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extern crate utf8;
use std::borrow::Cow;
use std::collections::VecDeque;
use std::io;
use utf8::*;
/// A re-implementation of std::str::from_utf8
pub fn str_from_utf8(input: &[u8]) -> Result<&str, usize> {
match decode(input) {
Ok(s) => return Ok(s),
Err(DecodeError::Invalid { valid_prefix, .. }) |
Err(DecodeError::Incomplete { valid_prefix, .. }) => Err(valid_prefix.len()),
}
}
#[test]
fn test_str_from_utf8() {
let xs = b"hello";
assert_eq!(str_from_utf8(xs), Ok("hello"));
let xs = "ศไทย中华Việt Nam".as_bytes();
assert_eq!(str_from_utf8(xs), Ok("ศไทย中华Việt Nam"));
let xs = b"hello\xFF";
assert!(str_from_utf8(xs).is_err());
}
#[test]
fn test_is_utf8() {
// Chars of 1, 2, 3, and 4 bytes
assert!(str_from_utf8("eé€\u{10000}".as_bytes()).is_ok());
// invalid prefix
assert!(str_from_utf8(&[0x80]).is_err());
// invalid 2 byte prefix
assert!(str_from_utf8(&[0xc0]).is_err());
assert!(str_from_utf8(&[0xc0, 0x10]).is_err());
// invalid 3 byte prefix
assert!(str_from_utf8(&[0xe0]).is_err());
assert!(str_from_utf8(&[0xe0, 0x10]).is_err());
assert!(str_from_utf8(&[0xe0, 0xff, 0x10]).is_err());
// invalid 4 byte prefix
assert!(str_from_utf8(&[0xf0]).is_err());
assert!(str_from_utf8(&[0xf0, 0x10]).is_err());
assert!(str_from_utf8(&[0xf0, 0xff, 0x10]).is_err());
assert!(str_from_utf8(&[0xf0, 0xff, 0xff, 0x10]).is_err());
// deny overlong encodings
assert!(str_from_utf8(&[0xc0, 0x80]).is_err());
assert!(str_from_utf8(&[0xc0, 0xae]).is_err());
assert!(str_from_utf8(&[0xe0, 0x80, 0x80]).is_err());
assert!(str_from_utf8(&[0xe0, 0x80, 0xaf]).is_err());
assert!(str_from_utf8(&[0xe0, 0x81, 0x81]).is_err());
assert!(str_from_utf8(&[0xf0, 0x82, 0x82, 0xac]).is_err());
assert!(str_from_utf8(&[0xf4, 0x90, 0x80, 0x80]).is_err());
// deny surrogates
assert!(str_from_utf8(&[0xED, 0xA0, 0x80]).is_err());
assert!(str_from_utf8(&[0xED, 0xBF, 0xBF]).is_err());
assert!(str_from_utf8(&[0xC2, 0x80]).is_ok());
assert!(str_from_utf8(&[0xDF, 0xBF]).is_ok());
assert!(str_from_utf8(&[0xE0, 0xA0, 0x80]).is_ok());
assert!(str_from_utf8(&[0xED, 0x9F, 0xBF]).is_ok());
assert!(str_from_utf8(&[0xEE, 0x80, 0x80]).is_ok());
assert!(str_from_utf8(&[0xEF, 0xBF, 0xBF]).is_ok());
assert!(str_from_utf8(&[0xF0, 0x90, 0x80, 0x80]).is_ok());
assert!(str_from_utf8(&[0xF4, 0x8F, 0xBF, 0xBF]).is_ok());
}
/// A re-implementation of String::from_utf8_lossy
pub fn string_from_utf8_lossy(input: &[u8]) -> Cow<str> {
let mut result = decode(input);
if let Ok(s) = result {
return s.into()
}
let mut string = String::with_capacity(input.len() + REPLACEMENT_CHARACTER.len());
loop {
match result {
Ok(s) => {
string.push_str(s);
return string.into()
}
Err(DecodeError::Incomplete { valid_prefix, .. }) => {
string.push_str(valid_prefix);
