From bfaf4180ae8f048634d270564692d35f64a9c130 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Sat, 24 Mar 2018 19:49:50 +0300
Subject: Make lifetime nonterminals closer to identifier nonterminals

---
 src/libsyntax/parse/parser.rs | 21 +++++++++------
 src/libsyntax/parse/token.rs  | 63 ++++++++++++++++++++-----------------------
 2 files changed, 42 insertions(+), 42 deletions(-)

(limited to 'src/libsyntax/parse')

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 72c1b52ba03..84c770605d5 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -2048,18 +2048,20 @@ impl<'a> Parser<'a> {
 
     /// Parse single lifetime 'a or panic.
     pub fn expect_lifetime(&mut self) -> Lifetime {
-        if let Some(lifetime) = self.token.lifetime2(self.span) {
+        if let Some(ident) = self.token.lifetime() {
+            let span = self.span;
             self.bump();
-            lifetime
+            Lifetime { ident: Ident::new(ident.name, span), id: ast::DUMMY_NODE_ID }
         } else {
             self.span_bug(self.span, "not a lifetime")
         }
     }
 
     fn eat_label(&mut self) -> Option<Label> {
-        if let Some(lifetime) = self.token.lifetime2(self.span) {
+        if let Some(ident) = self.token.lifetime() {
+            let span = self.span;
             self.bump();
-            Some(Label { ident: lifetime.ident })
+            Some(Label { ident: Ident::new(ident.name, span) })
         } else {
             None
         }
@@ -2703,7 +2705,7 @@ impl<'a> Parser<'a> {
     }
 
     pub fn process_potential_macro_variable(&mut self) {
-        let (ident, is_raw) = match self.token {
+        let (token, span) = match self.token {
             token::Dollar if self.span.ctxt() != syntax_pos::hygiene::SyntaxContext::empty() &&
                              self.look_ahead(1, |t| t.is_ident()) => {
                 self.bump();
@@ -2718,15 +2720,18 @@ impl<'a> Parser<'a> {
             }
             token::Interpolated(ref nt) => {
                 self.meta_var_span = Some(self.span);
+                // Interpolated identifier and lifetime tokens are replaced with usual identifier
+                // and lifetime tokens, so the former are never encountered during normal parsing.
                 match nt.0 {
-                    token::NtIdent(ident, is_raw) => (ident, is_raw),
+                    token::NtIdent(ident, is_raw) => (token::Ident(ident, is_raw), ident.span),
+                    token::NtLifetime(ident) => (token::Lifetime(ident), ident.span),
                     _ => return,
                 }
             }
             _ => return,
         };
-        self.token = token::Ident(ident, is_raw);
-        self.span = ident.span;
+        self.token = token;
+        self.span = span;
     }
 
     /// parse a single token tree from the input.
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index c1049beea9f..6544619af9c 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -317,7 +317,8 @@ impl Token {
         }
     }
 
-    pub fn ident(&self) -> Option<(ast::Ident, bool)> {
+    /// Returns an identifier if this token is an identifier.
+    pub fn ident(&self) -> Option<(ast::Ident, /* is_raw */ bool)> {
         match *self {
             Ident(ident, is_raw) => Some((ident, is_raw)),
             Interpolated(ref nt) => match nt.0 {
@@ -327,11 +328,25 @@ impl Token {
             _ => None,
         }
     }
-
+    /// Returns a lifetime identifier if this token is a lifetime.
+    pub fn lifetime(&self) -> Option<ast::Ident> {
+        match *self {
+            Lifetime(ident) => Some(ident),
+            Interpolated(ref nt) => match nt.0 {
+                NtLifetime(ident) => Some(ident),
+                _ => None,
+            },
+            _ => None,
+        }
+    }
     /// Returns `true` if the token is an identifier.
     pub fn is_ident(&self) -> bool {
         self.ident().is_some()
     }
+    /// Returns `true` if the token is a lifetime.
+    pub fn is_lifetime(&self) -> bool {
+        self.lifetime().is_some()
+    }
 
     /// Returns `true` if the token is a documentation comment.
     pub fn is_doc_comment(&self) -> bool {
@@ -359,26 +374,6 @@ impl Token {
         false
     }
 
-    /// Returns a lifetime with the span and a dummy id if it is a lifetime,
-    /// or the original lifetime if it is an interpolated lifetime, ignoring
-    /// the span.
-    pub fn lifetime2(&self, span: Span) -> Option<ast::Lifetime> {
-        match *self {
-            Lifetime(ident) => Some(ast::Lifetime { id: ast::DUMMY_NODE_ID,
-                                                    ident: ast::Ident::new(ident.name, span) }),
-            Interpolated(ref nt) => match nt.0 {
-                NtLifetime(lifetime) => Some(lifetime),
-                _ => None,
-            },
-            _ => None,
-        }
-    }
-
-    /// Returns `true` if the token is a lifetime.
-    pub fn is_lifetime(&self) -> bool {
-        self.lifetime2(syntax_pos::DUMMY_SP).is_some()
-    }
-
     /// Returns `true` if the token is either the `mut` or `const` keyword.
     pub fn is_mutability(&self) -> bool {
         self.is_keyword(keywords::Mut) ||
@@ -431,6 +426,14 @@ impl Token {
         }
     }
 
+    /// Returns `true` if the token is either a special identifier or a keyword.
+    pub fn is_reserved_ident(&self) -> bool {
+        match self.ident() {
+            Some((id, false)) => is_reserved_ident(id),
+            _ => false,
+        }
+    }
+
     pub fn glue(self, joint: Token) -> Option<Token> {
         Some(match self {
             Eq => match joint {
@@ -497,14 +500,6 @@ impl Token {
         }
     }
 
-    /// Returns `true` if the token is either a special identifier or a keyword.
-    pub fn is_reserved_ident(&self) -> bool {
-        match self.ident() {
-            Some((id, false)) => is_reserved_ident(id),
-            _ => false,
-        }
-    }
-
     pub fn interpolated_to_tokenstream(&self, sess: &ParseSess, span: Span)
         -> TokenStream
     {
@@ -542,9 +537,9 @@ impl Token {
                 let token = Token::Ident(ident, is_raw);
                 tokens = Some(TokenTree::Token(ident.span, token).into());
             }
-            Nonterminal::NtLifetime(lifetime) => {
-                let token = Token::Lifetime(lifetime.ident);
-                tokens = Some(TokenTree::Token(lifetime.ident.span, token).into());
+            Nonterminal::NtLifetime(ident) => {
+                let token = Token::Lifetime(ident);
+                tokens = Some(TokenTree::Token(ident.span, token).into());
             }
             Nonterminal::NtTT(ref tt) => {
                 tokens = Some(tt.clone().into());
@@ -572,6 +567,7 @@ pub enum Nonterminal {
     NtExpr(P<ast::Expr>),
     NtTy(P<ast::Ty>),
     NtIdent(ast::Ident, /* is_raw */ bool),
+    NtLifetime(ast::Ident),
     /// Stuff inside brackets for attributes
     NtMeta(ast::MetaItem),
     NtPath(ast::Path),
@@ -585,7 +581,6 @@ pub enum Nonterminal {
     NtGenerics(ast::Generics),
     NtWhereClause(ast::WhereClause),
     NtArg(ast::Arg),
-    NtLifetime(ast::Lifetime),
 }
 
 impl fmt::Debug for Nonterminal {
-- 
cgit 1.4.1-3-g733a5