--- /dev/null
+use super::*;
+use crate::punctuated::Punctuated;
+
+ast_struct! {
+ /// An enum variant.
+ ///
+ /// *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 Variant {
+ /// Attributes tagged on the variant.
+ pub attrs: Vec<Attribute>,
+
+ /// Name of the variant.
+ pub ident: Ident,
+
+ /// Content stored in the variant.
+ pub fields: Fields,
+
+ /// Explicit discriminant: `Variant = 1`
+ pub discriminant: Option<(Token![=], Expr)>,
+ }
+}
+
+ast_enum_of_structs! {
+ /// Data stored within an enum variant or struct.
+ ///
+ /// *This type is available only if Syn is built with the `"derive"` or `"full"`
+ /// feature.*
+ ///
+ /// # Syntax tree enum
+ ///
+ /// This type is a [syntax tree enum].
+ ///
+ /// [syntax tree enum]: Expr#syntax-tree-enums
+ #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))]
+ pub enum Fields {
+ /// Named fields of a struct or struct variant such as `Point { x: f64,
+ /// y: f64 }`.
+ Named(FieldsNamed),
+
+ /// Unnamed fields of a tuple struct or tuple variant such as `Some(T)`.
+ Unnamed(FieldsUnnamed),
+
+ /// Unit struct or unit variant such as `None`.
+ Unit,
+ }
+}
+
+ast_struct! {
+ /// Named fields of a struct or struct variant such as `Point { x: f64,
+ /// y: f64 }`.
+ ///
+ /// *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 FieldsNamed {
+ pub brace_token: token::Brace,
+ pub named: Punctuated<Field, Token![,]>,
+ }
+}
+
+ast_struct! {
+ /// Unnamed fields of a tuple struct or tuple variant such as `Some(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 struct FieldsUnnamed {
+ pub paren_token: token::Paren,
+ pub unnamed: Punctuated<Field, Token![,]>,
+ }
+}
+
+impl Fields {
+ /// Get an iterator over the borrowed [`Field`] items in this object. This
+ /// iterator can be used to iterate over a named or unnamed struct or
+ /// variant's fields uniformly.
+ pub fn iter(&self) -> punctuated::Iter<Field> {
+ match self {
+ Fields::Unit => crate::punctuated::empty_punctuated_iter(),
+ Fields::Named(f) => f.named.iter(),
+ Fields::Unnamed(f) => f.unnamed.iter(),
+ }
+ }
+
+ /// Get an iterator over the mutably borrowed [`Field`] items in this
+ /// object. This iterator can be used to iterate over a named or unnamed
+ /// struct or variant's fields uniformly.
+ pub fn iter_mut(&mut self) -> punctuated::IterMut<Field> {
+ match self {
+ Fields::Unit => crate::punctuated::empty_punctuated_iter_mut(),
+ Fields::Named(f) => f.named.iter_mut(),
+ Fields::Unnamed(f) => f.unnamed.iter_mut(),
+ }
+ }
+
+ /// Returns the number of fields.
+ pub fn len(&self) -> usize {
+ match self {
+ Fields::Unit => 0,
+ Fields::Named(f) => f.named.len(),
+ Fields::Unnamed(f) => f.unnamed.len(),
+ }
+ }
+
+ /// Returns `true` if there are zero fields.
+ pub fn is_empty(&self) -> bool {
+ match self {
+ Fields::Unit => true,
+ Fields::Named(f) => f.named.is_empty(),
+ Fields::Unnamed(f) => f.unnamed.is_empty(),
+ }
+ }
+}
+
+impl IntoIterator for Fields {
+ type Item = Field;
+ type IntoIter = punctuated::IntoIter<Field>;
+
+ fn into_iter(self) -> Self::IntoIter {
+ match self {
+ Fields::Unit => Punctuated::<Field, ()>::new().into_iter(),
+ Fields::Named(f) => f.named.into_iter(),
+ Fields::Unnamed(f) => f.unnamed.into_iter(),
+ }
+ }
+}
+
+impl<'a> IntoIterator for &'a Fields {
+ type Item = &'a Field;
+ type IntoIter = punctuated::Iter<'a, Field>;
+
+ fn into_iter(self) -> Self::IntoIter {
+ self.iter()
+ }
+}
+
+impl<'a> IntoIterator for &'a mut Fields {
+ type Item = &'a mut Field;
+ type IntoIter = punctuated::IterMut<'a, Field>;
+
+ fn into_iter(self) -> Self::IntoIter {
+ self.iter_mut()
+ }
+}
+
+ast_struct! {
+ /// A field of a struct or enum variant.
+ ///
+ /// *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 Field {
+ /// Attributes tagged on the field.