string.push_str(REPLACEMENT_CHARACTER);
return string.into()
}
Err(DecodeError::Invalid { valid_prefix, remaining_input, .. }) => {
string.push_str(valid_prefix);
string.push_str(REPLACEMENT_CHARACTER);
result = decode(remaining_input);
}
}
}
}
pub const DECODED_LOSSY: &'static [(&'static [u8], &'static str)] = &[
(b"hello", "hello"),
(b"\xe0\xb8\xa8\xe0\xb9\x84\xe0\xb8\x97\xe0\xb8\xa2\xe4\xb8\xad\xe5\x8d\x8e", "ศไทย中华"),
(b"Vi\xe1\xbb\x87t Nam", "Việt Nam"),
(b"Hello\xC2 There\xFF ", "Hello\u{FFFD} There\u{FFFD} "),
(b"Hello\xC0\x80 There", "Hello\u{FFFD}\u{FFFD} There"),
(b"\xE6\x83 Goodbye", "\u{FFFD} Goodbye"),
(b"\xF5foo\xF5\x80bar", "\u{FFFD}foo\u{FFFD}\u{FFFD}bar"),
(b"\xF5foo\xF5\xC2", "\u{FFFD}foo\u{FFFD}\u{FFFD}"),
(b"\xF1foo\xF1\x80bar\xF1\x80\x80baz", "\u{FFFD}foo\u{FFFD}bar\u{FFFD}baz"),
(b"\xF4foo\xF4\x80bar\xF4\xBFbaz", "\u{FFFD}foo\u{FFFD}bar\u{FFFD}\u{FFFD}baz"),
(b"\xF0\x80\x80\x80foo\xF0\x90\x80\x80bar", "\u{FFFD}\u{FFFD}\u{FFFD}\u{FFFD}foo\u{10000}bar"),
(b"\xF0\x90\x80foo", "\u{FFFD}foo"),
// surrogates
(b"\xED\xA0\x80foo\xED\xBF\xBFbar", "\u{FFFD}\u{FFFD}\u{FFFD}foo\u{FFFD}\u{FFFD}\u{FFFD}bar"),
];
#[test]
fn test_string_from_utf8_lossy() {
for &(input, expected) in DECODED_LOSSY {
assert_eq!(string_from_utf8_lossy(input), expected);
}
}
pub fn all_partitions<'a, F>(input: &'a [u8], f: F)
where F: Fn(&[&[u8]])
{
fn all_partitions_inner<'a, F>(chunks: &mut Vec<&'a [u8]>, input: &'a [u8], f: &F)
where F: Fn(&[&[u8]])
{
if input.is_empty() {
f(chunks)
}
for i in 1..(input.len() + 1) {
chunks.push(&input[..i]);
all_partitions_inner(chunks, &input[i..], f);
chunks.pop();
}
}
let mut chunks = Vec::new();
all_partitions_inner(&mut chunks, input, &f);
assert_eq!(chunks.len(), 0);
}
#[test]
fn test_incremental_decoder() {
for &(input, expected) in DECODED_LOSSY {
all_partitions(input, |chunks| {
let mut string = String::new();
{
let mut decoder = LossyDecoder::new(|s| string.push_str(s));
for &chunk in &*chunks {
decoder.feed(chunk);
}
}
assert_eq!(string, expected);
});
}
}
#[test]
fn test_bufread_decoder() {
for &(input, expected) in DECODED_LOSSY {
all_partitions(input, |chunks| {
let chunks = Chunks(chunks.to_vec().into());
let string = BufReadDecoder::read_to_string_lossy(chunks).unwrap();
assert_eq!(string, expected)
});
}
}
struct Chunks<'a>(VecDeque<&'a [u8]>);
impl<'a> io::Read for Chunks<'a> {
fn read(&mut self, _: &mut [u8]) -> io::Result<usize> {
unimplemented!()
}
}
impl<'a> io::BufRead for Chunks<'a> {
fn fill_buf(&mut self) -> io::Result<&[u8]> {
Ok(*self.0.front().unwrap())
}
fn consume(&mut self, bytes: usize) {
{
let front = self.0.front_mut().unwrap();
*front = &front[bytes..];
if !front.is_empty() {
return
}
}
if self.0.len() > 1 {
self.0.pop_front();
}
}
}
|
