/// Unicode escape code in byte literal.
UnicodeEscapeInByte,
- /// Non-ascii character in byte literal.
+ /// Non-ascii character in byte literal, byte string literal, or raw byte string literal.
NonAsciiCharInByte,
- /// Non-ascii character in byte string literal.
- NonAsciiCharInByteString,
/// After a line ending with '\', the next line contains whitespace
/// characters that are not skipped.
/// Takes a contents of a literal (without quotes) and produces a
/// sequence of escaped characters or errors.
/// Values are returned through invoking of the provided callback.
-pub fn unescape_literal<F>(literal_text: &str, mode: Mode, callback: &mut F)
+pub fn unescape_literal<F>(src: &str, mode: Mode, callback: &mut F)
where
F: FnMut(Range<usize>, Result<char, EscapeError>),
{
match mode {
Mode::Char | Mode::Byte => {
- let mut chars = literal_text.chars();
- let result = unescape_char_or_byte(&mut chars, mode);
- // The Chars iterator moved forward.
- callback(0..(literal_text.len() - chars.as_str().len()), result);
+ let mut chars = src.chars();
+ let res = unescape_char_or_byte(&mut chars, mode == Mode::Byte);
+ callback(0..(src.len() - chars.as_str().len()), res);
}
- Mode::Str | Mode::ByteStr => unescape_str_or_byte_str(literal_text, mode, callback),
- // NOTE: Raw strings do not perform any explicit character escaping, here we
- // only translate CRLF to LF and produce errors on bare CR.
+ Mode::Str | Mode::ByteStr => unescape_str_or_byte_str(src, mode == Mode::ByteStr, callback),
Mode::RawStr | Mode::RawByteStr => {
- unescape_raw_str_or_raw_byte_str(literal_text, mode, callback)
+ unescape_raw_str_or_raw_byte_str(src, mode == Mode::RawByteStr, callback)
}
}
}
-/// Takes a contents of a byte, byte string or raw byte string (without quotes)
-/// and produces a sequence of bytes or errors.
-/// Values are returned through invoking of the provided callback.
-pub fn unescape_byte_literal<F>(literal_text: &str, mode: Mode, callback: &mut F)
-where
- F: FnMut(Range<usize>, Result<u8, EscapeError>),
-{
- debug_assert!(mode.is_bytes());
- unescape_literal(literal_text, mode, &mut |range, result| {
- callback(range, result.map(byte_from_char));
- })
-}
-
/// Takes a contents of a char literal (without quotes), and returns an
-/// unescaped char or an error
-pub fn unescape_char(literal_text: &str) -> Result<char, (usize, EscapeError)> {
- let mut chars = literal_text.chars();
- unescape_char_or_byte(&mut chars, Mode::Char)
- .map_err(|err| (literal_text.len() - chars.as_str().len(), err))
+/// unescaped char or an error.
+pub fn unescape_char(src: &str) -> Result<char, EscapeError> {
+ unescape_char_or_byte(&mut src.chars(), false)
}
/// Takes a contents of a byte literal (without quotes), and returns an
/// unescaped byte or an error.
-pub fn unescape_byte(literal_text: &str) -> Result<u8, (usize, EscapeError)> {
- let mut chars = literal_text.chars();
- unescape_char_or_byte(&mut chars, Mode::Byte)
- .map(byte_from_char)
- .map_err(|err| (literal_text.len() - chars.as_str().len(), err))
+pub fn unescape_byte(src: &str) -> Result<u8, EscapeError> {
+ unescape_char_or_byte(&mut src.chars(), true).map(byte_from_char)
}
/// What kind of literal do we parse.
}
}
- pub fn is_bytes(self) -> bool {
+ pub fn is_byte(self) -> bool {
match self {
Mode::Byte | Mode::ByteStr | Mode::RawByteStr => true,
Mode::Char | Mode::Str | Mode::RawStr => false,
}
}
-fn scan_escape(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
+fn scan_escape(chars: &mut Chars<'_>, is_byte: bool) -> Result<char, EscapeError> {
// Previous character was '\\', unescape what follows.
-
- let second_char = chars.next().ok_or(EscapeError::LoneSlash)?;
-
- let res = match second_char {
+ let res = match chars.next().ok_or(EscapeError::LoneSlash)? {
'"' => '"',
'n' => '\n',
'r' => '\r',
let value = hi * 16 + lo;
// For a non-byte literal verify that it is within ASCII range.
- if !mode.is_bytes() && !is_ascii(value) {
+ if !is_byte && !is_ascii(value) {
return Err(EscapeError::OutOfRangeHexEscape);
}
let value = value as u8;
// Incorrect syntax has higher priority for error reporting
// than unallowed value for a literal.
- if mode.is_bytes() {
+ if is_byte {
return Err(EscapeError::UnicodeEscapeInByte);
}
}
#[inline]
-fn ascii_check(first_char: char, mode: Mode) -> Result<char, EscapeError> {
- if mode.is_bytes() && !first_char.is_ascii() {
+fn ascii_check(c: char, is_byte: bool) -> Result<char, EscapeError> {
+ if is_byte && !c.is_ascii() {
// Byte literal can't be a non-ascii character.
