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Diffstat (limited to '1.0.107/src/path.rs')
| -rw-r--r-- | 1.0.107/src/path.rs | 854 |
1 files changed, 0 insertions, 854 deletions
diff --git a/1.0.107/src/path.rs b/1.0.107/src/path.rs deleted file mode 100644 index 6cdb43ac..00000000 --- a/1.0.107/src/path.rs +++ /dev/null @@ -1,854 +0,0 @@ -use super::*; -use crate::punctuated::Punctuated; - -ast_struct! { - /// A path at which a named item is exported (e.g. `std::collections::HashMap`). - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct Path { - pub leading_colon: Option<Token![::]>, - pub segments: Punctuated<PathSegment, Token![::]>, - } -} - -impl<T> From<T> for Path -where - T: Into<PathSegment>, -{ - fn from(segment: T) -> Self { - let mut path = Path { - leading_colon: None, - segments: Punctuated::new(), - }; - path.segments.push_value(segment.into()); - path - } -} - -ast_struct! { - /// A segment of a path together with any path arguments on that segment. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct PathSegment { - pub ident: Ident, - pub arguments: PathArguments, - } -} - -impl<T> From<T> for PathSegment -where - T: Into<Ident>, -{ - fn from(ident: T) -> Self { - PathSegment { - ident: ident.into(), - arguments: PathArguments::None, - } - } -} - -ast_enum! { - /// Angle bracketed or parenthesized arguments of a path segment. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - /// - /// ## Angle bracketed - /// - /// The `<'a, T>` in `std::slice::iter<'a, T>`. - /// - /// ## Parenthesized - /// - /// The `(A, B) -> C` in `Fn(A, B) -> C`. - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub enum PathArguments { - None, - /// The `<'a, T>` in `std::slice::iter<'a, T>`. - AngleBracketed(AngleBracketedGenericArguments), - /// The `(A, B) -> C` in `Fn(A, B) -> C`. - Parenthesized(ParenthesizedGenericArguments), - } -} - -impl Default for PathArguments { - fn default() -> Self { - PathArguments::None - } -} - -impl PathArguments { - pub fn is_empty(&self) -> bool { - match self { - PathArguments::None => true, - PathArguments::AngleBracketed(bracketed) => bracketed.args.is_empty(), - PathArguments::Parenthesized(_) => false, - } - } - - pub fn is_none(&self) -> bool { - match self { - PathArguments::None => true, - PathArguments::AngleBracketed(_) | PathArguments::Parenthesized(_) => false, - } - } -} - -ast_enum! { - /// An individual generic argument, like `'a`, `T`, or `Item = T`. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub enum GenericArgument { - /// A lifetime argument. - Lifetime(Lifetime), - /// A type argument. - Type(Type), - /// A const expression. Must be inside of a block. - /// - /// NOTE: Identity expressions are represented as Type arguments, as - /// they are indistinguishable syntactically. - Const(Expr), - /// A binding (equality constraint) on an associated type: the `Item = - /// u8` in `Iterator<Item = u8>`. - Binding(Binding), - /// An associated type bound: `Iterator<Item: Display>`. - Constraint(Constraint), - } -} - -ast_struct! { - /// Angle bracketed arguments of a path segment: the `<K, V>` in `HashMap<K, - /// V>`. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct AngleBracketedGenericArguments { - pub colon2_token: Option<Token![::]>, - pub lt_token: Token![<], - pub args: Punctuated<GenericArgument, Token![,]>, - pub gt_token: Token![>], - } -} - -ast_struct! { - /// A binding (equality constraint) on an associated type: `Item = u8`. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct Binding { - pub ident: Ident, - pub eq_token: Token![=], - pub ty: Type, - } -} - -ast_struct! { - /// An associated type bound: `Iterator<Item: Display>`. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct Constraint { - pub ident: Ident, - pub colon_token: Token![:], - pub bounds: Punctuated<TypeParamBound, Token![+]>, - } -} - -ast_struct! { - /// Arguments of a function path segment: the `(A, B) -> C` in `Fn(A,B) -> - /// C`. - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct ParenthesizedGenericArguments { - pub paren_token: token::Paren, - /// `(A, B)` - pub inputs: Punctuated<Type, Token![,]>, - /// `C` - pub output: ReturnType, - } -} - -ast_struct! { - /// The explicit Self type in a qualified path: the `T` in `<T as - /// Display>::fmt`. - /// - /// The actual path, including the trait and the associated item, is stored - /// separately. The `position` field represents the index of the associated - /// item qualified with this Self type. - /// - /// ```text - /// <Vec<T> as a::b::Trait>::AssociatedItem - /// ^~~~~~ ~~~~~~~~~~~~~~^ - /// ty position = 3 - /// - /// <Vec<T>>::AssociatedItem - /// ^~~~~~ ^ - /// ty position = 0 - /// ``` - /// - /// *This type is available only if Syn is built with the `"derive"` or `"full"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))] - pub struct QSelf { - pub lt_token: Token![<], - pub ty: Box<Type>, - pub position: usize, - pub as_token: Option<Token![as]>, - pub gt_token: Token![>], - } -} - -#[cfg(feature = "parsing")] -pub mod parsing { - use super::*; - - use crate::ext::IdentExt; - use crate::parse::{Parse, ParseStream, Result}; - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for Path { - fn parse(input: ParseStream) -> Result<Self> { - Self::parse_helper(input, false) - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for GenericArgument { - fn parse(input: ParseStream) -> Result<Self> { - if input.peek(Lifetime) && !input.peek2(Token![+]) { - return Ok(GenericArgument::Lifetime(input.parse()?)); - } - - if input.peek(Ident) && input.peek2(Token![=]) { - let ident: Ident = input.parse()?; - let eq_token: Token![=] = input.parse()?; - - let ty = if input.peek(Lit) { - let begin = input.fork(); - input.parse::<Lit>()?; - Type::Verbatim(verbatim::between(begin, input)) - } else if input.peek(token::Brace) { - let begin = input.fork(); - - #[cfg(feature = "full")] - { - input.parse::<ExprBlock>()?; - } - - #[cfg(not(feature = "full"))] - { - let content; - braced!(content in input); - content.parse::<Expr>()?; - } - - Type::Verbatim(verbatim::between(begin, input)) - } else { - input.parse()? - }; - - return Ok(GenericArgument::Binding(Binding { - ident, - eq_token, - ty, - })); - } - - #[cfg(feature = "full")] - { - if input.peek(Ident) && input.peek2(Token![:]) && !input.peek2(Token![::]) { - return Ok(GenericArgument::Constraint(input.parse()?)); - } - } - - if input.peek(Lit) || input.peek(token::Brace) { - return const_argument(input).map(GenericArgument::Const); - } - - #[cfg(feature = "full")] - let begin = input.fork(); - - let argument: Type = input.parse()?; - - #[cfg(feature = "full")] - { - if match &argument { - Type::Path(argument) - if argument.qself.is_none() - && argument.path.leading_colon.is_none() - && argument.path.segments.len() == 1 => - { - match argument.path.segments[0].arguments { - PathArguments::AngleBracketed(_) => true, - _ => false, - } - } - _ => false, - } && if input.peek(Token![=]) { - input.parse::<Token![=]>()?; - input.parse::<Type>()?; - true - } else if input.peek(Token![:]) { - input.parse::<Token![:]>()?; - input.call(constraint_bounds)?; - true - } else { - false - } { - let verbatim = verbatim::between(begin, input); - return Ok(GenericArgument::Type(Type::Verbatim(verbatim))); - } - } - - Ok(GenericArgument::Type(argument)) - } - } - - pub fn const_argument(input: ParseStream) -> Result<Expr> { - let lookahead = input.lookahead1(); - - if input.peek(Lit) { - let lit = input.parse()?; - return Ok(Expr::Lit(lit)); - } - - #[cfg(feature = "full")] - { - if input.peek(Ident) { - let ident: Ident = input.parse()?; - return Ok(Expr::Path(ExprPath { - attrs: Vec::new(), - qself: None, - path: Path::from(ident), - })); - } - } - - if input.peek(token::Brace) { - #[cfg(feature = "full")] - { - let block: ExprBlock = input.parse()?; - return Ok(Expr::Block(block)); - } - - #[cfg(not(feature = "full"))] - { - let begin = input.fork(); - let content; - braced!