Use ForceCollect in parse_attr_item.

Instead of a `bool`. Because `ForceCollect` is used in this way
everywhere else.

compiler/rustc_builtin_macros/src/cmdline_attrs.rs

@@ -4,6 +4,7 @@ use crate::errors;
 use rustc_ast::attr::mk_attr;
 use rustc_ast::token;
 use rustc_ast::{self as ast, AttrItem, AttrStyle};
+use rustc_parse::parser::ForceCollect;
 use rustc_parse::{new_parser_from_source_str, unwrap_or_emit_fatal};
 use rustc_session::parse::ParseSess;
 use rustc_span::FileName;
@@ -17,7 +18,8 @@ pub fn inject(krate: &mut ast::Crate, psess: &ParseSess, attrs: &[String]) {
         ));
 
         let start_span = parser.token.span;
-        let AttrItem { unsafety, path, args, tokens: _ } = match parser.parse_attr_item(false) {
+        let AttrItem { unsafety, path, args, tokens: _ } =
+            match parser.parse_attr_item(ForceCollect::No) {
                 Ok(ai) => ai,
                 Err(err) => {
                     err.emit();

compiler/rustc_parse/src/parser/attr.rs

@@ -124,7 +124,7 @@ impl<'a> Parser<'a> {
                 if this.eat(&token::Not) { ast::AttrStyle::Inner } else { ast::AttrStyle::Outer };
 
             this.expect(&token::OpenDelim(Delimiter::Bracket))?;
-            let item = this.parse_attr_item(false)?;
+            let item = this.parse_attr_item(ForceCollect::No)?;
             this.expect(&token::CloseDelim(Delimiter::Bracket))?;
             let attr_sp = lo.to(this.prev_token.span);
 
@@ -248,7 +248,7 @@ impl<'a> Parser<'a> {
     ///     PATH
     ///     PATH `=` UNSUFFIXED_LIT
     /// The delimiters or `=` are still put into the resulting token stream.
-    pub fn parse_attr_item(&mut self, capture_tokens: bool) -> PResult<'a, ast::AttrItem> {
+    pub fn parse_attr_item(&mut self, force_collect: ForceCollect) -> PResult<'a, ast::AttrItem> {
         maybe_whole!(self, NtMeta, |attr| attr.into_inner());
 
         let do_parse = |this: &mut Self| {
@@ -271,7 +271,10 @@ impl<'a> Parser<'a> {
             Ok(ast::AttrItem { unsafety, path, args, tokens: None })
         };
         // Attr items don't have attributes
-        if capture_tokens { self.collect_tokens_no_attrs(do_parse) } else { do_parse(self) }
+        match force_collect {
+            ForceCollect::Yes => self.collect_tokens_no_attrs(do_parse),
+            ForceCollect::No => do_parse(self),
+        }
     }
 
     /// Parses attributes that appear after the opening of an item. These should
@@ -344,7 +347,7 @@ impl<'a> Parser<'a> {
         let mut expanded_attrs = Vec::with_capacity(1);
         while self.token.kind != token::Eof {
             let lo = self.token.span;
-            let item = self.parse_attr_item(true)?;
+            let item = self.parse_attr_item(ForceCollect::Yes)?;
             expanded_attrs.push((item, lo.to(self.prev_token.span)));
             if !self.eat(&token::Comma) {
                 break;

compiler/rustc_parse/src/parser/nonterminal.rs

@@ -171,7 +171,7 @@ impl<'a> Parser<'a> {
             NonterminalKind::Path => {
                 NtPath(P(self.collect_tokens_no_attrs(|this| this.parse_path(PathStyle::Type))?))
             }
-            NonterminalKind::Meta => NtMeta(P(self.parse_attr_item(true)?)),
+            NonterminalKind::Meta => NtMeta(P(self.parse_attr_item(ForceCollect::Yes)?)),
             NonterminalKind::Vis => {
                 NtVis(P(self
                     .collect_tokens_no_attrs(|this| this.parse_visibility(FollowedByType::Yes))?))