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Diffstat (limited to 'third_party/rust/syn/src/data.rs')
| -rw-r--r-- | third_party/rust/syn/src/data.rs | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/third_party/rust/syn/src/data.rs b/third_party/rust/syn/src/data.rs new file mode 100644 index 0000000000..3b466618f8 --- /dev/null +++ b/third_party/rust/syn/src/data.rs @@ -0,0 +1,493 @@ +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); + }); + } + } +} |