+ pub attrs: Vec<Attribute>,
+
+ /// Visibility of the field.
+ pub vis: Visibility,
+
+ /// Name of the field, if any.
+ ///
+ /// Fields of tuple structs have no names.
+ pub ident: Option<Ident>,
+
+ pub colon_token: Option<Token![:]>,
+
+ /// Type of the field.
+ pub ty: Type,
+ }
+}
+
+ast_enum_of_structs! {
+ /// The visibility level of an item: inherited or `pub` or
+ /// `pub(restricted)`.
+ ///
+ /// *This type is available only if Syn is built with the `"derive"` or `"full"`
+ /// feature.*
+ ///
+ /// # Syntax tree enum
+ ///
+ /// This type is a [syntax tree enum].
+ ///
+ /// [syntax tree enum]: Expr#syntax-tree-enums
+ #[cfg_attr(doc_cfg, doc(cfg(any(feature = "full", feature = "derive"))))]
+ pub enum Visibility {
+ /// A public visibility level: `pub`.
+ Public(VisPublic),
+
+ /// A crate-level visibility: `crate`.
+ Crate(VisCrate),
+
+ /// A visibility level restricted to some path: `pub(self)` or
+ /// `pub(super)` or `pub(crate)` or `pub(in some::module)`.
+ Restricted(VisRestricted),
+
+ /// An inherited visibility, which usually means private.
+ Inherited,
+ }
+}
+
+ast_struct! {
+ /// A public visibility level: `pub`.
+ ///
+ /// *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 VisPublic {
+ pub pub_token: Token![pub],
+ }
+}
+
+ast_struct! {
+ /// A crate-level visibility: `crate`.
+ ///
+ /// *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 VisCrate {
+ pub crate_token: Token![crate],
+ }
+}
+
+ast_struct! {
+ /// A visibility level restricted to some path: `pub(self)` or
+ /// `pub(super)` or `pub(crate)` or `pub(in some::module)`.
+ ///
+ /// *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 VisRestricted {
+ pub pub_token: Token![pub],
+ pub paren_token: token::Paren,
+ pub in_token: Option<Token![in]>,
+ pub path: Box<Path>,
+ }
+}
+
+#[cfg(feature = "parsing")]
+pub mod parsing {
+ use super::*;
+ use crate::ext::IdentExt;
+ use crate::parse::discouraged::Speculative;
+ use crate::parse::{Parse, ParseStream, Result};
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
+ impl Parse for Variant {
+ fn parse(input: ParseStream) -> Result<Self> {
+ let attrs = input.call(Attribute::parse_outer)?;
+ let _visibility: Visibility = input.parse()?;
+ let ident: Ident = input.parse()?;
+ let fields = if input.peek(token::Brace) {
+ Fields::Named(input.parse()?)
+ } else if input.peek(token::Paren) {
+ Fields::Unnamed(input.parse()?)
+ } else {
+ Fields::Unit
+ };
+ let discriminant = if input.peek(Token![=]) {
+ let eq_token: Token![=] = input.parse()?;
+ let discriminant: Expr = input.parse()?;
+ Some((eq_token, discriminant))
+ } else {
+ None
+ };
+ Ok(Variant {
+ attrs,
+ ident,
+ fields,
+ discriminant,
+ })
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
+ impl Parse for FieldsNamed {
+ fn parse(input: ParseStream) -> Result<Self> {
+ let content;
+ Ok(FieldsNamed {
+ brace_token: braced!(content in input),
+ named: content.parse_terminated(Field::parse_named)?,
+ })
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
+ impl Parse for FieldsUnnamed {
+ fn parse(input: ParseStream) -> Result<Self> {
+ let content;
+ Ok(FieldsUnnamed {
+ paren_token: parenthesized!(content in input),
+ unnamed: content.parse_terminated(Field::parse_unnamed)?,
+ })
+ }
+ }
+
+ impl Field {
+ /// Parses a named (braced struct) field.
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
+ pub fn parse_named(input: ParseStream) -> Result<Self> {
+ Ok(Field {
+ attrs: input.call(Attribute::parse_outer)?,
+ vis: input.parse()?,
+ ident: Some(if input.peek(Token![_]) {
+ input.call(Ident::parse_any)
+ } else {
+ input.parse()
+ }?),
+ colon_token: Some(input.parse()?),
+ ty: input.parse()?,
+ })
+ }
+
+ /// Parses an unnamed (tuple struct) field.
