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Diffstat (limited to '1.0.107/src/lit.rs')
-rw-r--r-- | 1.0.107/src/lit.rs | 1600 |
1 files changed, 0 insertions, 1600 deletions
diff --git a/1.0.107/src/lit.rs b/1.0.107/src/lit.rs deleted file mode 100644 index 130b40ed..00000000 --- a/1.0.107/src/lit.rs +++ /dev/null @@ -1,1600 +0,0 @@ -#[cfg(feature = "parsing")] -use crate::lookahead; -#[cfg(feature = "parsing")] -use crate::parse::{Parse, Parser}; -use crate::{Error, Result}; -use proc_macro2::{Ident, Literal, Span}; -#[cfg(feature = "parsing")] -use proc_macro2::{TokenStream, TokenTree}; -use std::fmt::{self, Display}; -#[cfg(feature = "extra-traits")] -use std::hash::{Hash, Hasher}; -use std::str::{self, FromStr}; - -ast_enum_of_structs! { - /// A Rust literal such as a string or integer or boolean. - /// - /// # Syntax tree enum - /// - /// This type is a [syntax tree enum]. - /// - /// [syntax tree enum]: crate::Expr#syntax-tree-enums - pub enum Lit { - /// A UTF-8 string literal: `"foo"`. - Str(LitStr), - - /// A byte string literal: `b"foo"`. - ByteStr(LitByteStr), - - /// A byte literal: `b'f'`. - Byte(LitByte), - - /// A character literal: `'a'`. - Char(LitChar), - - /// An integer literal: `1` or `1u16`. - Int(LitInt), - - /// A floating point literal: `1f64` or `1.0e10f64`. - /// - /// Must be finite. May not be infinite or NaN. - Float(LitFloat), - - /// A boolean literal: `true` or `false`. - Bool(LitBool), - - /// A raw token literal not interpreted by Syn. - Verbatim(Literal), - } -} - -ast_struct! { - /// A UTF-8 string literal: `"foo"`. - pub struct LitStr { - repr: Box<LitRepr>, - } -} - -ast_struct! { - /// A byte string literal: `b"foo"`. - pub struct LitByteStr { - repr: Box<LitRepr>, - } -} - -ast_struct! { - /// A byte literal: `b'f'`. - pub struct LitByte { - repr: Box<LitRepr>, - } -} - -ast_struct! { - /// A character literal: `'a'`. - pub struct LitChar { - repr: Box<LitRepr>, - } -} - -struct LitRepr { - token: Literal, - suffix: Box<str>, -} - -ast_struct! { - /// An integer literal: `1` or `1u16`. - pub struct LitInt { - repr: Box<LitIntRepr>, - } -} - -struct LitIntRepr { - token: Literal, - digits: Box<str>, - suffix: Box<str>, -} - -ast_struct! { - /// A floating point literal: `1f64` or `1.0e10f64`. - /// - /// Must be finite. May not be infinite or NaN. - pub struct LitFloat { - repr: Box<LitFloatRepr>, - } -} - -struct LitFloatRepr { - token: Literal, - digits: Box<str>, - suffix: Box<str>, -} - -ast_struct! { - /// A boolean literal: `true` or `false`. - pub struct LitBool { - pub value: bool, - pub span: Span, - } -} - -impl LitStr { - pub fn new(value: &str, span: Span) -> Self { - let mut token = Literal::string(value); - token.set_span(span); - LitStr { - repr: Box::new(LitRepr { - token, - suffix: Box::<str>::default(), - }), - } - } - - pub fn value(&self) -> String { - let repr = self.repr.token.to_string(); - let (value, _suffix) = value::parse_lit_str(&repr); - String::from(value) - } - - /// Parse a syntax tree node from the content of this string literal. - /// - /// All spans in the syntax tree will point to the span of this `LitStr`. - /// - /// # Example - /// - /// ``` - /// use proc_macro2::Span; - /// use syn::{Attribute, Error, Ident, Lit, Meta, MetaNameValue, Path, Result}; - /// - /// // Parses the path from an attribute that looks like: - /// // - /// // #[path = "a::b::c"] - /// // - /// // or returns `None` if the input is some other attribute. - /// fn get_path(attr: &Attribute) -> Result<Option<Path>> { - /// if !attr.path.is_ident("path") { - /// return Ok(None); - /// } - /// - /// match attr.parse_meta()? { - /// Meta::NameValue(MetaNameValue { lit: Lit::Str(lit_str), .. }) => { - /// lit_str.parse().map(Some) - /// } - /// _ => { - /// let message = "expected #[path = \"...