forked from tafia/quick-xml
/
attributes.rs
2247 lines (2033 loc) · 77.9 KB
/
attributes.rs
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//! Xml Attributes module
//!
//! Provides an iterator over attributes key/value pairs
use crate::errors::{Error, Result as XmlResult};
use crate::escape::{do_unescape, escape};
use crate::name::QName;
use crate::reader::{is_whitespace, Reader};
use crate::utils::{write_byte_string, write_cow_string, Bytes};
use std::fmt::{self, Debug, Display, Formatter};
use std::iter::FusedIterator;
use std::{borrow::Cow, collections::HashMap, ops::Range};
/// A struct representing a key/value XML attribute.
///
/// Field `value` stores raw bytes, possibly containing escape-sequences. Most users will likely
/// want to access the value using one of the [`unescaped_value`] and [`unescape_and_decode_value`]
/// functions.
///
/// [`unescaped_value`]: Self::unescaped_value
/// [`unescape_and_decode_value`]: Self::unescape_and_decode_value
#[derive(Clone, PartialEq)]
pub struct Attribute<'a> {
/// The key to uniquely define the attribute.
///
/// If [`Attributes::with_checks`] is turned off, the key might not be unique.
pub key: QName<'a>,
/// The raw value of the attribute.
pub value: Cow<'a, [u8]>,
}
impl<'a> Attribute<'a> {
/// Returns the unescaped value.
///
/// This is normally the value you are interested in. Escape sequences such as `>` are
/// replaced with their unescaped equivalents such as `>`.
///
/// This will allocate if the value contains any escape sequences.
///
/// See also [`unescaped_value_with_custom_entities()`](Self::unescaped_value_with_custom_entities)
pub fn unescaped_value(&self) -> XmlResult<Cow<[u8]>> {
self.make_unescaped_value(None)
}
/// Returns the unescaped value, using custom entities.
///
/// This is normally the value you are interested in. Escape sequences such as `>` are
/// replaced with their unescaped equivalents such as `>`.
/// Additional entities can be provided in `custom_entities`.
///
/// This will allocate if the value contains any escape sequences.
///
/// See also [`unescaped_value()`](Self::unescaped_value)
///
/// # Pre-condition
///
/// The keys and values of `custom_entities`, if any, must be valid UTF-8.
pub fn unescaped_value_with_custom_entities(
&self,
custom_entities: &HashMap<Vec<u8>, Vec<u8>>,
) -> XmlResult<Cow<[u8]>> {
self.make_unescaped_value(Some(custom_entities))
}
fn make_unescaped_value(
&self,
custom_entities: Option<&HashMap<Vec<u8>, Vec<u8>>>,
) -> XmlResult<Cow<[u8]>> {
do_unescape(&*self.value, custom_entities).map_err(Error::EscapeError)
}
/// Decode then unescapes the value
///
/// This allocates a `String` in all cases. For performance reasons it might be a better idea to
/// instead use one of:
///
/// * [`Reader::decoder().decode()`], as it only allocates when the decoding can't be performed otherwise.
/// * [`unescaped_value()`], as it doesn't allocate when no escape sequences are used.
///
/// [`unescaped_value()`]: Self::unescaped_value
/// [`Reader::decoder().decode()`]: crate::reader::Decoder::decode
pub fn unescape_and_decode_value<B>(&self, reader: &Reader<B>) -> XmlResult<String> {
self.do_unescape_and_decode_value(reader, None)
}
/// Decode then unescapes the value with custom entities
///
/// This allocates a `String` in all cases. For performance reasons it might be a better idea to
/// instead use one of:
///
/// * [`Reader::decoder().decode()`], as it only allocates when the decoding can't be performed otherwise.
/// * [`unescaped_value_with_custom_entities()`], as it doesn't allocate when no escape sequences are used.