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
+ pub fn parse_unnamed(input: ParseStream) -> Result<Self> {
+ Ok(Field {
+ attrs: input.call(Attribute::parse_outer)?,
+ vis: input.parse()?,
+ ident: None,
+ colon_token: None,
+ ty: input.parse()?,
+ })
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "parsing")))]
+ impl Parse for Visibility {
+ fn parse(input: ParseStream) -> Result<Self> {
+ // Recognize an empty None-delimited group, as produced by a $:vis
+ // matcher that matched no tokens.
+ if input.peek(token::Group) {
+ let ahead = input.fork();
+ let group = crate::group::parse_group(&ahead)?;
+ if group.content.is_empty() {
+ input.advance_to(&ahead);
+ return Ok(Visibility::Inherited);
+ }
+ }
+
+ if input.peek(Token![pub]) {
+ Self::parse_pub(input)
+ } else if input.peek(Token![crate]) {
+ Self::parse_crate(input)
+ } else {
+ Ok(Visibility::Inherited)
+ }
+ }
+ }
+
+ impl Visibility {
+ fn parse_pub(input: ParseStream) -> Result<Self> {
+ let pub_token = input.parse::<Token![pub]>()?;
+
+ if input.peek(token::Paren) {
+ let ahead = input.fork();
+
+ let content;
+ let paren_token = parenthesized!(content in ahead);
+ if content.peek(Token![crate])
+ || content.peek(Token![self])
+ || content.peek(Token![super])
+ {
+ let path = content.call(Ident::parse_any)?;
+
+ // Ensure there are no additional tokens within `content`.
+ // Without explicitly checking, we may misinterpret a tuple
+ // field as a restricted visibility, causing a parse error.
+ // e.g. `pub (crate::A, crate::B)` (Issue #720).
+ if content.is_empty() {
+ input.advance_to(&ahead);
+ return Ok(Visibility::Restricted(VisRestricted {
+ pub_token,
+ paren_token,
+ in_token: None,
+ path: Box::new(Path::from(path)),
+ }));
+ }
+ } else if content.peek(Token![in]) {
+ let in_token: Token![in] = content.parse()?;
+ let path = content.call(Path::parse_mod_style)?;
+
+ input.advance_to(&ahead);
+ return Ok(Visibility::Restricted(VisRestricted {
+ pub_token,
+ paren_token,
+ in_token: Some(in_token),
+ path: Box::new(path),
+ }));
+ }
+ }
+
+ Ok(Visibility::Public(VisPublic { pub_token }))
+ }
+
+ fn parse_crate(input: ParseStream) -> Result<Self> {
+ if input.peek2(Token![::]) {
+ Ok(Visibility::Inherited)
+ } else {
+ Ok(Visibility::Crate(VisCrate {
+ crate_token: input.parse()?,
+ }))
+ }
+ }
+
+ #[cfg(feature = "full")]
+ pub(crate) fn is_some(&self) -> bool {
+ match self {
+ Visibility::Inherited => false,
+ _ => true,
+ }
+ }
+ }
+}
+
+#[cfg(feature = "printing")]
+mod printing {
+ use super::*;
+ use crate::print::TokensOrDefault;
+ use proc_macro2::TokenStream;
+ use quote::{ToTokens, TokenStreamExt};
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for Variant {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ tokens.append_all(&self.attrs);
+ self.ident.to_tokens(tokens);
+ self.fields.to_tokens(tokens);
+ if let Some((eq_token, disc)) = &self.discriminant {
+ eq_token.to_tokens(tokens);
+ disc.to_tokens(tokens);
+ }
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for FieldsNamed {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ self.brace_token.surround(tokens, |tokens| {
+ self.named.to_tokens(tokens);
+ });
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for FieldsUnnamed {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ self.paren_token.surround(tokens, |tokens| {
+ self.unnamed.to_tokens(tokens);
+ });
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for Field {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ tokens.append_all(&self.attrs);
+ self.vis.to_tokens(tokens);
+ if let Some(ident) = &self.ident {
+ ident.to_tokens(tokens);
+ TokensOrDefault(&self.colon_token).to_tokens(tokens);
+ }
+ self.ty.to_tokens(tokens);
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for VisPublic {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ self.pub_token.to_tokens(tokens);
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for VisCrate {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ self.crate_token.to_tokens(tokens);
+ }
+ }
+
+ #[cfg_attr(doc_cfg, doc(cfg(feature = "printing")))]
+ impl ToTokens for VisRestricted {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ self.pub_token.to_tokens(tokens);
+ self.paren_token.surround(tokens, |tokens| {
+ // TODO: If we have a path which is not "self" or "super" or
+ // "crate", automatically add the "in" token.
+ self.in_token.to_tokens(tokens);
+ self.path.to_tokens(tokens);
+ });
+ }
+ }
+}
projects / rustc.git / blobdiff