\"]"; - /// Err(Error::new_spanned(attr, message)) - /// } - /// } - /// } - /// ``` - #[cfg(feature = "parsing")] - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - pub fn parse<T: Parse>(&self) -> Result<T> { - self.parse_with(T::parse) - } - - /// Invoke parser on the content of this string literal. - /// - /// All spans in the syntax tree will point to the span of this `LitStr`. - /// - /// # Example - /// - /// ``` - /// # use proc_macro2::Span; - /// # use syn::{LitStr, Result}; - /// # - /// # fn main() -> Result<()> { - /// # let lit_str = LitStr::new("a::b::c", Span::call_site()); - /// # - /// # const IGNORE: &str = stringify! { - /// let lit_str: LitStr = /* ... */; - /// # }; - /// - /// // Parse a string literal like "a::b::c" into a Path, not allowing - /// // generic arguments on any of the path segments. - /// let basic_path = lit_str.parse_with(syn::Path::parse_mod_style)?; - /// # - /// # Ok(()) - /// # } - /// ``` - #[cfg(feature = "parsing")] - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - pub fn parse_with<F: Parser>(&self, parser: F) -> Result<F::Output> { - use proc_macro2::Group; - - // Token stream with every span replaced by the given one. - fn respan_token_stream(stream: TokenStream, span: Span) -> TokenStream { - stream - .into_iter() - .map(|token| respan_token_tree(token, span)) - .collect() - } - - // Token tree with every span replaced by the given one. - fn respan_token_tree(mut token: TokenTree, span: Span) -> TokenTree { - match &mut token { - TokenTree::Group(g) => { - let stream = respan_token_stream(g.stream(), span); - *g = Group::new(g.delimiter(), stream); - g.set_span(span); - } - other => other.set_span(span), - } - token - } - - // Parse string literal into a token stream with every span equal to the - // original literal's span. - let mut tokens = TokenStream::from_str(&self.value())?; - tokens = respan_token_stream(tokens, self.span()); - - parser.parse2(tokens) - } - - pub fn span(&self) -> Span { - self.repr.token.span() - } - - pub fn set_span(&mut self, span: Span) { - self.repr.token.set_span(span); - } - - pub fn suffix(&self) -> &str { - &self.repr.suffix - } - - pub fn token(&self) -> Literal { - self.repr.token.clone() - } -} - -impl LitByteStr { - pub fn new(value: &[u8], span: Span) -> Self { - let mut token = Literal::byte_string(value); - token.set_span(span); - LitByteStr { - repr: Box::new(LitRepr { - token, - suffix: Box::<str>::default(), - }), - } - } - - pub fn value(&self) -> Vec<u8> { - let repr = self.repr.token.to_string(); - let (value, _suffix) = value::parse_lit_byte_str(&repr); - value - } - - pub fn span(&self) -> Span { - self.repr.token.span() - } - - pub fn set_span(&mut self, span: Span) { - self.repr.token.set_span(span); - } - - pub fn suffix(&self) -> &str { - &self.repr.suffix - } - - pub fn token(&self) -> Literal { - self.repr.token.clone() - } -} - -impl LitByte { - pub fn new(value: u8, span: Span) -> Self { - let mut token = Literal::u8_suffixed(value); - token.set_span(span); - LitByte { - repr: Box::new(LitRepr { - token, - suffix: Box::<str>::default(), - }), - } - } - - pub fn value(&self) -> u8 { - let repr = self.repr.token.to_string(); - let (value, _suffix) = value::parse_lit_byte(&repr); - value - } - - pub fn span(&self) -> Span { - self.repr.token.span() - } - - pub fn set_span(&mut self, span: Span) { - self.repr.token.set_span(span); - } - - pub fn suffix(&self) -> &str { - &self.repr.suffix - } - - pub fn token(&self) -> Literal { - self.repr.token.clone() - } -} - -impl LitChar { - pub fn new(value: char, span: Span) -> Self { - let mut token = Literal::character(value); - token.set_span(span); - LitChar { - repr: Box::new(LitRepr { - token, - suffix: Box::<str>::default(), - }), - } - } - - pub fn value(&self) -> char { - let repr = self.repr.token.to_string(); - let (value, _suffix) = value::parse_lit_char(&repr); - value - } - - pub fn span(&self) -> Span { - self.repr.token.span() - } - - pub fn set_span(&mut self, span: Span) { - self.repr.token.set_span(span); - } - - pub fn suffix(&self) -> &str { - &self.repr.suffix - } - - pub fn token(&self) -> Literal { - self.repr.token.clone() - } -} - -impl LitInt { - pub fn new(repr: &str, span: Span) -> Self { - let (digits, suffix) = match value::parse_lit_int(repr) { - Some(parse) => parse, - None => panic!("Not an integer literal: `{}`", repr), - }; - - let mut token = match value::to_literal(repr, &digits, &suffix) { - Some(token) => token, - None => panic!