///
/// [`unescaped_value_with_custom_entities()`]: Self::unescaped_value_with_custom_entities
/// [`Reader::decoder().decode()`]: crate::reader::Decoder::decode
///
/// # Pre-condition
///
/// The keys and values of `custom_entities`, if any, must be valid UTF-8.
pub fn unescape_and_decode_value_with_custom_entities<B>(
&self,
reader: &Reader<B>,
custom_entities: &HashMap<Vec<u8>, Vec<u8>>,
) -> XmlResult<String> {
self.do_unescape_and_decode_value(reader, Some(custom_entities))
}
/// The keys and values of `custom_entities`, if any, must be valid UTF-8.
fn do_unescape_and_decode_value<B>(
&self,
reader: &Reader<B>,
custom_entities: Option<&HashMap<Vec<u8>, Vec<u8>>>,
) -> XmlResult<String> {
let decoded = reader.decoder().decode(&*self.value)?;
let unescaped = do_unescape(decoded.as_bytes(), custom_entities)?;
Ok(String::from_utf8(unescaped.into_owned())?)
}
}
impl<'a> Debug for Attribute<'a> {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
write!(f, "Attribute {{ key: ")?;
write_byte_string(f, self.key.as_ref())?;
write!(f, ", value: ")?;
write_cow_string(f, &self.value)?;
write!(f, " }}")
}
}
impl<'a> From<(&'a [u8], &'a [u8])> for Attribute<'a> {
/// Creates new attribute from raw bytes.
/// Does not apply any transformation to both key and value.
///
/// # Examples
///
/// ```
/// # use pretty_assertions::assert_eq;
/// use quick_xml::events::attributes::Attribute;
///
/// let features = Attribute::from(("features".as_bytes(), "Bells & whistles".as_bytes()));
/// assert_eq!(features.value, "Bells & whistles".as_bytes());
/// ```
fn from(val: (&'a [u8], &'a [u8])) -> Attribute<'a> {
Attribute {
key: QName(val.0),
value: Cow::from(val.1),
}
}
}
impl<'a> From<(&'a str, &'a str)> for Attribute<'a> {
/// Creates new attribute from text representation.
/// Key is stored as-is, but the value will be escaped.
///
/// # Examples
///
/// ```
/// # use pretty_assertions::assert_eq;
/// use quick_xml::events::attributes::Attribute;
///
/// let features = Attribute::from(("features", "Bells & whistles"));
/// assert_eq!(features.value, "Bells & whistles".as_bytes());
/// ```
fn from(val: (&'a str, &'a str)) -> Attribute<'a> {
Attribute {
key: QName(val.0.as_bytes()),
value: escape(val.1.as_bytes()),
}
}
}
impl<'a> From<Attr<&'a [u8]>> for Attribute<'a> {
#[inline]
fn from(attr: Attr<&'a [u8]>) -> Self {
Self {
key: attr.key(),
value: Cow::Borrowed(attr.value()),
}
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////
/// Iterator over XML attributes.
///
/// Yields `Result<Attribute>`. An `Err` will be yielded if an attribute is malformed or duplicated.
/// The duplicate check can be turned off by calling [`with_checks(false)`].
///
/// [`with_checks(false)`]: Self::with_checks
#[derive(Clone, Debug)]
pub struct Attributes<'a> {
/// slice of `Element` corresponding to attributes
bytes: &'a [u8],
/// Iterator state, independent from the actual source of bytes
state: IterState,
}
impl<'a> Attributes<'a> {
/// Creates a new attribute iterator from a buffer.
pub fn new(buf: &'a [u8], pos: usize) -> Self {
Self {
bytes: buf,
state: IterState::new(pos, false),
}
}
/// Creates a new attribute iterator from a buffer, allowing HTML attribute syntax.
pub fn html(buf: &'a [u8], pos: usize) -> Self {
Self {
bytes: buf,
state: IterState::new(pos, true),
}
}
/// Changes whether attributes should be checked for uniqueness.
///
/// The XML specification requires attribute keys in the same element to be unique. This check
/// can be disabled to improve performance slightly.
///
/// (`true` by default)
pub fn with_checks(&mut self, val: bool) -> &mut Attributes<'a> {
self.state.check_duplicates = val;
self
}
}
impl<'a> Iterator for Attributes<'a> {
type Item = Result<Attribute<'a>, AttrError>;
#[inline]
fn next(&mut self) -> Option<Self::Item> {
match self.state.next(self.bytes) {
None => None,
Some(Ok(a)) => Some(Ok(a.map(|range| &self.bytes[range]).into())),
Some(Err(e)) => Some(Err(e)),
}
}
}
impl<'a> FusedIterator for Attributes<'a> {}
////////////////////////////////////////////////////////////////////////////////////////////////////
/// Errors that can be raised during parsing attributes.