(content in input); - content.parse::<Expr>()?; - let verbatim = verbatim::between(begin, input); - return Ok(Expr::Verbatim(verbatim)); - } - } - - Err(lookahead.error()) - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for AngleBracketedGenericArguments { - fn parse(input: ParseStream) -> Result<Self> { - Ok(AngleBracketedGenericArguments { - colon2_token: input.parse()?, - lt_token: input.parse()?, - args: { - let mut args = Punctuated::new(); - loop { - if input.peek(Token![>]) { - break; - } - let value = input.parse()?; - args.push_value(value); - if input.peek(Token![>]) { - break; - } - let punct = input.parse()?; - args.push_punct(punct); - } - args - }, - gt_token: input.parse()?, - }) - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for ParenthesizedGenericArguments { - fn parse(input: ParseStream) -> Result<Self> { - let content; - Ok(ParenthesizedGenericArguments { - paren_token: parenthesized!(content in input), - inputs: content.parse_terminated(Type::parse)?, - output: input.call(ReturnType::without_plus)?, - }) - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for PathSegment { - fn parse(input: ParseStream) -> Result<Self> { - Self::parse_helper(input, false) - } - } - - impl PathSegment { - fn parse_helper(input: ParseStream, expr_style: bool) -> Result<Self> { - if input.peek(Token![super]) || input.peek(Token![self]) || input.peek(Token![crate]) { - let ident = input.call(Ident::parse_any)?; - return Ok(PathSegment::from(ident)); - } - - let ident = if input.peek(Token![Self]) { - input.call(Ident::parse_any)? - } else { - input.parse()? - }; - - if !expr_style && input.peek(Token![<]) && !input.peek(Token![<=]) - || input.peek(Token![::]) && input.peek3(Token![<]) - { - Ok(PathSegment { - ident, - arguments: PathArguments::AngleBracketed(input.parse()?), - }) - } else { - Ok(PathSegment::from(ident)) - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for Binding { - fn parse(input: ParseStream) -> Result<Self> { - Ok(Binding { - ident: input.parse()?, - eq_token: input.parse()?, - ty: input.parse()?, - }) - } - } - - #[cfg(feature = "full")] - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - impl Parse for Constraint { - fn parse(input: ParseStream) -> Result<Self> { - Ok(Constraint { - ident: input.parse()?, - colon_token: input.parse()?, - bounds: constraint_bounds(input)?, - }) - } - } - - #[cfg(feature = "full")] - fn constraint_bounds(input: ParseStream) -> Result<Punctuated<TypeParamBound, Token![+]>> { - let mut bounds = Punctuated::new(); - loop { - if input.peek(Token![,]) || input.peek(Token![>]) { - break; - } - let value = input.parse()?; - bounds.push_value(value); - if !input.peek(Token![+]) { - break; - } - let punct = input.parse()?; - bounds.push_punct(punct); - } - Ok(bounds) - } - - impl Path { - /// Parse a `Path` containing no path arguments on any of its segments. - /// - /// *This function is available only if Syn is built with the `"parsing"` - /// feature.* - /// - /// # Example - /// - /// ``` - /// use syn::{Path, Result, Token}; - /// use syn::parse::{Parse, ParseStream}; - /// - /// // A simplified single `use` statement like: - /// // - /// // use std::collections::HashMap; - /// // - /// // Note that generic parameters are not allowed in a `use` statement - /// // so the following must not be accepted. - /// // - /// // use a::<b>::c; - /// struct SingleUse { - /// use_token: Token![use], - /// path: Path, - /// } - /// - /// impl Parse for SingleUse { - /// fn parse(input: ParseStream) -> Result<Self> { - /// Ok(SingleUse { - /// use_token: input.parse()?, - /// path: input.call(Path::parse_mod_style)?, - /// }) - /// } - /// } - /// ``` - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - pub fn parse_mod_style(input: ParseStream) -> Result<Self> { - Ok(Path { - leading_colon: input.parse()?, - segments: { - let mut segments = Punctuated::new(); - loop { - if !input.peek(Ident) - && !input.peek(Token![super]) - && !input.peek(Token![self]) - && !input.peek(Token![Self]) - && !input.peek(Token![crate]) - { - break; - } - let ident = Ident::parse_any(input)?; - segments.push_value(PathSegment::from(ident)); - if !input.peek(Token![::]) { - break; - } - let punct = input.parse()?; - segments.push_punct(punct); - } - if segments.is_empty() { - return Err(input.error("expected path")); - } else if segments.trailing_punct() { - return Err(input.error("expected path segment")); - } - segments - }, - }) - } - - /// Determines whether this is a path of length 1 equal to the given - /// ident. - /// - /// For them to compare equal, it must be the case that: - /// - /// - the path has no leading colon, - /// - the number of path segments is 1, - /// - the first path segment has no angle bracketed or parenthesized - /// path arguments, and - /// - the ident of the first path segment is equal to the given one. - /// - /// *This function is available only if Syn is built with the `"parsing"` - /// feature.