to child elements of an `Element`.
664pub struct Children<'a> {
665 iter: slice::Iter<'a, Node>,
666}
667
668impl<'a> Iterator for Children<'a> {
669 type Item = &'a Element;
670
671 fn next(&mut self) -> Option<&'a Element> {
672 for item in &mut self.iter {
673 if let Node::Element(ref child) = *item {
674 return Some(child);
675 }
676 }
677 None
678 }
679}
680
681/// An iterator over mutable references to child elements of an `Element`.
682pub struct ChildrenMut<'a> {
683 iter: slice::IterMut<'a, Node>,
684}
685
686impl<'a> Iterator for ChildrenMut<'a> {
687 type Item = &'a mut Element;
688
689 fn next(&mut self) -> Option<&'a mut Element> {
690 for item in &mut self.iter {
691 if let Node::Element(ref mut child) = *item {
692 return Some(child);
693 }
694 }
695 None
696 }
697}
698
699/// An iterator over references to child text nodes of an `Element`.
700pub struct Texts<'a> {
701 iter: slice::Iter<'a, Node>,
702}
703
704impl<'a> Iterator for Texts<'a> {
705 type Item = &'a str;
706
707 fn next(&mut self) -> Option<&'a str> {
708 for item in &mut self.iter {
709 if let Node::Text(ref child) = *item {
710 return Some(child);
711 }
712 }
713 None
714 }
715}
716
717/// An iterator over mutable references to child text nodes of an `Element`.
718pub struct TextsMut<'a> {
719 iter: slice::IterMut<'a, Node>,
720}
721
722impl<'a> Iterator for TextsMut<'a> {
723 type Item = &'a mut String;
724
725 fn next(&mut self) -> Option<&'a mut String> {
726 for item in &mut self.iter {
727 if let Node::Text(ref mut child) = *item {
728 return Some(child);
729 }
730 }
731 None
732 }
733}
734
735/// An iterator over references to all child nodes of an `Element`.
736pub type Nodes<'a> = slice::Iter<'a, Node>;
737
738/// An iterator over mutable references to all child nodes of an `Element`.
739pub type NodesMut<'a> = slice::IterMut<'a, Node>;
740
741/// An iterator over the attributes of an `Element`.
742pub struct Attrs<'a> {
743 iter: btree_map::Iter<'a, String, String>,
744}
745
746impl<'a> Iterator for Attrs<'a> {
747 type Item = (&'a str, &'a str);
748
749 fn next(&mut self) -> Option<Self::Item> {
750 self.iter.next().map(|(x, y)| (x.as_ref(), y.as_ref()))
751 }
752}
753
754/// An iterator over the attributes of an `Element`, with the values mutable.
755pub struct AttrsMut<'a> {
756 iter: btree_map::IterMut<'a, String, String>,
757}
758
759impl<'a> Iterator for AttrsMut<'a> {
760 type Item = (&'a str, &'a mut String);
761
762 fn next(&mut self) -> Option<Self::Item> {
763 self.iter.next().map(|(x, y)| (x.as_ref(), y))
764 }
765}
766
767/// A builder for `Element`s.
768pub struct ElementBuilder {
769 root: Element,
770 namespaces: BTreeMap<Option<String>, String>,
771}
772
773impl ElementBuilder {
774 /// Sets the namespace.
775 pub fn ns<S: Into<String>>(mut self, namespace: S) -> ElementBuilder {
776 self.namespaces
777 .insert(self.root.prefix.clone(), namespace.into());
778 self
779 }
780
781 /// Sets an attribute.
782 pub fn attr<S: Into<String>, V: IntoAttributeValue>(mut self, name: S, value: V) -> ElementBuilder {
783 self.root.set_attr(name, value);
784 self
785 }
786
787 /// Appends anything implementing `IntoElements` into the tree.
788 pub fn append<T: IntoElements>(mut self, into: T) -> ElementBuilder {
789 {
790 let mut emitter = ElementEmitter::new(&mut self.root);
791 into.into_elements(&mut emitter);
792 }
793 self
794 }
795
796 /// Builds the `Element`.
797 pub fn build(self) -> Element {
798 let mut element = self.root;
799 // Set namespaces
800 element.namespaces = Rc::new(NamespaceSet::from(self.namespaces));
801 // Propagate namespaces
802 for node in &element.children {
803 if let Node::Element(ref e) = *node {
804 e.namespaces.set_parent(element.namespaces.clone());
805 }
806 }
807
808 element
809 }
810}
811
812#[cfg(test)]
813#[test]
814fn test_element_new() {
815 use std::iter::FromIterator;
816
817 let elem = Element::new( "name".to_owned()
818 , None
819 , Some("namespace".to_owned())
820 , BTreeMap::from_iter(vec![ ("name".to_string(), "value".to_string()) ].into_iter() )
821 , Vec::new() );
822
823 assert_eq!(elem.name(), "name");
824 assert_eq!(elem.ns(), Some("namespace".to_owned()));
825 assert_eq!(elem.attr("name"), Some("value"));
826 assert_eq!(elem.attr("inexistent"), None);
827}