("Unsupported integer literal: `{}`", repr), - }; - - token.set_span(span); - LitInt { - repr: Box::new(LitIntRepr { - token, - digits, - suffix, - }), - } - } - - pub fn base10_digits(&self) -> &str { - &self.repr.digits - } - - /// Parses the literal into a selected number type. - /// - /// This is equivalent to `lit.base10_digits().parse()` except that the - /// resulting errors will be correctly spanned to point to the literal token - /// in the macro input. - /// - /// ``` - /// use syn::LitInt; - /// use syn::parse::{Parse, ParseStream, Result}; - /// - /// struct Port { - /// value: u16, - /// } - /// - /// impl Parse for Port { - /// fn parse(input: ParseStream) -> Result<Self> { - /// let lit: LitInt = input.parse()?; - /// let value = lit.base10_parse::<u16>()?; - /// Ok(Port { value }) - /// } - /// } - /// ``` - pub fn base10_parse<N>(&self) -> Result<N> - where - N: FromStr, - N::Err: Display, - { - self.base10_digits() - .parse() - .map_err(|err| Error::new(self.span(), err)) - } - - pub fn suffix(&self) -> &str { - &self.repr.suffix - } - - pub fn span(&self) -> Span { - self.repr.token.span() - } - - pub fn set_span(&mut self, span: Span) { - self.repr.token.set_span(span); - } - - pub fn token(&self) -> Literal { - self.repr.token.clone() - } -} - -impl From<Literal> for LitInt { - fn from(token: Literal) -> Self { - let repr = token.to_string(); - if let Some((digits, suffix)) = value::parse_lit_int(&repr) { - LitInt { - repr: Box::new(LitIntRepr { - token, - digits, - suffix, - }), - } - } else { - panic!("Not an integer literal: `{}`", repr); - } - } -} - -impl Display for LitInt { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - self.repr.token.fmt(formatter) - } -} - -impl LitFloat { - pub fn new(repr: &str, span: Span) -> Self { - let (digits, suffix) = match value::parse_lit_float(repr) { - Some(parse) => parse, - None => panic!("Not a float literal: `{}`", repr), - }; - - let mut token = match value::to_literal(repr, &digits, &suffix) { - Some(token) => token, - None => panic!("Unsupported float literal: `{}`", repr), - }; - - token.set_span(span); - LitFloat { - repr: Box::new(LitFloatRepr { - token, - digits, - suffix, - }), - } - } - - pub fn base10_digits(&self) -> &str { - &self.repr.digits - } - - pub fn base10_parse<N>(&self) -> Result<N> - where - N: FromStr, - N::Err: Display, - { - self.base10_digits() - .parse() - .map_err(|err| Error::new(self.span(), err)) - } - - pub fn suffix(&self) -> &str { - &self.repr.suffix - } - - pub fn span(&self) -> Span { - self.repr.token.span() - } - - pub fn set_span(&mut self, span: Span) { - self.repr.token.set_span(span); - } - - pub fn token(&self) -> Literal { - self.repr.token.clone() - } -} - -impl From<Literal> for LitFloat { - fn from(token: Literal) -> Self { - let repr = token.to_string(); - if let Some((digits, suffix)) = value::parse_lit_float(&repr) { - LitFloat { - repr: Box::new(LitFloatRepr { - token, - digits, - suffix, - }), - } - } else { - panic!("Not a float literal: `{}`", repr); - } - } -} - -impl Display for LitFloat { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - self.repr.token.fmt(formatter) - } -} - -impl LitBool { - pub fn new(value: bool, span: Span) -> Self { - LitBool { value, span } - } - - pub fn value(&self) -> bool { - self.value - } - - pub fn span(&self) -> Span { - self.span - } - - pub fn set_span(&mut self, span: Span) { - self.span = span; - } - - pub fn token(&self) -> Ident { - let s = if self.value { "true" } else { "false" }; - Ident::new(s, self.span) - } -} - -#[cfg(feature = "extra-traits")] -mod debug_impls { - use super::*; - use std::fmt::{self, Debug}; - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitStr { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitStr") - .field("token", &format_args!("{}", self.repr.token)) - .finish() - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitByteStr { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitByteStr") - .field("token", &format_args!("{}", self.repr.token)) - .finish() - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitByte { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitByte") - .field("token", &format_args!("{}", self.repr.token)) - .finish() - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitChar { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitChar") - .field("token", &format_args!("{}", self.repr.token)) - .finish() - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitInt { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitInt") - .field("token", &format_args!