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#![no_std]
#![warn(missing_docs)]
#![forbid(unsafe_code)]
mod elements;
pub use elements::*;
mod attributes;
pub use attributes::*;
#[cfg(feature="alloc")]
extern crate alloc;
#[cfg(feature="alloc")]
use alloc::string::String;
#[cfg(feature="alloc")]
pub fn revert_xml_encoding(text: &str) -> String {
let mut out = String::with_capacity(text.as_bytes().len());
let mut chars = text.chars();
while let Some(c) = chars.next() {
if c != '&' {
out.push(c);
} else {
match chars.next().unwrap() {
'l' => {
assert_eq!(chars.next().unwrap(), 't');
assert_eq!(chars.next().unwrap(), ';');
out.push('<');
}
'g' => {
assert_eq!(chars.next().unwrap(), 't');
assert_eq!(chars.next().unwrap(), ';');
out.push('>');
}
'a' => {
assert_eq!(chars.next().unwrap(), 'm');
assert_eq!(chars.next().unwrap(), 'p');
assert_eq!(chars.next().unwrap(), ';');
out.push('&');
}
other => panic!("unknown '&' char: {}", other),
}
}
}
out
}
fn break_on_first_char(input: &str, c: char) -> Option<(&str, &str)> {
input.find(c).map(|b| {
let mut buf = [0_u8; 4];
let utf8_bytes_this_char = c.encode_utf8(&mut buf).len();
let (head, tail) = input.split_at(b);
let tail = &tail[utf8_bytes_this_char..];
(head, tail)
})
}
#[test]
fn test_break_on_first_char() {
assert_eq!(break_on_first_char("", '='), None);
assert_eq!(break_on_first_char("a", '='), None);
assert_eq!(break_on_first_char("a=", '='), Some(("a", "")));
assert_eq!(break_on_first_char("a=b", '='), Some(("a", "b")));
}
fn break_on_first_str<'i>(
input: &'i str,
needle: &str,
) -> Option<(&'i str, &'i str)> {
input.find(needle).map(|b| {
let (head, tail) = input.split_at(b);
let tail = &tail[needle.len()..];
(head, tail)
})
}
#[test]
fn test_break_on_first_str() {
assert_eq!(break_on_first_str("", "=="), None);
assert_eq!(break_on_first_str("a", "=="), None);
assert_eq!(break_on_first_str("a=", "=="), None);
assert_eq!(break_on_first_str("a==", "=="), Some(("a", "")));
assert_eq!(break_on_first_str("a==b", "=="), Some(("a", "b")));
}