///
/// Recovery position in examples shows the position from which parsing of the
/// next attribute will be attempted.
#[derive(Debug, PartialEq)]
pub enum AttrError {
/// Attribute key was not followed by `=`, position relative to the start of
/// the owning tag is provided.
///
/// Example of input that raises this error:
///
/// ```xml
/// <tag key another="attribute"/>
/// <!-- ^~~ error position, recovery position (8) -->
/// ```
///
/// This error can be raised only when the iterator is in XML mode.
ExpectedEq(usize),
/// Attribute value was not found after `=`, position relative to the start
/// of the owning tag is provided.
///
/// Example of input that raises this error:
///
/// ```xml
/// <tag key = />
/// <!-- ^~~ error position, recovery position (10) -->
/// ```
///
/// This error can be returned only for the last attribute in the list,
/// because otherwise any content after `=` will be threated as a value.
/// The XML
///
/// ```xml
/// <tag key = another-key = "value"/>
/// <!-- ^ ^- recovery position (24) -->
/// <!-- '~~ error position (22) -->
/// ```
///
/// will be treated as `Attribute { key = b"key", value = b"another-key" }`
/// and or [`Attribute`] is returned, or [`AttrError::UnquotedValue`] is raised,
/// depending on the parsing mode.
ExpectedValue(usize),
/// Attribute value is not quoted, position relative to the start of the
/// owning tag is provided.
///
/// Example of input that raises this error:
///
/// ```xml
/// <tag key = value />
/// <!-- ^ ^~~ recovery position (15) -->
/// <!-- '~~ error position (10) -->
/// ```
///
/// This error can be raised only when the iterator is in XML mode.
UnquotedValue(usize),
/// Attribute value was not finished with a matching quote, position relative
/// to the start of owning tag and a quote is provided. That position is always
/// a last character in the tag content.
///
/// Example of input that raises this error:
///
/// ```xml
/// <tag key = "value />
/// <tag key = 'value />
/// <!-- ^~~ error position, recovery position (18) -->
/// ```
///
/// This error can be returned only for the last attribute in the list,
/// because all input was consumed during scanning for a quote.
ExpectedQuote(usize, u8),
/// An attribute with the same name was already encountered. Two parameters
/// define (1) the error position relative to the start of the owning tag
/// for a new attribute and (2) the start position of a previously encountered
/// attribute with the same name.
///
/// Example of input that raises this error:
///
/// ```xml
/// <tag key = 'value' key="value2" attr3='value3' />
/// <!-- ^ ^ ^~~ recovery position (32) -->
/// <!-- | '~~ error position (19) -->
/// <!-- '~~ previous position (4) -->
/// ```
///
/// This error is returned only when [`Attributes::with_checks()`] is set
/// to `true` (that is default behavior).
Duplicated(usize, usize),
}
impl Display for AttrError {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
match self {
Self::ExpectedEq(pos) => write!(
f,
r#"position {}: attribute key must be directly followed by `=` or space"#,
pos
),
Self::ExpectedValue(pos) => write!(
f,
r#"position {}: `=` must be followed by an attribute value"#,
pos
),
Self::UnquotedValue(pos) => write!(
f,
r#"position {}: attribute value must be enclosed in `"` or `'`"#,
pos
),
Self::ExpectedQuote(pos, quote) => write!(
f,
r#"position {}: missing closing quote `{}` in attribute value"#,
pos, *quote as char
),
Self::Duplicated(pos1, pos2) => write!(
f,
r#"position {}: duplicated attribute, previous declaration at position {}"#,
pos1, pos2
),
}
}
}
impl std::error::Error for AttrError {}
////////////////////////////////////////////////////////////////////////////////////////////////////
/// A struct representing a key/value XML or HTML [attribute].
///
/// [attribute]: https://www.w3.org/TR/xml11/#NT-Attribute
#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum Attr<T> {
/// Attribute with value enclosed in double quotes (`"`). Attribute key and
/// value provided. This is a canonical XML-style attribute.