("{}", self.repr.token)) - .finish() - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitFloat { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitFloat") - .field("token", &format_args!("{}", self.repr.token)) - .finish() - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Debug for LitBool { - fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { - formatter - .debug_struct("LitBool") - .field("value", &self.value) - .finish() - } - } -} - -#[cfg(feature = "clone-impls")] -#[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))] -impl Clone for LitRepr { - fn clone(&self) -> Self { - LitRepr { - token: self.token.clone(), - suffix: self.suffix.clone(), - } - } -} - -#[cfg(feature = "clone-impls")] -#[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))] -impl Clone for LitIntRepr { - fn clone(&self) -> Self { - LitIntRepr { - token: self.token.clone(), - digits: self.digits.clone(), - suffix: self.suffix.clone(), - } - } -} - -#[cfg(feature = "clone-impls")] -#[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))] -impl Clone for LitFloatRepr { - fn clone(&self) -> Self { - LitFloatRepr { - token: self.token.clone(), - digits: self.digits.clone(), - suffix: self.suffix.clone(), - } - } -} - -macro_rules! lit_extra_traits { - ($ty:ident) => { - #[cfg(feature = "clone-impls")] - #[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))] - impl Clone for $ty { - fn clone(&self) -> Self { - $ty { - repr: self.repr.clone(), - } - } - } - - #[cfg(feature = "extra-traits")] - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl PartialEq for $ty { - fn eq(&self, other: &Self) -> bool { - self.repr.token.to_string() == other.repr.token.to_string() - } - } - - #[cfg(feature = "extra-traits")] - #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))] - impl Hash for $ty { - fn hash<H>(&self, state: &mut H) - where - H: Hasher, - { - self.repr.token.to_string().hash(state); - } - } - - #[cfg(feature = "parsing")] - #[doc(hidden)] - #[allow(non_snake_case)] - pub fn $ty(marker: lookahead::TokenMarker) -> $ty { - match marker {} - } - }; -} - -lit_extra_traits!(LitStr); -lit_extra_traits!(LitByteStr); -lit_extra_traits!(LitByte); -lit_extra_traits!(LitChar); -lit_extra_traits!(LitInt); -lit_extra_traits!(LitFloat); - -#[cfg(feature = "parsing")] -#[doc(hidden)] -#[allow(non_snake_case)] -pub fn LitBool(marker: lookahead::TokenMarker) -> LitBool { - match marker {} -} - -ast_enum! { - /// The style of a string literal, either plain quoted or a raw string like - /// `r##"data"##`. - pub enum StrStyle #no_visit { - /// An ordinary string like `"data"`. - Cooked, - /// A raw string like `r##"data"##`. - /// - /// The unsigned integer is the number of `#` symbols used. - Raw(usize), - } -} - -#[cfg(feature = "parsing")] -#[doc(hidden)] -#[allow(non_snake_case)] -pub fn Lit(marker: lookahead::TokenMarker) -> Lit { - match marker {} -} - -#[cfg(feature = "parsing")] -pub mod parsing { - use super::*; - use crate::buffer::Cursor; - use crate::parse::{Parse, ParseStream, Result}; - use proc_macro2::Punct; - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for Lit { - fn parse(input: ParseStream) -> Result<Self> { - input.step(|cursor| { - if let Some((lit, rest)) = cursor.literal() { - return Ok((Lit::new(lit), rest)); - } - - if let Some((ident, rest)) = cursor.ident() { - let value = ident == "true"; - if value || ident == "false" { - let lit_bool = LitBool { - value, - span: ident.span(), - }; - return Ok((Lit::Bool(lit_bool), rest)); - } - } - - if let Some((punct, rest)) = cursor.punct() { - if punct.as_char() == '-' { - if let Some((lit, rest)) = parse_negative_lit(punct, rest) { - return Ok((lit, rest)); - } - } - } - - Err(cursor.error("expected literal")) - }) - } - } - - fn parse_negative_lit(neg: Punct, cursor: Cursor) -> Option<(Lit, Cursor)> { - let (lit, rest) = cursor.literal()?; - - let mut span = neg.span(); - span = span.join(lit.span()).unwrap_or(span); - - let mut repr = lit.to_string(); - repr.insert(0, '-'); - - if let Some((digits, suffix)) = value::parse_lit_int(&repr) { - if let Some(mut token) = value::to_literal(&repr, &digits, &suffix) { - token.set_span(span); - return Some(( - Lit::Int(LitInt { - repr: Box::new(LitIntRepr { - token, - digits, - suffix, - }), - }), - rest, - )); - } - } - - let (digits, suffix) = value::parse_lit_float(&repr)?; - let mut token = value::to_literal(&repr, &digits, &suffix)?; - token.set_span(span); - Some(( - Lit::Float(LitFloat { - repr: Box::new(LitFloatRepr { - token, - digits, - suffix, - }), - }), - rest, - )) - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitStr { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::Str(lit)) => Ok(lit), - _ => Err(head.error("expected string literal")), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitByteStr { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::ByteStr(lit)) => Ok(lit), - _ => Err(head.error("expected byte string literal")), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitByte { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::Byte(lit)) => Ok(lit), - _ => Err(head.error("expected byte literal")), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitChar { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::Char(lit)) => Ok(lit), - _ => Err(head.error("expected character literal")), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitInt { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::Int(lit)) => Ok(lit), - _ => Err(head.error("expected integer literal")), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitFloat { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::Float(lit)) => Ok(lit), - _ => Err(head.error("expected floating point literal")), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for LitBool { - fn parse(input: ParseStream) -> Result<Self> { - let head = input.fork(); - match input.parse() { - Ok(Lit::Bool(lit)) => Ok(lit), - _ => Err(head.error("expected boolean literal")), - } - } - } -} - -#[cfg(feature = "printing")] -mod printing { - use super::*; - use proc_macro2::TokenStream; - use quote::{ToTokens, TokenStreamExt}; - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitStr { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.repr.token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitByteStr { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.repr.token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitByte { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.repr.token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitChar { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.repr.token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitInt { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.repr.token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitFloat { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.repr.token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for LitBool { - fn to_tokens(&self, tokens: &mut TokenStream) { - tokens.append(self.token()); - } - } -} - -mod value { - use super::*; - use crate::bigint::BigInt; - use std::char; - use std::ops::{Index, RangeFrom}; - - impl Lit { - /// Interpret a Syn literal from a proc-macro2 literal. - pub fn new(token: Literal) -> Self { - let repr = token.to_string(); - - match byte(&repr, 0) { - b'"' | b'r' => { - let (_, suffix) = parse_lit_str(&repr); - return Lit::Str(LitStr { - repr: Box::new(LitRepr { token, suffix }), - }); - } - b'b' => match byte(&repr, 1) { - b'"' | b'r' => { - let (_, suffix) = parse_lit_byte_str(&repr); - return Lit::ByteStr(LitByteStr { - repr: Box::new(LitRepr { token, suffix }), - }); - } - b'\'' => { - let (_, suffix) = parse_lit_byte(&repr); - return Lit::Byte(LitByte { - repr: Box::new(LitRepr { token, suffix }), - }); - } - _ => {} - }, - b'\'' => { - let (_, suffix) = parse_lit_char(&repr); - return Lit::Char(LitChar { - repr: Box::new(LitRepr { token, suffix }), - }); - } - b'0'..=b'9' | b'-' => { - if let Some((digits, suffix)) = parse_lit_int(&repr) { - return Lit::Int(LitInt { - repr: Box::new(LitIntRepr { - token, - digits, - suffix, - }), - }); - } - if let Some((digits, suffix)) = parse_lit_float(&repr) { - return Lit::Float(LitFloat { - repr: Box::new(LitFloatRepr { - token, - digits, - suffix, - }), - }); - } - } - b't' | b'f' => { - if repr == "true" || repr == "false" { - return Lit::Bool(LitBool { - value: repr == "true", - span: token.span(), - }); - } - } - _ => {} - } - - panic!