Merge pull request #71 from lifthrasiir/json-split-branch

Replace a redundant `escape` variable with nested matches.
This commit is contained in:
Erick Tryzelaar 2015-05-07 10:51:57 -07:00
commit af752ddcb5

View File

@ -307,89 +307,87 @@ impl<Iter> Deserializer<Iter>
fn parse_string(&mut self) -> Result<(), Error> {
self.str_buf.clear();
let mut escape = false;
loop {
let ch = match try!(self.next_char()) {
Some(ch) => ch,
None => { return Err(self.error(ErrorCode::EOFWhileParsingString)); }
};
if escape {
match ch {
b'"' => self.str_buf.push(b'"'),
b'\\' => self.str_buf.push(b'\\'),
b'/' => self.str_buf.push(b'/'),
b'b' => self.str_buf.push(b'\x08'),
b'f' => self.str_buf.push(b'\x0c'),
b'n' => self.str_buf.push(b'\n'),
b'r' => self.str_buf.push(b'\r'),
b't' => self.str_buf.push(b'\t'),
b'u' => {
let c = match try!(self.decode_hex_escape()) {
0xDC00 ... 0xDFFF => {
return Err(self.error(ErrorCode::LoneLeadingSurrogateInHexEscape));
}
match ch {
b'"' => {
try!(self.bump());
return Ok(());
}
b'\\' => {
let ch = match try!(self.next_char()) {
Some(ch) => ch,
None => { return Err(self.error(ErrorCode::EOFWhileParsingString)); }
};
// Non-BMP characters are encoded as a sequence of
// two hex escapes, representing UTF-16 surrogates.
n1 @ 0xD800 ... 0xDBFF => {
match (try!(self.next_char()), try!(self.next_char())) {
(Some(b'\\'), Some(b'u')) => (),
_ => {
return Err(self.error(ErrorCode::UnexpectedEndOfHexEscape));
}
}
let n2 = try!(self.decode_hex_escape());
if n2 < 0xDC00 || n2 > 0xDFFF {
match ch {
b'"' => self.str_buf.push(b'"'),
b'\\' => self.str_buf.push(b'\\'),
b'/' => self.str_buf.push(b'/'),
b'b' => self.str_buf.push(b'\x08'),
b'f' => self.str_buf.push(b'\x0c'),
b'n' => self.str_buf.push(b'\n'),
b'r' => self.str_buf.push(b'\r'),
b't' => self.str_buf.push(b'\t'),
b'u' => {
let c = match try!(self.decode_hex_escape()) {
0xDC00 ... 0xDFFF => {
return Err(self.error(ErrorCode::LoneLeadingSurrogateInHexEscape));
}
let n = (((n1 - 0xD800) as u32) << 10 |
(n2 - 0xDC00) as u32) + 0x1_0000;
// Non-BMP characters are encoded as a sequence of
// two hex escapes, representing UTF-16 surrogates.
n1 @ 0xD800 ... 0xDBFF => {
match (try!(self.next_char()), try!(self.next_char())) {
(Some(b'\\'), Some(b'u')) => (),
_ => {
return Err(self.error(ErrorCode::UnexpectedEndOfHexEscape));
}
}
match char::from_u32(n as u32) {
Some(c) => c,
None => {
return Err(self.error(ErrorCode::InvalidUnicodeCodePoint));
let n2 = try!(self.decode_hex_escape());
if n2 < 0xDC00 || n2 > 0xDFFF {
return Err(self.error(ErrorCode::LoneLeadingSurrogateInHexEscape));
}
let n = (((n1 - 0xD800) as u32) << 10 |
(n2 - 0xDC00) as u32) + 0x1_0000;
match char::from_u32(n as u32) {
Some(c) => c,
None => {
return Err(self.error(ErrorCode::InvalidUnicodeCodePoint));
}
}
}
}
n => {
match char::from_u32(n as u32) {
Some(c) => c,
None => {
return Err(self.error(ErrorCode::InvalidUnicodeCodePoint));
n => {
match char::from_u32(n as u32) {
Some(c) => c,
None => {
return Err(self.error(ErrorCode::InvalidUnicodeCodePoint));
}
}
}
}
};
};
// FIXME: this allocation is required in order to be compatible with stable
// rust, which doesn't support encoding a `char` into a stack buffer.
let buf = c.to_string();
self.str_buf.extend(buf.bytes());
}
_ => {
return Err(self.error(ErrorCode::InvalidEscape));
// FIXME: this allocation is required in order to be compatible with stable
// rust, which doesn't support encoding a `char` into a stack buffer.
let buf = c.to_string();
self.str_buf.extend(buf.bytes());
}
_ => {
return Err(self.error(ErrorCode::InvalidEscape));
}
}
}
escape = false;
} else {
match ch {
b'"' => {
try!(self.bump());
return Ok(());
}
b'\\' => {
escape = true;
}
ch => {
self.str_buf.push(ch);
}
ch => {
self.str_buf.push(ch);
}
}
}