DoubleQ(T, T),
/// Attribute with value enclosed in single quotes (`'`). Attribute key and
/// value provided. This is an XML-style attribute.
SingleQ(T, T),
/// Attribute with value not enclosed in quotes. Attribute key and value
/// provided. This is HTML-style attribute, it can be returned in HTML-mode
/// parsing only. In an XML mode [`AttrError::UnquotedValue`] will be raised
/// instead.
///
/// Attribute value can be invalid according to the [HTML specification],
/// in particular, it can contain `"`, `'`, `=`, `<`, and <code>`</code>
/// characters. The absence of the `>` character is nevertheless guaranteed,
/// since the parser extracts [events] based on them even before the start
/// of parsing attributes.
///
/// [HTML specification]: https://html.spec.whatwg.org/#unquoted
/// [events]: crate::events::Event::Start
Unquoted(T, T),
/// Attribute without value. Attribute key provided. This is HTML-style attribute,
/// it can be returned in HTML-mode parsing only. In XML mode
/// [`AttrError::ExpectedEq`] will be raised instead.
Empty(T),
}
impl<T> Attr<T> {
/// Maps an `Attr<T>` to `Attr<U>` by applying a function to a contained key and value.
#[inline]
pub fn map<U, F>(self, mut f: F) -> Attr<U>
where
F: FnMut(T) -> U,
{
match self {
Attr::DoubleQ(key, value) => Attr::DoubleQ(f(key), f(value)),
Attr::SingleQ(key, value) => Attr::SingleQ(f(key), f(value)),
Attr::Empty(key) => Attr::Empty(f(key)),
Attr::Unquoted(key, value) => Attr::Unquoted(f(key), f(value)),
}
}
}
impl<'a> Attr<&'a [u8]> {
/// Returns the key value
#[inline]
pub fn key(&self) -> QName<'a> {
QName(match self {
Attr::DoubleQ(key, _) => key,
Attr::SingleQ(key, _) => key,
Attr::Empty(key) => key,
Attr::Unquoted(key, _) => key,
})
}
/// Returns the attribute value. For [`Self::Empty`] variant an empty slice
/// is returned according to the [HTML specification].
///
/// [HTML specification]: https://www.w3.org/TR/2012/WD-html-markup-20120329/syntax.html#syntax-attr-empty
#[inline]
pub fn value(&self) -> &'a [u8] {
match self {
Attr::DoubleQ(_, value) => value,
Attr::SingleQ(_, value) => value,
Attr::Empty(_) => &[],
Attr::Unquoted(_, value) => value,
}
}
}
impl<T: AsRef<[u8]>> Debug for Attr<T> {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
match self {
Attr::DoubleQ(key, value) => f
.debug_tuple("Attr::DoubleQ")
.field(&Bytes(key.as_ref()))
.field(&Bytes(value.as_ref()))
.finish(),
Attr::SingleQ(key, value) => f
.debug_tuple("Attr::SingleQ")
.field(&Bytes(key.as_ref()))
.field(&Bytes(value.as_ref()))
.finish(),
Attr::Empty(key) => f
.debug_tuple("Attr::Empty")
// Comment to prevent formatting and keep style consistent
.field(&Bytes(key.as_ref()))
.finish(),
Attr::Unquoted(key, value) => f
.debug_tuple("Attr::Unquoted")
.field(&Bytes(key.as_ref()))
.field(&Bytes(value.as_ref()))
.finish(),
}
}
}
/// Unpacks attribute key and value into tuple of this two elements.
/// `None` value element is returned only for [`Attr::Empty`] variant.
impl<T> From<Attr<T>> for (T, Option<T>) {
#[inline]
fn from(attr: Attr<T>) -> Self {
match attr {
Attr::DoubleQ(key, value) => (key, Some(value)),
Attr::SingleQ(key, value) => (key, Some(value)),
Attr::Empty(key) => (key, None),
Attr::Unquoted(key, value) => (key, Some(value)),
}
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////
type AttrResult = Result<Attr<Range<usize>>, AttrError>;
#[derive(Clone, Copy, Debug)]
enum State {
/// Iteration finished, iterator will return `None` to all [`IterState::next`]
/// requests.
