diff options
Diffstat (limited to 'src/libsyntax/parse')
| -rw-r--r-- | src/libsyntax/parse/parser.rs | 96 | ||||
| -rw-r--r-- | src/libsyntax/parse/parser/item.rs | 55 | ||||
| -rw-r--r-- | src/libsyntax/parse/parser/ty.rs | 14 |
3 files changed, 74 insertions, 91 deletions
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 93165b09649..4a457f5a43c 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -11,7 +11,7 @@ mod stmt; mod generics; use crate::ast::{ - self, DUMMY_NODE_ID, AttrStyle, Attribute, BindingMode, CrateSugar, FnDecl, Ident, + self, DUMMY_NODE_ID, AttrStyle, Attribute, BindingMode, CrateSugar, Ident, IsAsync, MacDelimiter, Mutability, Param, StrStyle, SelfKind, TyKind, Visibility, VisibilityKind, Unsafety, }; @@ -56,6 +56,17 @@ crate enum BlockMode { Ignore, } +/// The parsing configuration used to parse a parameter list (see `parse_fn_params`). +struct ParamCfg { + /// Is `self` is allowed as the first parameter? + is_self_allowed: bool, + /// Is `...` allowed as the tail of the parameter list? + allow_c_variadic: bool, + /// `is_name_required` decides if, per-parameter, + /// the parameter must have a pattern or just a type. + is_name_required: fn(&token::Token) -> bool, +} + /// Like `maybe_whole_expr`, but for things other than expressions. #[macro_export] macro_rules! maybe_whole { @@ -1094,26 +1105,18 @@ impl<'a> Parser<'a> { res } - fn parse_fn_params( - &mut self, - named_params: bool, - allow_c_variadic: bool, - ) -> PResult<'a, Vec<Param>> { + /// Parses the parameter list of a function, including the `(` and `)` delimiters. + fn parse_fn_params(&mut self, mut cfg: ParamCfg) -> PResult<'a, Vec<Param>> { let sp = self.token.span; - let do_not_enforce_named_params_for_c_variadic = |token: &token::Token| { - match token.kind { - token::DotDotDot => false, - _ => named_params, - } - }; + let is_trait_item = cfg.is_self_allowed; let mut c_variadic = false; + // Parse the arguments, starting out with `self` being possibly allowed... let (params, _) = self.parse_paren_comma_seq(|p| { - match p.parse_param_general( - false, - false, - allow_c_variadic, - do_not_enforce_named_params_for_c_variadic, - ) { + let param = p.parse_param_general(&cfg, is_trait_item); + // ...now that we've parsed the first argument, `self` is no longer allowed. + cfg.is_self_allowed = false; + + match param { Ok(param) => Ok( if let TyKind::CVarArgs = param.ty.kind { c_variadic = true; @@ -1144,7 +1147,10 @@ impl<'a> Parser<'a> { } })?; - let params: Vec<_> = params.into_iter().filter_map(|x| x).collect(); + let mut params: Vec<_> = params.into_iter().filter_map(|x| x).collect(); + + // Replace duplicated recovered params with `_` pattern to avoid unecessary errors. + self.deduplicate_recovered_params_names(&mut params); if c_variadic && params.len() <= 1 { self.span_err( @@ -1156,79 +1162,53 @@ impl<'a> Parser<'a> { Ok(params) } - /// Parses the parameter list and result type of a function that may have a `self` parameter. - fn parse_fn_decl_with_self( - &mut self, - is_name_required: impl Copy + Fn(&token::Token) -> bool, - ) -> PResult<'a, P<FnDecl>> { - // Parse the arguments, starting out with `self` being allowed... - let mut is_self_allowed = true; - let (mut inputs, _): (Vec<_>, _) = self.parse_paren_comma_seq(|p| { - let res = p.parse_param_general(is_self_allowed, true, false, is_name_required); - // ...but now that we've parsed the first argument, `self` is no longer allowed. - is_self_allowed = false; - res - })?; - - // Replace duplicated recovered params with `_` pattern to avoid unecessary