("Unrecognized literal: `{}`", repr); - } - - pub fn suffix(&self) -> &str { - match self { - Lit::Str(lit) => lit.suffix(), - Lit::ByteStr(lit) => lit.suffix(), - Lit::Byte(lit) => lit.suffix(), - Lit::Char(lit) => lit.suffix(), - Lit::Int(lit) => lit.suffix(), - Lit::Float(lit) => lit.suffix(), - Lit::Bool(_) | Lit::Verbatim(_) => "", - } - } - - pub fn span(&self) -> Span { - match self { - Lit::Str(lit) => lit.span(), - Lit::ByteStr(lit) => lit.span(), - Lit::Byte(lit) => lit.span(), - Lit::Char(lit) => lit.span(), - Lit::Int(lit) => lit.span(), - Lit::Float(lit) => lit.span(), - Lit::Bool(lit) => lit.span, - Lit::Verbatim(lit) => lit.span(), - } - } - - pub fn set_span(&mut self, span: Span) { - match self { - Lit::Str(lit) => lit.set_span(span), - Lit::ByteStr(lit) => lit.set_span(span), - Lit::Byte(lit) => lit.set_span(span), - Lit::Char(lit) => lit.set_span(span), - Lit::Int(lit) => lit.set_span(span), - Lit::Float(lit) => lit.set_span(span), - Lit::Bool(lit) => lit.span = span, - Lit::Verbatim(lit) => lit.set_span(span), - } - } - } - - /// Get the byte at offset idx, or a default of `b'\0'` if we're looking - /// past the end of the input buffer. - pub fn byte<S: AsRef<[u8]> + ?Sized>(s: &S, idx: usize) -> u8 { - let s = s.as_ref(); - if idx < s.len() { - s[idx] - } else { - 0 - } - } - - fn next_chr(s: &str) -> char { - s.chars().next().unwrap_or('\0') - } - - // Returns (content, suffix). - pub fn parse_lit_str(s: &str) -> (Box<str>, Box<str>) { - match byte(s, 0) { - b'"' => parse_lit_str_cooked(s), - b'r' => parse_lit_str_raw(s), - _ => unreachable!(), - } - } - - // Clippy false positive - // https://github.com/rust-lang-nursery/rust-clippy/issues/2329 - #[allow(clippy::needless_continue)] - fn parse_lit_str_cooked(mut s: &str) -> (Box<str>, Box<str>) { - assert_eq!(byte(s, 0), b'"'); - s = &s[1..]; - - let mut content = String::new(); - 'outer: loop { - let ch = match byte(s, 0) { - b'"' => break, - b'\\' => { - let b = byte(s, 1); - s = &s[2..]; - match b { - b'x' => { - let (byte, rest) = backslash_x(s); - s = rest; - assert!(byte <= 0x80, "Invalid \\x byte in string literal"); - char::from_u32(u32::from(byte)).unwrap() - } - b'u' => { - let (chr, rest) = backslash_u(s); - s = rest; - chr - } - b'n' => '\n', - b'r' => '\r', - b't' => '\t', - b'\\' => '\\', - b'0' => '\0', - b'\'' => '\'', - b'"' => '"', - b'\r' | b'\n' => loop { - let ch = next_chr(s); - if ch.is_whitespace() { - s = &s[ch.len_utf8()..]; - } else { - continue 'outer; - } - }, - b => panic!("unexpected byte {:?} after \\ character in byte literal", b), - } - } - b'\r' => { - assert_eq!(byte(s, 1), b'\n', "Bare CR not allowed in string"); - s = &s[2..]; - '\n' - } - _ => { - let ch = next_chr(s); - s = &s[ch.len_utf8()..]; - ch - } - }; - content.push(ch); - } - - assert!(s.starts_with('"')); - let content = content.into_boxed_str(); - let suffix = s[1..].to_owned().into_boxed_str(); - (content, suffix) - } - - fn parse_lit_str_raw(mut s: &str) -> (Box<str>, Box<str>) { - assert_eq!(byte(s, 0), b'r'); - s = &s[1..]; - - let mut pounds = 0; - while byte(s, pounds) == b'#' { - pounds += 1; - } - assert_eq!(byte(s, pounds), b'"'); - let close = s.rfind('"').unwrap(); - for end in s[close + 1..close + 1 + pounds].bytes() { - assert_eq!(end, b'#'); - } - - let content = s[pounds + 1..close].to_owned().into_boxed_str(); - let suffix = s[close + 1 + pounds..].to_owned().into_boxed_str(); - (content, suffix) - } - - // Returns (content, suffix). - pub fn parse_lit_byte_str(s: &str) -> (Vec<u8>, Box<str>) { - assert_eq!(byte(s, 0), b'b'); - match byte(s, 1) { - b'"' => parse_lit_byte_str_cooked(s), - b'r' => parse_lit_byte_str_raw(s), - _ => unreachable!(), - } - } - - // Clippy false positive - // https://github.com/rust-lang-nursery/rust-clippy/issues/2329 - #[allow(clippy::needless_continue)] - fn parse_lit_byte_str_cooked(mut s: &str) -> (Vec<u8>, Box<str>) { - assert_eq!(byte(s, 0), b'b'); - assert_eq!