Err(EscapeError::NonAsciiCharInByte)
} else {
- Ok(first_char)
+ Ok(c)
}
}
-fn unescape_char_or_byte(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
- debug_assert!(mode == Mode::Char || mode == Mode::Byte);
- let first_char = chars.next().ok_or(EscapeError::ZeroChars)?;
- let res = match first_char {
- '\\' => scan_escape(chars, mode),
+fn unescape_char_or_byte(chars: &mut Chars<'_>, is_byte: bool) -> Result<char, EscapeError> {
+ let c = chars.next().ok_or(EscapeError::ZeroChars)?;
+ let res = match c {
+ '\\' => scan_escape(chars, is_byte),
'\n' | '\t' | '\'' => Err(EscapeError::EscapeOnlyChar),
'\r' => Err(EscapeError::BareCarriageReturn),
- _ => ascii_check(first_char, mode),
+ _ => ascii_check(c, is_byte),
}?;
if chars.next().is_some() {
return Err(EscapeError::MoreThanOneChar);
/// Takes a contents of a string literal (without quotes) and produces a
/// sequence of escaped characters or errors.
-fn unescape_str_or_byte_str<F>(src: &str, mode: Mode, callback: &mut F)
+fn unescape_str_or_byte_str<F>(src: &str, is_byte: bool, callback: &mut F)
where
F: FnMut(Range<usize>, Result<char, EscapeError>),
{
- debug_assert!(mode == Mode::Str || mode == Mode::ByteStr);
- let initial_len = src.len();
let mut chars = src.chars();
- while let Some(first_char) = chars.next() {
- let start = initial_len - chars.as_str().len() - first_char.len_utf8();
- let unescaped_char = match first_char {
+ // The `start` and `end` computation here is complicated because
+ // `skip_ascii_whitespace` makes us to skip over chars without counting
+ // them in the range computation.
+ while let Some(c) = chars.next() {
+ let start = src.len() - chars.as_str().len() - c.len_utf8();
+ let res = match c {
'\\' => {
- let second_char = chars.clone().next();
- match second_char {
+ match chars.clone().next() {
Some('\n') => {
// Rust language specification requires us to skip whitespaces
// if unescaped '\' character is followed by '\n'.
skip_ascii_whitespace(&mut chars, start, callback);
continue;
}
- _ => scan_escape(&mut chars, mode),
+ _ => scan_escape(&mut chars, is_byte),
}
}
'\n' => Ok('\n'),
'\t' => Ok('\t'),
'"' => Err(EscapeError::EscapeOnlyChar),
'\r' => Err(EscapeError::BareCarriageReturn),
- _ => ascii_check(first_char, mode),
+ _ => ascii_check(c, is_byte),
};
- let end = initial_len - chars.as_str().len();
- callback(start..end, unescaped_char);
+ let end = src.len() - chars.as_str().len();
+ callback(start..end, res);
}
fn skip_ascii_whitespace<F>(chars: &mut Chars<'_>, start: usize, callback: &mut F)
/// Takes a contents of a string literal (without quotes) and produces a
/// sequence of characters or errors.
/// NOTE: Raw strings do not perform any explicit character escaping, here we
-/// only translate CRLF to LF and produce errors on bare CR.
-fn unescape_raw_str_or_raw_byte_str<F>(literal_text: &str, mode: Mode, callback: &mut F)
+/// only produce errors on bare CR.
+fn unescape_raw_str_or_raw_byte_str<F>(src: &str, is_byte: bool, callback: &mut F)
where
F: FnMut(Range<usize>, Result<char, EscapeError>),
{
- debug_assert!(mode == Mode::RawStr || mode == Mode::RawByteStr);
- let initial_len = literal_text.len();
-
- let mut chars = literal_text.chars();
- while let Some(curr) = chars.next() {
- let start = initial_len - chars.as_str().len() - curr.len_utf8();
+ let mut chars = src.chars();
- let result = match curr {
+ // The `start` and `end` computation here matches the one in
+ // `unescape_str_or_byte_str` for consistency, even though this function
+ // doesn't have to worry about skipping any chars.
+ while let Some(c) = chars.next() {
+ let start = src.len() - chars.as_str().len() - c.len_utf8();
+ let res = match c {
'\r' => Err(EscapeError::BareCarriageReturnInRawString),
- c if mode.is_bytes() && !c.is_ascii() => Err(EscapeError::NonAsciiCharInByteString),
- c => Ok(c),
+ _ => ascii_check(c, is_byte),
};
- let end = initial_len - chars.as_str().len();
-
- callback(start..end, result);
+ let end = src.len() - chars.as_str().len();
+ callback(start..end, res);
}
}
-fn byte_from_char(c: char) -> u8 {
+#[inline]
+pub fn byte_from_char(c: char) -> u8 {
let res = c as u32;
debug_assert!(res <= u8::MAX as u32, "guaranteed because of Mode::ByteStr");
res as u8
projects / rustc.git / blobdiff