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#![deny(missing_debug_implementations)]
extern crate proc_macro;
#[cfg(test)]
#[macro_use]
mod test_util;
#[cfg(test)]
mod tests;
mod bool;
mod byte;
mod bytestr;
mod char;
mod escape;
mod float;
mod integer;
mod parse;
mod string;
use std::{borrow::{Borrow, Cow}, fmt, ops::{Deref, Range}};
pub use self::{
bool::BoolLit,
byte::ByteLit,
bytestr::ByteStringLit,
char::CharLit,
float::{FloatLit, FloatType},
integer::{FromIntegerLiteral, IntegerLit, IntegerBase, IntegerType},
string::StringLit,
};
pub type OwnedLiteral = Literal<String>;
pub type SharedLiteral<'a> = Literal<&'a str>;
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Literal<B: Buffer> {
Bool(BoolLit),
Integer(IntegerLit<B>),
Float(FloatLit<B>),
Char(CharLit<B>),
String(StringLit<B>),
Byte(ByteLit<B>),
ByteString(ByteStringLit<B>),
}
impl Literal<&str> {
pub fn into_owned(self) -> OwnedLiteral {
match self {
Literal::Bool(l) => Literal::Bool(l.to_owned()),
Literal::Integer(l) => Literal::Integer(l.to_owned()),
Literal::Float(l) => Literal::Float(l.to_owned()),
Literal::Char(l) => Literal::Char(l.to_owned()),
Literal::String(l) => Literal::String(l.into_owned()),
Literal::Byte(l) => Literal::Byte(l.to_owned()),
Literal::ByteString(l) => Literal::ByteString(l.into_owned()),
}
}
}
impl<B: Buffer> fmt::Display for Literal<B> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Literal::Bool(l) => l.fmt(f),
Literal::Integer(l) => l.fmt(f),
Literal::Float(l) => l.fmt(f),
Literal::Char(l) => l.fmt(f),
Literal::String(l) => l.fmt(f),
Literal::Byte(l) => l.fmt(f),
Literal::ByteString(l) => l.fmt(f),
}
}
}
#[cfg(feature = "proc-macro")]
impl From<proc_macro::Literal> for Literal<String> {
fn from(src: proc_macro::Literal) -> Self {
Self::parse(src.to_string())
.expect("bug: failed to parse output of `Literal::to_string`")
}
}
#[cfg(feature = "proc-macro2")]
impl From<proc_macro2::Literal> for Literal<String> {
fn from(src: proc_macro2::Literal) -> Self {
Self::parse(src.to_string())
.expect("bug: failed to parse output of `Literal::to_string`")
}
}
#[derive(Debug, Clone)]
pub struct Error {
span: Option<Range<usize>>,
kind: ErrorKind,
}
impl Error {
pub fn span(&self) -> Option<Range<usize>> {
self.span.clone()
}
fn new(span: Range<usize>, kind: ErrorKind) -> Self {
Self {
span: Some(span),
kind,
}
}
fn single(at: usize, kind: ErrorKind) -> Self {
Self {
span: Some(at..at + 1),
kind,
}
}
fn spanless(kind: ErrorKind) -> Self {
Self {
span: None,
kind,
}
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[non_exhaustive]
enum ErrorKind {
Empty,
UnexpectedChar,
InvalidLiteral,
DoesNotStartWithDigit,
InvalidDigit,
NoDigits,
InvalidIntegerTypeSuffix,
InvalidFloatTypeSuffix,
NoExponentDigits,
UnknownEscape,
UnterminatedEscape,
InvalidXEscape,
NonAsciiXEscape,
UnicodeEscapeInByteLiteral,
InvalidStartOfUnicodeEscape,
UnicodeEscapeWithoutBrace,
NonHexDigitInUnicodeEscape,
TooManyDigitInUnicodeEscape,
InvalidUnicodeEscapeChar,
UnterminatedUnicodeEscape,
UnterminatedCharLiteral,
OverlongCharLiteral,
EmptyCharLiteral,
UnterminatedByteLiteral,
OverlongByteLiteral,
EmptyByteLiteral,
NonAsciiInByteLiteral,
UnescapedSingleQuote,
UnescapedSpecialWhitespace,
DoesNotStartWithQuote,
UnterminatedRawString,
UnterminatedString,
InvalidStringLiteralStart,
InvalidByteLiteralStart,
InvalidByteStringLiteralStart,
IsolatedCr,
}
impl std::error::Error for Error {}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use ErrorKind::*;
let description = match self.kind {
Empty => "input is empty",
UnexpectedChar => "unexpected character",