Done,
/// The last attribute returned was deserialized successfully. Contains an
/// offset from which next attribute should be searched.
Next(usize),
/// The last attribute returns [`AttrError::UnquotedValue`], offset pointed
/// to the beginning of the value. Recover should skip a value
SkipValue(usize),
/// The last attribute returns [`AttrError::Duplicated`], offset pointed to
/// the equal (`=`) sign. Recover should skip it and a value
SkipEqValue(usize),
}
/// External iterator over spans of attribute key and value
#[derive(Clone, Debug)]
pub(crate) struct IterState {
/// Iteration state that determines what actions should be done before the
/// actual parsing of the next attribute
state: State,
/// If `true`, enables ability to parse unquoted values and key-only (empty)
/// attributes
html: bool,
/// If `true`, checks for duplicate names
check_duplicates: bool,
/// If `check_duplicates` is set, contains the ranges of already parsed attribute
/// names. We store a ranges instead of slices to able to report a previous
/// attribute position
keys: Vec<Range<usize>>,
}
impl IterState {
pub fn new(offset: usize, html: bool) -> Self {
Self {
state: State::Next(offset),
html,
check_duplicates: true,
keys: Vec::new(),
}
}
/// Recover from an error that could have been made on a previous step.
/// Returns an offset from which parsing should continue.
/// If there no input left, returns `None`.
fn recover(&self, slice: &[u8]) -> Option<usize> {
match self.state {
State::Done => None,
State::Next(offset) => Some(offset),
State::SkipValue(offset) => self.skip_value(slice, offset),
State::SkipEqValue(offset) => self.skip_eq_value(slice, offset),
}
}
/// Skip all characters up to first space symbol or end-of-input
#[inline]
fn skip_value(&self, slice: &[u8], offset: usize) -> Option<usize> {
let mut iter = (offset..).zip(slice[offset..].iter());
match iter.find(|(_, &b)| is_whitespace(b)) {
// Input: ` key = value `
// | ^
// offset e
Some((e, _)) => Some(e),
// Input: ` key = value`
// | ^
// offset e = len()
None => None,
}
}
/// Skip all characters up to first space symbol or end-of-input
#[inline]
fn skip_eq_value(&self, slice: &[u8], offset: usize) -> Option<usize> {
let mut iter = (offset..).zip(slice[offset..].iter());
// Skip all up to the quote and get the quote type
let quote = match iter.find(|(_, &b)| !is_whitespace(b)) {
// Input: ` key = "`
// | ^
// offset
Some((_, b'"')) => b'"',
// Input: ` key = '`
// | ^
// offset
Some((_, b'\'')) => b'\'',
// Input: ` key = x`
// | ^
// offset
Some((offset, _)) => return self.skip_value(slice, offset),
// Input: ` key = `
// | ^
// offset
None => return None,
};
match iter.find(|(_, &b)| b == quote) {
// Input: ` key = " "`
// ^
Some((e, b'"')) => Some(e),
// Input: ` key = ' '`
// ^
Some((e, _)) => Some(e),
// Input: ` key = " `
// Input: ` key = ' `
// ^
// Closing quote not found
None => None,
}
}
#[inline]
fn check_for_duplicates(
&mut self,
slice: &[u8],
key: Range<usize>,
) -> Result<Range<usize>, AttrError> {
if self.check_duplicates {
if let Some(prev) = self
.keys
.iter()
.find(|r| slice[(*r).clone()] == slice[key.clone()])
{
return Err(AttrError::Duplicated(key.start, prev.start));
}
self.keys.push(key.clone());
}
Ok(key)
}
/// # Parameters
///
/// - `slice`: content of the tag, used for checking for duplicates
/// - `key`: Range of key in slice, if iterator in HTML mode
/// - `offset`: Position of error if iterator in XML mode
#[inline]
fn key_only(&mut self, slice: &[u8], key: Range<usize>, offset: usize) -> Option<AttrResult> {
Some(if self.html {
self.check_for_duplicates(slice, key).map(Attr::Empty)
} else {
Err(AttrError::ExpectedEq(offset))
})
}
#[inline]
fn double_q(&mut self, key: Range<usize>, value: Range<usize>) -> Option<AttrResult> {
self.state = State::Next(value.end + 1); // +1 for `"`