(byte(s, 1), b'"'); - s = &s[2..]; - - // We're going to want to have slices which don't respect codepoint boundaries. - let mut v = s.as_bytes(); - - let mut out = Vec::new(); - 'outer: loop { - let byte = match byte(v, 0) { - b'"' => break, - b'\\' => { - let b = byte(v, 1); - v = &v[2..]; - match b { - b'x' => { - let (b, rest) = backslash_x(v); - v = rest; - b - } - b'n' => b'\n', - b'r' => b'\r', - b't' => b'\t', - b'\\' => b'\\', - b'0' => b'\0', - b'\'' => b'\'', - b'"' => b'"', - b'\r' | b'\n' => loop { - let byte = byte(v, 0); - let ch = char::from_u32(u32::from(byte)).unwrap(); - if ch.is_whitespace() { - v = &v[1..]; - } else { - continue 'outer; - } - }, - b => panic!("unexpected byte {:?} after \\ character in byte literal", b), - } - } - b'\r' => { - assert_eq!(byte(v, 1), b'\n', "Bare CR not allowed in string"); - v = &v[2..]; - b'\n' - } - b => { - v = &v[1..]; - b - } - }; - out.push(byte); - } - - assert_eq!(byte(v, 0), b'"'); - let suffix = s[s.len() - v.len() + 1..].to_owned().into_boxed_str(); - (out, suffix) - } - - fn parse_lit_byte_str_raw(s: &str) -> (Vec<u8>, Box<str>) { - assert_eq!(byte(s, 0), b'b'); - let (value, suffix) = parse_lit_str_raw(&s[1..]); - (String::from(value).into_bytes(), suffix) - } - - // Returns (value, suffix). - pub fn parse_lit_byte(s: &str) -> (u8, Box<str>) { - assert_eq!(byte(s, 0), b'b'); - assert_eq!(byte(s, 1), b'\''); - - // We're going to want to have slices which don't respect codepoint boundaries. - let mut v = s[2..].as_bytes(); - - let b = match byte(v, 0) { - b'\\' => { - let b = byte(v, 1); - v = &v[2..]; - match b { - b'x' => { - let (b, rest) = backslash_x(v); - v = rest; - b - } - b'n' => b'\n', - b'r' => b'\r', - b't' => b'\t', - b'\\' => b'\\', - b'0' => b'\0', - b'\'' => b'\'', - b'"' => b'"', - b => panic!("unexpected byte {:?} after \\ character in byte literal", b), - } - } - b => { - v = &v[1..]; - b - } - }; - - assert_eq!(byte(v, 0), b'\''); - let suffix = s[s.len() - v.len() + 1..].to_owned().into_boxed_str(); - (b, suffix) - } - - // Returns (value, suffix). - pub fn parse_lit_char(mut s: &str) -> (char, Box<str>) { - assert_eq!(byte(s, 0), b'\''); - s = &s[1..]; - - let ch = match byte(s, 0) { - b'\\' => { - let b = byte(s, 1); - s = &s[2..]; - match b { - b'x' => { - let (byte, rest) = backslash_x(s); - s = rest; - assert!(byte <= 0x80, "Invalid \\x byte in string literal"); - char::from_u32(u32::from(byte)).unwrap() - } - b'u' => { - let (chr, rest) = backslash_u(s); - s = rest; - chr - } - b'n' => '\n', - b'r' => '\r', - b't' => '\t', - b'\\' => '\\', - b'0' => '\0', - b'\'' => '\'', - b'"' => '"', - b => panic!("unexpected byte {:?} after \\ character in byte literal", b), - } - } - _ => { - let ch = next_chr(s); - s = &s[ch.len_utf8()..]; - ch - } - }; - assert_eq!(byte(s, 0), b'\''); - let suffix = s[1..].to_owned().into_boxed_str(); - (ch, suffix) - } - - fn backslash_x<S>(s: &S) -> (u8, &S) - where - S: Index<RangeFrom<usize>, Output = S> + AsRef<[u8]> + ?Sized, - { - let mut ch = 0; - let b0 = byte(s, 0); - let b1 = byte(s, 1); - ch += 0x10 - * match b0 { - b'0'..=b'9' => b0 - b'0', - b'a'..=b'f' => 10 + (b0 - b'a'), - b'A'..=b'F' => 10 + (b0 - b'A'), - _ => panic!("unexpected non-hex character after \\x"), - }; - ch += match b1 { - b'0'..=b'9' => b1 - b'0', - b'a'..=b'f' => 10 + (b1 - b'a'), - b'A'..=b'F' => 10 + (b1 - b'A'), - _ => panic!("unexpected non-hex character after \\x"), - }; - (ch, &s[2..]) - } - - fn backslash_u(mut s: &str) -> (char, &str) { - if byte(s, 0) != b'{' { - panic!("{}", "expected { after \\u"); - } - s = &s[1..]; - - let mut ch = 0; - let mut digits = 0; - loop { - let b = byte(s, 0); - let digit = match b { - b'0'..=b'9' => b - b'0', - b'a'..=b'f' => 10 + b - b'a', - b'A'..=b'F' => 10 + b - b'A', - b'_' if digits > 0 => { - s = &s[1..]; - continue; - } - b'}' if digits == 0 => panic!("invalid empty unicode escape"), - b'}' => break, - _ => panic!("unexpected non-hex character after \\u"), - }; - if digits == 6 { - panic!("overlong unicode escape (must have at most 6 hex digits)"); - } - ch *= 0x10; - ch += u32::from(digit); - digits += 1; - s = &s[1..]; - } - assert!(byte(s, 0) == b'}'); - s = &s[1..]; - - if let Some(ch) = char::from_u32(ch) { - (ch, s) - } else { - panic!("character code {:x} is not a valid unicode character", ch); - } - } - - // Returns base 10 digits and suffix. - pub fn parse_lit_int(mut s: &str) -> Option<(Box<str>, Box<str>)> { - let negative = byte(s, 0) == b'-'; - if negative { - s = &s[1..]; - } - - let base = match (byte(s, 0), byte(s, 1)) { - (b'0', b'x') => { - s = &s[2..]; - 16 - } - (b'0', b'o') => { - s = &s[2..]; - 8 - } - (b'0', b'b') => { - s = &s[2..]; - 2 - } - (b'0'..