* - /// - /// # Example - /// - /// ``` - /// use syn::{Attribute, Error, Meta, NestedMeta, Result}; - /// # use std::iter::FromIterator; - /// - /// fn get_serde_meta_items(attr: &Attribute) -> Result<Vec<NestedMeta>> { - /// if attr.path.is_ident("serde") { - /// match attr.parse_meta()? { - /// Meta::List(meta) => Ok(Vec::from_iter(meta.nested)), - /// bad => Err(Error::new_spanned(bad, "unrecognized attribute")), - /// } - /// } else { - /// Ok(Vec::new()) - /// } - /// } - /// ``` - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - pub fn is_ident<I: ?Sized>(&self, ident: &I) -> bool - where - Ident: PartialEq<I>, - { - match self.get_ident() { - Some(id) => id == ident, - None => false, - } - } - - /// If this path consists of a single ident, returns the ident. - /// - /// A path is considered an ident if: - /// - /// - the path has no leading colon, - /// - the number of path segments is 1, and - /// - the first path segment has no angle bracketed or parenthesized - /// path arguments. - /// - /// *This function is available only if Syn is built with the `"parsing"` - /// feature.* - #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))] - pub fn get_ident(&self) -> Option<&Ident> { - if self.leading_colon.is_none() - && self.segments.len() == 1 - && self.segments[0].arguments.is_none() - { - Some(&self.segments[0].ident) - } else { - None - } - } - - pub(crate) fn parse_helper(input: ParseStream, expr_style: bool) -> Result<Self> { - let mut path = Path { - leading_colon: input.parse()?, - segments: { - let mut segments = Punctuated::new(); - let value = PathSegment::parse_helper(input, expr_style)?; - segments.push_value(value); - segments - }, - }; - Path::parse_rest(input, &mut path, expr_style)?; - Ok(path) - } - - pub(crate) fn parse_rest( - input: ParseStream, - path: &mut Self, - expr_style: bool, - ) -> Result<()> { - while input.peek(Token![::]) && !input.peek3(token::Paren) { - let punct: Token![::] = input.parse()?; - path.segments.push_punct(punct); - let value = PathSegment::parse_helper(input, expr_style)?; - path.segments.push_value(value); - } - Ok(()) - } - } - - pub fn qpath(input: ParseStream, expr_style: bool) -> Result<(Option<QSelf>, Path)> { - if input.peek(Token![<]) { - let lt_token: Token![<] = input.parse()?; - let this: Type = input.parse()?; - let path = if input.peek(Token![as]) { - let as_token: Token![as] = input.parse()?; - let path: Path = input.parse()?; - Some((as_token, path)) - } else { - None - }; - let gt_token: Token![>] = input.parse()?; - let colon2_token: Token![::] = input.parse()?; - let mut rest = Punctuated::new(); - loop { - let path = PathSegment::parse_helper(input, expr_style)?; - rest.push_value(path); - if !input.peek(Token![::]) { - break; - } - let punct: Token![::] = input.parse()?; - rest.push_punct(punct); - } - let (position, as_token, path) = match path { - Some((as_token, mut path)) => { - let pos = path.segments.len(); - path.segments.push_punct(colon2_token); - path.segments.extend(rest.into_pairs()); - (pos, Some(as_token), path) - } - None => { - let path = Path { - leading_colon: Some(colon2_token), - segments: rest, - }; - (0, None, path) - } - }; - let qself = QSelf { - lt_token, - ty: Box::new(this), - position, - as_token, - gt_token, - }; - Ok((Some(qself), path)) - } else { - let path = Path::parse_helper(input, expr_style)?; - Ok((None, path)) - } - } -} - -#[cfg(feature = "printing")] -pub(crate) mod printing { - use super::*; - use crate::print::TokensOrDefault; - use proc_macro2::TokenStream; - use quote::ToTokens; - use std::cmp; - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for Path { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.leading_colon.to_tokens(tokens); - self.segments.