Some(Ok(Attr::DoubleQ(key, value)))
}
#[inline]
fn single_q(&mut self, key: Range<usize>, value: Range<usize>) -> Option<AttrResult> {
self.state = State::Next(value.end + 1); // +1 for `'`
Some(Ok(Attr::SingleQ(key, value)))
}
pub fn next(&mut self, slice: &[u8]) -> Option<AttrResult> {
let mut iter = match self.recover(slice) {
Some(offset) => (offset..).zip(slice[offset..].iter()),
None => return None,
};
// Index where next key started
let start_key = match iter.find(|(_, &b)| !is_whitespace(b)) {
// Input: ` key`
// ^
Some((s, _)) => s,
// Input: ` `
// ^
None => {
// Because we reach end-of-input, stop iteration on next call
self.state = State::Done;
return None;
}
};
// Span of a key
let (key, offset) = match iter.find(|(_, &b)| b == b'=' || is_whitespace(b)) {
// Input: ` key=`
// | ^
// s e
Some((e, b'=')) => (start_key..e, e),
// Input: ` key `
// ^
Some((e, _)) => match iter.find(|(_, &b)| !is_whitespace(b)) {
// Input: ` key =`
// | | ^
// start_key e
Some((offset, b'=')) => (start_key..e, offset),
// Input: ` key x`
// | | ^
// start_key e
// If HTML-like attributes is allowed, this is the result, otherwise error
Some((offset, _)) => {
// In any case, recovering is not required
self.state = State::Next(offset);
return self.key_only(slice, start_key..e, offset);
}
// Input: ` key `
// | | ^
// start_key e
// If HTML-like attributes is allowed, this is the result, otherwise error
None => {
// Because we reach end-of-input, stop iteration on next call
self.state = State::Done;
return self.key_only(slice, start_key..e, slice.len());
}
},
// Input: ` key`
// | ^
// s e = len()
// If HTML-like attributes is allowed, this is the result, otherwise error
None => {
// Because we reach end-of-input, stop iteration on next call
self.state = State::Done;
let e = slice.len();
return self.key_only(slice, start_key..e, e);
}
};
let key = match self.check_for_duplicates(slice, key) {
Err(e) => {
self.state = State::SkipEqValue(offset);
return Some(Err(e));
}
Ok(key) => key,
};
////////////////////////////////////////////////////////////////////////
// Gets the position of quote and quote type
let (start_value, quote) = match iter.find(|(_, &b)| !is_whitespace(b)) {
// Input: ` key = "`
// ^
Some((s, b'"')) => (s + 1, b'"'),
// Input: ` key = '`
// ^
Some((s, b'\'')) => (s + 1, b'\''),
// Input: ` key = x`
// ^
// If HTML-like attributes is allowed, this is the start of the value
Some((s, _)) if self.html => {
// We do not check validity of attribute value characters as required
// according to https://html.spec.whatwg.org/#unquoted. It can be done
// during validation phase
let end = match iter.find(|(_, &b)| is_whitespace(b)) {
// Input: ` key = value `
// | ^
// s e
Some((e, _)) => e,
// Input: ` key = value`
// | ^
// s e = len()
None => slice.len(),
};
self.state = State::Next(end);
return Some(Ok(Attr::Unquoted(key, s..end)));
}
// Input: ` key = x`
// ^
Some((s, _)) => {
self.state = State::SkipValue(s);
return Some(Err(AttrError::UnquotedValue(s)));
}
// Input: ` key = `
// ^
None => {
// Because we reach end-of-input, stop iteration on next call
self.state = State::Done;
return Some(Err(AttrError::ExpectedValue(slice.len())));
}
};
match iter.find(|(_, &b)| b == quote) {
// Input: ` key = " "`
// ^
Some((e, b'"')) => self.double_q(key, start_value..e),
// Input: ` key = ' '`
// ^
Some((e, _)) => self.single_q(key, start_value..e),
// Input: ` key = " `
// Input: ` key = ' `
// ^
// Closing quote not found
None => {
// Because we reach end-of-input, stop iteration on next call
self.state = State::Done;
return Some(Err(AttrError::ExpectedQuote(slice.len(), quote)));
}
}
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////
/// Checks, how parsing of XML-style attributes works. Each attribute should
/// have a value, enclosed in single or double quotes.
