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use token::*;
use parse::*;
#[derive(Clone)]
pub struct BEncoded<'a> {
pub data: &'a [u8],
pub depth: i16,
}
impl<'a> BEncoded<'a> {
pub fn new(data: &'a [u8]) -> Self {
BEncoded {
data: data,
depth: 0,
}
}
pub fn empty() -> BEncoded<'static> {
BEncoded {
data: b"",
depth: 0
}
}
}
impl<'a> Iterator for BEncoded<'a> {
type Item = Token<'a>;
fn next(&mut self) -> Option<Self::Item> {
if self.depth < 0 {
return None;
}
match parse_token(self.data) {
None => None,
Some((token, rest)) => {
match token {
Token::ListStart | Token::DictStart =>
self.depth += 1,
Token::End =>
self.depth -= 1,
_ =>
()
}
if self.depth == 0 {
self.depth -= 1;
}
self.data = rest;
Some(token)
}
}
}
}
#[cfg(test)]
mod tests {
fn expect<'a>(input: &'a [u8], expected: &[::Token<'a>]) {
let bencoded = ::BEncoded::new(input);
let result = bencoded.collect::<Vec<::Token<'a>>>();
assert_eq!(result, expected);
}
#[test]
fn test_strings() {
expect(b"4:spam", &[::Token::ByteString(b"spam")]);
}
#[test]
fn test_integers() {
expect(b"i3e", &[::Token::Integer(b"3")]);
expect(b"i-3e", &[::Token::Integer(b"-3")]);
expect(b"i0e", &[::Token::Integer(b"0")]);
}
#[test]
fn test_lists() {
expect(b"l4:spam4:eggse",
&[::Token::ListStart,
::Token::ByteString(b"spam"),
::Token::ByteString(b"eggs"),
::Token::End]);
}
#[test]
fn test_dict() {
expect(b"d3:cow3:moo4:spam4:eggse",
&[::Token::DictStart,
::Token::ByteString(b"cow"),
::Token::ByteString(b"moo"),
::Token::ByteString(b"spam"),
::Token::ByteString(b"eggs"),
::Token::End]);
expect(b"d4:spaml1:a1:bee",
&[::Token::DictStart,
::Token::ByteString(b"spam"),
::Token::ListStart,
::Token::ByteString(b"a"),
::Token::ByteString(b"b"),
::Token::End,
::Token::End]);
}
#[test]
fn test_only_one() {
expect(b"4:spam4:eggs", &[::Token::ByteString(b"spam")]);
}
}