errors. - self.deduplicate_recovered_params_names(&mut inputs); - - Ok(P(FnDecl { - inputs, - output: self.parse_ret_ty(true)?, - })) - } - /// Skips unexpected attributes and doc comments in this position and emits an appropriate /// error. /// This version of parse param doesn't necessarily require identifier names. - fn parse_param_general( - &mut self, - is_self_allowed: bool, - is_trait_item: bool, - allow_c_variadic: bool, - is_name_required: impl Fn(&token::Token) -> bool, - ) -> PResult<'a, Param> { + fn parse_param_general(&mut self, cfg: &ParamCfg, is_trait_item: bool) -> PResult<'a, Param> { let lo = self.token.span; let attrs = self.parse_outer_attributes()?; // Possibly parse `self`. Recover if we parsed it and it wasn't allowed here. if let Some(mut param) = self.parse_self_param()? { param.attrs = attrs.into(); - return if is_self_allowed { + return if cfg.is_self_allowed { Ok(param) } else { self.recover_bad_self_param(param, is_trait_item) }; } - let is_name_required = is_name_required(&self.token); + let is_name_required = match self.token.kind { + token::DotDotDot => false, + _ => (cfg.is_name_required)(&self.token), + }; let (pat, ty) = if is_name_required || self.is_named_param() { debug!("parse_param_general parse_pat (is_name_required:{})", is_name_required); let pat = self.parse_fn_param_pat()?; if let Err(mut err) = self.expect(&token::Colon) { - if let Some(ident) = self.parameter_without_type( + return if let Some(ident) = self.parameter_without_type( &mut err, pat, is_name_required, - is_self_allowed, + cfg.is_self_allowed, is_trait_item, ) { err.emit(); - return Ok(dummy_arg(ident)); + Ok(dummy_arg(ident)) } else { - return Err(err); - } + Err(err) + }; } self.eat_incorrect_doc_comment_for_param_type(); - (pat, self.parse_ty_common(true, true, allow_c_variadic)?) + (pat, self.parse_ty_common(true, true, cfg.allow_c_variadic)?) } else { debug!("parse_param_general ident_to_pat"); let parser_snapshot_before_ty = self.clone(); self.eat_incorrect_doc_comment_for_param_type(); - let mut ty = self.parse_ty_common(true, true, allow_c_variadic); + let mut ty = self.parse_ty_common(true, true, cfg.allow_c_variadic); if ty.is_ok() && self.token != token::Comma && self.token != token::CloseDelim(token::Paren) { // This wasn't actually a type, but a pattern looking like a type, diff --git a/src/libsyntax/parse/parser/item.rs b/src/libsyntax/parse/parser/item.rs index 17b23651e80..d2ea0829595 100644 --- a/src/libsyntax/parse/parser/item.rs +++ b/src/libsyntax/parse/parser/item.rs @@ -1,4 +1,4 @@ -use super::{Parser, PResult, PathStyle, SemiColonMode, BlockMode}; +use super::{Parser, PResult, PathStyle, SemiColonMode, BlockMode, ParamCfg}; use crate::maybe_whole; use crate::ptr::P; @@ -805,14 +805,15 @@ impl<'a> Parser<'a> { /// of a method. The body is not parsed as that differs between `trait`s and `impl`s. fn parse_method_sig( &mut self, - is_name_required: impl Copy + Fn(&token::Token) -> bool, + is_name_required: fn(&token::Token) -> bool, ) -> PResult<'a, (Ident, MethodSig, Generics)> { let header = self.parse_fn_front_matter()?; - let (ident, mut generics) = self.parse_fn_header()?; - let decl = self.parse_fn_decl_with_self(is_name_required)?; - let sig = MethodSig { header, decl }; - generics.where_clause = self.parse_where_clause()?; - Ok((ident, sig, generics)) + let (ident, decl, generics) = self.parse_fn_sig(ParamCfg { + is_self_allowed: true, + allow_c_variadic: false, + is_name_required, + })?; + Ok((ident, MethodSig { header, decl }, generics)) } /// Parses all the "front matter" for a `fn` declaration, up to @@ -1200,36 +1201,34 @@ impl<'a> Parser<'a> { attrs: Vec<Attribute>, header: FnHeader, ) -> PResult<'a, Option<P<Item>>> { - let allow_c_variadic = header.abi == Abi::C && header.unsafety == Unsafety::Unsafe; - let (ident, decl, generics) = self.parse_fn_sig(allow_c_variadic)?; + let (ident, decl, generics) = self.parse_fn_sig(ParamCfg { + is_self_allowed: false, + allow_c_variadic: header.abi == Abi::C && header.unsafety == Unsafety::Unsafe, + is_name_required: |_| true, + })?; let (inner_attrs, body) = self.parse_inner_attrs_and_block()?; let kind = ItemKind::Fn(decl, header, generics, body); self.mk_item_with_info(attrs, lo, vis, (ident, kind, Some(inner_attrs))) } /// Parse the "signature", including the identifier, parameters, and generics of a function. - fn parse_fn_sig( - &mut self, - allow_c_variadic: bool, - ) -> PResult<'a, (Ident, P<FnDecl>, Generics)> { - let (ident, mut generics) = self.parse_fn_header()?; - let decl = self.parse_fn_decl(allow_c_variadic)?; + fn parse_fn_sig(&mut self, cfg: ParamCfg) -> PResult<'a, (Ident, P<FnDecl>, Generics)> { + let ident = self.parse_ident()?; + let mut generics = self.parse_generics()?; + let decl = self.parse_fn_decl(cfg, true)?; generics.where_clause = self.parse_where_clause()?; Ok((ident, decl, generics)) } - /// Parses the name and optional generic types of a function header. - fn parse_fn_header(&mut self) -> PResult<'a, (Ident, Generics)> { - let id = self.parse_ident()?; - let generics = self.parse_generics()?; - Ok((id, generics)) - } - /// Parses the parameter list and result type of a function declaration. - fn parse_fn_decl(&mut self, allow_c_variadic: bool) -> PResult<'a, P<FnDecl>> { + pub(super) fn parse_fn_decl( + &mut self, + cfg: ParamCfg, + ret_allow_plus: bool, + ) -> PResult<'a, P<FnDecl>> { Ok(P(FnDecl { - inputs: self.parse_fn_params(true, allow_c_variadic)?, - output: self.parse_ret_ty(true)?, + inputs: self.parse_fn_params(cfg)?, + output: self.parse_ret_ty(ret_allow_plus)?, })) } @@ -1353,7 +1352,11 @@ impl<'a> Parser<'a> { extern_sp: Span, ) -> PResult<'a, ForeignItem> { self.expect_keyword(kw::Fn)?; - let (ident, decl, generics) = self.parse_fn_sig(true)?; + let (ident, decl, generics) = self.parse_fn_sig(super::ParamCfg { + is_self_allowed: false, + allow_c_variadic: true, + is_name_required: |_| true, + })?; let span = lo.to(self.token.span); self.parse_semi_or_incorrect_foreign_fn_body(&ident, extern_sp)?; Ok(ast::ForeignItem { diff --git a/src/libsyntax/parse/parser/ty.rs b/src/libsyntax/parse/parser/ty.rs index 41ee2a1599d..c9446a880b0 100644 --- a/src/libsyntax/parse/parser/ty.rs +++ b/src/libsyntax/parse/parser/ty.rs @@ -4,7 +4,7 @@ use crate::{maybe_whole, maybe_recover_from_interpolated_ty_qpath}; use crate::ptr::P; use crate::ast::{self, Ty, TyKind, MutTy, BareFnTy, FunctionRetTy, GenericParam, Lifetime, Ident}; use crate::ast::{TraitBoundModifier, TraitObjectSyntax, GenericBound, GenericBounds, PolyTraitRef}; -use crate::ast::{Mutability, AnonConst, FnDecl, Mac}; +use crate::ast::{Mutability, AnonConst, Mac}; use crate::parse::token::{self, Token}; use crate::source_map::Span; use crate::symbol::{kw}; @@ -288,12 +288,12 @@ impl<'a> Parser<'a> { }; self.expect_keyword(kw::Fn)?; - let inputs = self.parse_fn_params(false, true)?; - let ret_ty = self.parse_ret_ty(false)?; - let decl = P(FnDecl { - inputs, - output: ret_ty, - }); + let cfg = super::ParamCfg { + is_self_allowed: false, + allow_c_variadic: true, + is_name_required: |_| false, + }; + let decl = self.parse_fn_decl(cfg, false)?; Ok(TyKind::BareFn(P(BareFnTy { abi, unsafety, |