=b'9', _) => 10, - _ => return None, - }; - - let mut value = BigInt::new(); - 'outer: loop { - let b = byte(s, 0); - let digit = match b { - b'0'..=b'9' => b - b'0', - b'a'..=b'f' if base > 10 => b - b'a' + 10, - b'A'..=b'F' if base > 10 => b - b'A' + 10, - b'_' => { - s = &s[1..]; - continue; - } - // If looking at a floating point literal, we don't want to - // consider it an integer. - b'.' if base == 10 => return None, - b'e' | b'E' if base == 10 => { - let mut has_exp = false; - for (i, b) in s[1..].bytes().enumerate() { - match b { - b'_' => {} - b'-' | b'+' => return None, - b'0'..=b'9' => has_exp = true, - _ => { - let suffix = &s[1 + i..]; - if has_exp && crate::ident::xid_ok(suffix) { - return None; - } else { - break 'outer; - } - } - } - } - if has_exp { - return None; - } else { - break; - } - } - _ => break, - }; - - if digit >= base { - return None; - } - - value *= base; - value += digit; - s = &s[1..]; - } - - let suffix = s; - if suffix.is_empty() || crate::ident::xid_ok(suffix) { - let mut repr = value.to_string(); - if negative { - repr.insert(0, '-'); - } - Some((repr.into_boxed_str(), suffix.to_owned().into_boxed_str())) - } else { - None - } - } - - // Returns base 10 digits and suffix. - pub fn parse_lit_float(input: &str) -> Option<(Box<str>, Box<str>)> { - // Rust's floating point literals are very similar to the ones parsed by - // the standard library, except that rust's literals can contain - // ignorable underscores. Let's remove those underscores. - - let mut bytes = input.to_owned().into_bytes(); - - let start = (*bytes.first()? == b'-') as usize; - match bytes.get(start)? { - b'0'..=b'9' => {} - _ => return None, - } - - let mut read = start; - let mut write = start; - let mut has_dot = false; - let mut has_e = false; - let mut has_sign = false; - let mut has_exponent = false; - while read < bytes.len() { - match bytes[read] { - b'_' => { - // Don't increase write - read += 1; - continue; - } - b'0'..=b'9' => { - if has_e { - has_exponent = true; - } - bytes[write] = bytes[read]; - } - b'.' => { - if has_e || has_dot { - return None; - } - has_dot = true; - bytes[write] = b'.'; - } - b'e' | b'E' => { - match bytes[read + 1..] - .iter() - .find(|b| **b != b'_') - .unwrap_or(&b'\0') - { - b'-' | b'+' | b'0'..=b'9' => {} - _ => break, - } - if has_e { - if has_exponent { - break; - } else { - return None; - } - } - has_e = true; - bytes[write] = b'e'; - } - b'-' | b'+' => { - if has_sign || has_exponent || !has_e { - return None; - } - has_sign = true; - if bytes[read] == b'-' { - bytes[write] = bytes[read]; - } else { - // Omit '+' - read += 1; - continue; - } - } - _ => break, - } - read += 1; - write += 1; - } - - if has_e && !has_exponent { - return None; - } - - let mut digits = String::from_utf8(bytes).unwrap(); - let suffix = digits.split_off(read); - digits.truncate(write); - if suffix.is_empty() || crate::ident::xid_ok(&suffix) { - Some((digits.into_boxed_str(), suffix.into_boxed_str())) - } else { - None - } - } - - #[allow(clippy::unnecessary_wraps)] - pub fn to_literal(repr: &str, digits: &str, suffix: &str) -> Option<Literal> { - #[cfg(syn_no_negative_literal_parse)] - { - // Rustc older than https://github.com/rust-lang/rust/pull/87262. - if repr.starts_with('-') { - let f64_parse_finite = || digits.parse().ok().filter(|x: &f64| x.is_finite()); - let f32_parse_finite = || digits.parse().ok().filter(|x: &f32| x.is_finite()); - return if suffix == "f64" { - f64_parse_finite().map(Literal::f64_suffixed) - } else if suffix == "f32" { - f32_parse_finite().map(Literal::f32_suffixed) - } else if suffix == "i64" { - digits.parse().ok().map(Literal::i64_suffixed) - } else if suffix == "i32" { - digits.parse().ok().map(Literal::i32_suffixed) - } else if suffix == "i16" { - digits.parse().ok().map(Literal::i16_suffixed) - } else if suffix == "i8" { - digits.parse().ok().map(Literal::i8_suffixed) - } else if !suffix.is_empty() { - None - } else if digits.contains('.') { - f64_parse_finite().map(Literal::f64_unsuffixed) - } else { - digits.parse().ok().map(Literal::i64_unsuffixed) - }; - } - } - let _ = digits; - let _ = suffix; - Some(repr.parse::<Literal>().unwrap()) - } -} |