InvalidLiteral => "invalid literal",
DoesNotStartWithDigit => "number literal does not start with decimal digit",
InvalidDigit => "integer literal contains a digit invalid for its base",
NoDigits => "integer literal does not contain any digits",
InvalidIntegerTypeSuffix => "invalid integer type suffix",
InvalidFloatTypeSuffix => "invalid floating point type suffix",
NoExponentDigits => "exponent of floating point literal does not contain any digits",
UnknownEscape => "unknown escape",
UnterminatedEscape => "unterminated escape: input ended too soon",
InvalidXEscape => r"invalid `\x` escape: not followed by two hex digits",
NonAsciiXEscape => r"`\x` escape in char/string literal exceed ASCII range",
UnicodeEscapeInByteLiteral => r"`\u{...}` escape in byte (string) literal not allowed",
InvalidStartOfUnicodeEscape => r"invalid start of `\u{...}` escape",
UnicodeEscapeWithoutBrace => r"`Unicode \u{...}` escape without opening brace",
NonHexDigitInUnicodeEscape => r"non-hex digit found in `\u{...}` escape",
TooManyDigitInUnicodeEscape => r"more than six digits in `\u{...}` escape",
InvalidUnicodeEscapeChar => r"value specified in `\u{...}` escape is not a valid char",
UnterminatedUnicodeEscape => r"unterminated `\u{...}` escape",
UnterminatedCharLiteral => "character literal is not terminated",
OverlongCharLiteral => "character literal contains more than one character",
EmptyCharLiteral => "empty character literal",
UnterminatedByteLiteral => "byte literal is not terminated",
OverlongByteLiteral => "byte literal contains more than one byte",
EmptyByteLiteral => "empty byte literal",
NonAsciiInByteLiteral => "non ASCII character in byte (string) literal",
UnescapedSingleQuote => "character literal contains unescaped ' character",
UnescapedSpecialWhitespace => r"unescaped newline (\n), tab (\t) or cr (\r) character",
DoesNotStartWithQuote => "invalid start for char/byte/string literal",
UnterminatedRawString => "unterminated raw (byte) string literal",
UnterminatedString => "unterminated (byte) string literal",
InvalidStringLiteralStart => "invalid start for string literal",
InvalidByteLiteralStart => "invalid start for byte literal",
InvalidByteStringLiteralStart => "invalid start for byte string literal",
IsolatedCr => r"`\r` not immediately followed by `\n` in string",
};
description.fmt(f)?;
if let Some(span) = &self.span {
write!(f, " (at {}..{})", span.start, span.end)?;
}
Ok(())
}
}
pub trait Buffer: sealed::Sealed + Deref<Target = str> {
type Cow: From<String> + AsRef<str> + Borrow<str> + Deref<Target = str>;
#[doc(hidden)]
fn into_cow(self) -> Self::Cow;
type ByteCow: From<Vec<u8>> + AsRef<[u8]> + Borrow<[u8]> + Deref<Target = [u8]>;
#[doc(hidden)]
fn into_byte_cow(self) -> Self::ByteCow;
#[doc(hidden)]
fn cut(self, range: Range<usize>) -> Self;
}
mod sealed {
pub trait Sealed {}
}
impl<'a> sealed::Sealed for &'a str {}
impl<'a> Buffer for &'a str {
#[doc(hidden)]
fn cut(self, range: Range<usize>) -> Self {
&self[range]
}
type Cow = Cow<'a, str>;
#[doc(hidden)]
fn into_cow(self) -> Self::Cow {
self.into()
}
type ByteCow = Cow<'a, [u8]>;
#[doc(hidden)]
fn into_byte_cow(self) -> Self::ByteCow {
self.as_bytes().into()
}
}
impl sealed::Sealed for String {}
impl Buffer for String {
#[doc(hidden)]
fn cut(mut self, range: Range<usize>) -> Self {
self.truncate(range.end);
self.drain(..range.start);
self
}
type Cow = Cow<'static, str>;
#[doc(hidden)]
fn into_cow(self) -> Self::Cow {
self.into()
}
type ByteCow = Cow<'static, [u8]>;
#[doc(hidden)]
fn into_byte_cow(self) -> Self::ByteCow {
self.into_bytes().into()
}
}