#[cfg(test)]
mod xml {
use super::*;
use pretty_assertions::assert_eq;
/// Checked attribute is the single attribute
mod single {
use super::*;
use pretty_assertions::assert_eq;
/// Attribute have a value enclosed in single quotes
#[test]
fn single_quoted() {
let mut iter = Attributes::new(br#"tag key='value'"#, 3);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"key"),
value: Cow::Borrowed(b"value"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Attribute have a value enclosed in double quotes
#[test]
fn double_quoted() {
let mut iter = Attributes::new(br#"tag key="value""#, 3);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"key"),
value: Cow::Borrowed(b"value"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Attribute have a value, not enclosed in quotes
#[test]
fn unquoted() {
let mut iter = Attributes::new(br#"tag key=value"#, 3);
// 0 ^ = 8
assert_eq!(iter.next(), Some(Err(AttrError::UnquotedValue(8))));
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Only attribute key is present
#[test]
fn key_only() {
let mut iter = Attributes::new(br#"tag key"#, 3);
// 0 ^ = 7
assert_eq!(iter.next(), Some(Err(AttrError::ExpectedEq(7))));
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Key is started with an invalid symbol (a single quote in this test).
/// Because we do not check validity of keys and values during parsing,
/// that invalid attribute will be returned
#[test]
fn key_start_invalid() {
let mut iter = Attributes::new(br#"tag 'key'='value'"#, 3);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"'key'"),
value: Cow::Borrowed(b"value"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Key contains an invalid symbol (an ampersand in this test).
/// Because we do not check validity of keys and values during parsing,
/// that invalid attribute will be returned
#[test]
fn key_contains_invalid() {
let mut iter = Attributes::new(br#"tag key&jey='value'"#, 3);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"key&jey"),
value: Cow::Borrowed(b"value"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Attribute value is missing after `=`
#[test]
fn missed_value() {
let mut iter = Attributes::new(br#"tag key="#, 3);
// 0 ^ = 8
assert_eq!(iter.next(), Some(Err(AttrError::ExpectedValue(8))));
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
}
/// Checked attribute is the first attribute in the list of many attributes
mod first {
use super::*;
use pretty_assertions::assert_eq;
/// Attribute have a value enclosed in single quotes
#[test]
fn single_quoted() {
let mut iter = Attributes::new(br#"tag key='value' regular='attribute'"#, 3);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"key"),
value: Cow::Borrowed(b"value"),
}))
);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"regular"),
value: Cow::Borrowed(b"attribute"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Attribute have a value enclosed in double quotes
#[test]
fn double_quoted() {
let mut iter = Attributes::new(br#"tag key="value" regular='attribute'"#, 3);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"key"),
value: Cow::Borrowed(b"value"),
}))
);
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"regular"),
value: Cow::Borrowed(b"attribute"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Attribute have a value, not enclosed in quotes
#[test]
fn unquoted() {
let mut iter = Attributes::new(br#"tag key=value regular='attribute'"#, 3);
// 0 ^ = 8
assert_eq!(iter.next(), Some(Err(AttrError::UnquotedValue(8))));
// check error recovery
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"regular"),
value: Cow::Borrowed(b"attribute"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Only attribute key is present
#[test]
fn key_only() {
let mut iter = Attributes::new(br#"tag key regular='attribute'"#, 3);
// 0 ^ = 8
assert_eq!(iter.next(), Some(Err(AttrError::ExpectedEq(8))));
// check error recovery
assert_eq!(
iter.next(),
Some(Ok(Attribute {
key: QName(b"regular"),
value: Cow::Borrowed(b"attribute"),
}))
);
assert_eq!(iter.next(), None);
assert_eq!(iter.next(), None);
}
/// Key is started with an invalid symbol (a single quote in this test).
/// Because we do not check validity of keys and values during parsing,
/// that invalid attribute will be returned
#[test]
fn key_start_invalid() {
let mut iter = Attributes::new(br#"tag 'key'='value' regular='attribute'"#, 3);