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for PathSegment { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.ident.to_tokens(tokens); - self.arguments.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for PathArguments { - fn to_tokens(&self, tokens: &mut TokenStream) { - match self { - PathArguments::None => {} - PathArguments::AngleBracketed(arguments) => { - arguments.to_tokens(tokens); - } - PathArguments::Parenthesized(arguments) => { - arguments.to_tokens(tokens); - } - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for GenericArgument { - #[allow(clippy::match_same_arms)] - fn to_tokens(&self, tokens: &mut TokenStream) { - match self { - GenericArgument::Lifetime(lt) => lt.to_tokens(tokens), - GenericArgument::Type(ty) => ty.to_tokens(tokens), - GenericArgument::Const(e) => match *e { - Expr::Lit(_) => e.to_tokens(tokens), - - // NOTE: We should probably support parsing blocks with only - // expressions in them without the full feature for const - // generics. - #[cfg(feature = "full")] - Expr::Block(_) => e.to_tokens(tokens), - - // ERROR CORRECTION: Add braces to make sure that the - // generated code is valid. - _ => token::Brace::default().surround(tokens, |tokens| { - e.to_tokens(tokens); - }), - }, - GenericArgument::Binding(tb) => tb.to_tokens(tokens), - GenericArgument::Constraint(tc) => tc.to_tokens(tokens), - } - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for AngleBracketedGenericArguments { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.colon2_token.to_tokens(tokens); - self.lt_token.to_tokens(tokens); - - // Print lifetimes before types/consts/bindings, regardless of their - // order in self.args. - let mut trailing_or_empty = true; - for param in self.args.pairs() { - match **param.value() { - GenericArgument::Lifetime(_) => { - param.to_tokens(tokens); - trailing_or_empty = param.punct().is_some(); - } - GenericArgument::Type(_) - | GenericArgument::Const(_) - | GenericArgument::Binding(_) - | GenericArgument::Constraint(_) => {} - } - } - for param in self.args.pairs() { - match **param.value() { - GenericArgument::Type(_) - | GenericArgument::Const(_) - | GenericArgument::Binding(_) - | GenericArgument::Constraint(_) => { - if !trailing_or_empty { - <Token![,]>::default().to_tokens(tokens); - } - param.to_tokens(tokens); - trailing_or_empty = param.punct().is_some(); - } - GenericArgument::Lifetime(_) => {} - } - } - - self.gt_token.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for Binding { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.ident.to_tokens(tokens); - self.eq_token.to_tokens(tokens); - self.ty.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for Constraint { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.ident.to_tokens(tokens); - self.colon_token.to_tokens(tokens); - self.bounds.to_tokens(tokens); - } - } - - #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))] - impl ToTokens for ParenthesizedGenericArguments { - fn to_tokens(&self, tokens: &mut TokenStream) { - self.paren_token.surround(tokens, |tokens| { - self.inputs.to_tokens(tokens); - }); - self.output.to_tokens(tokens); - } - } - - pub(crate) fn print_path(tokens: &mut TokenStream, qself: &Option<QSelf>, path: &Path) { - let qself = match qself { - Some(qself) => qself, - None => { - path.to_tokens(tokens); - return; - } - }; - qself.lt_token.to_tokens(tokens); - qself.ty.to_tokens(tokens); - - let pos = cmp::min(qself.position, path.segments.len()); - let mut segments = path.segments.pairs(); - if pos > 0 { - TokensOrDefault(&qself.as_token).to_tokens(tokens); - path.leading_colon.to_tokens(tokens); - for (i, segment) in segments.by_ref().take(pos).enumerate() { - if i + 1 == pos { - segment.value().to_tokens(tokens); - qself.gt_token.to_tokens(tokens); - segment.punct().to_tokens(tokens); - } else { - segment.to_tokens(tokens); - } - } - } else { - qself.gt_token.to_tokens(tokens); - path.leading_colon.to_tokens(tokens); - } - for segment in segments { - segment.to_tokens(tokens); - } - } -} |