extract parse_not_expr

11 files changed, 86 insertions, 108 deletions

diff --git a/src/librustc_parse/parser/attr.rs b/src/librustc_parse/parser/attr.rs
index 377d43dec21..0be83e418e3 100644
--- a/src/librustc_parse/parser/attr.rs
+++ b/src/librustc_parse/parser/attr.rs
@@ -1,9 +1,10 @@
 use super::{Parser, PathStyle, TokenType};
 use rustc_errors::PResult;
 use syntax::ast;
-use syntax::attr;
+use syntax::print::pprust;
 use syntax::token::{self, Nonterminal};
 use syntax::util::comments;
+use syntax::util::comments;
 use syntax_pos::{Span, Symbol};
 
 use log::debug;
@@ -154,7 +155,7 @@ impl<'a> Parser<'a> {
                 (attr_sp, item, style)
             }
             _ => {
-                let token_str = self.this_token_to_string();
+                let token_str = pprust::token_to_string(&self.token);
                 return Err(self.fatal(&format!("expected `#`, found `{}`", token_str)));
             }
         };
@@ -329,7 +330,7 @@ impl<'a> Parser<'a> {
             Err(ref mut err) => err.cancel(),
         }
 
-        let found = self.this_token_to_string();
+        let found = pprust::token_to_string(&self.token);
         let msg = format!("expected unsuffixed literal or identifier, found `{}`", found);
         Err(self.diagnostic().struct_span_err(self.token.span, &msg))
     }
diff --git a/src/librustc_parse/parser/diagnostics.rs b/src/librustc_parse/parser/diagnostics.rs
index f58b9a4c144..578f816be58 100644
--- a/src/librustc_parse/parser/diagnostics.rs
+++ b/src/librustc_parse/parser/diagnostics.rs
@@ -200,7 +200,7 @@ impl<'a> Parser<'a> {
     pub(super) fn expected_ident_found(&self) -> DiagnosticBuilder<'a> {
         let mut err = self.struct_span_err(
             self.token.span,
-            &format!("expected identifier, found {}", self.this_token_descr()),
+            &format!("expected identifier, found {}", super::token_descr(&self.token)),
         );
         let valid_follow = &[
             TokenKind::Eq,
@@ -225,7 +225,7 @@ impl<'a> Parser<'a> {
                 );
             }
         }
-        if let Some(token_descr) = self.token_descr() {
+        if let Some(token_descr) = super::token_descr_opt(&self.token) {
             err.span_label(self.token.span, format!("expected identifier, found {}", token_descr));
         } else {
             err.span_label(self.token.span, "expected identifier");
@@ -272,7 +272,7 @@ impl<'a> Parser<'a> {
         expected.sort_by_cached_key(|x| x.to_string());
         expected.dedup();
         let expect = tokens_to_string(&expected[..]);
-        let actual = self.this_token_descr();
+        let actual = super::token_descr(&self.token);
         let (msg_exp, (label_sp, label_exp)) = if expected.len() > 1 {
             let short_expect = if expected.len() > 6 {
                 format!("{} possible tokens", expected.len())
@@ -815,7 +815,7 @@ impl<'a> Parser<'a> {
         t: &TokenKind,
     ) -> PResult<'a, bool /* recovered */> {
         let token_str = pprust::token_kind_to_string(t);
-        let this_token_str = self.this_token_descr();
+        let this_token_str = super::token_descr(&self.token);
         let (prev_sp, sp) = match (&self.token.kind, self.subparser_name) {
             // Point at the end of the macro call when reaching end of macro arguments.
             (token::Eof, Some(_)) => {
@@ -862,7 +862,7 @@ impl<'a> Parser<'a> {
             return Ok(());
         }
         let sm = self.sess.source_map();
-        let msg = format!("expected `;`, found `{}`", self.this_token_descr());
+        let msg = format!("expected `;`, found `{}`", super::token_descr(&self.token));
         let appl = Applicability::MachineApplicable;
         if self.token.span == DUMMY_SP || self.prev_span == DUMMY_SP {
             // Likely inside a macro, can't provide meaninful suggestions.
@@ -1270,7 +1270,7 @@ impl<'a> Parser<'a> {
     }
 
     pub(super) fn expected_semi_or_open_brace<T>(&mut self) -> PResult<'a, T> {
-        let token_str = self.this_token_descr();
+        let token_str = super::token_descr(&self.token);
         let mut err = self.fatal(&format!("expected `;` or `{{`, found {}", token_str));
         err.span_label(self.token.span, "expected `;` or `{`");
         Err(err)
@@ -1447,7 +1447,7 @@ impl<'a> Parser<'a> {
             }
             _ => (
                 self.token.span,
-                format!("expected expression, found {}", self.this_token_descr(),),
+                format!("expected expression, found {}", super::token_descr(&self.token),),
             ),
         };
         let mut err = self.struct_span_err(span, &msg);
diff --git a/src/librustc_parse/parser/expr.rs b/src/librustc_parse/parser/expr.rs
index 606714b5fa2..9b106b6db3c 100644
--- a/src/librustc_parse/parser/expr.rs
+++ b/src/librustc_parse/parser/expr.rs
@@ -442,35 +442,37 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses a prefix-unary-operator expr.
-    fn parse_prefix_expr(&mut self, already_parsed_attrs: Option<AttrVec>) -> PResult<'a, P<Expr>> {
-        let attrs = self.parse_or_use_outer_attributes(already_parsed_attrs)?;
+    fn parse_prefix_expr(&mut self, attrs: Option<AttrVec>) -> PResult<'a, P<Expr>> {
+        let attrs = self.parse_or_use_outer_attributes(attrs)?;
         let lo = self.token.span;
         // Note: when adding new unary operators, don't forget to adjust TokenKind::can_begin_expr()
         let (hi, ex) = match self.token.kind {
-            token::Not => {
-                self.bump();
-                let e = self.parse_prefix_expr(None);
-                let (span, e) = self.interpolated_or_expr_span(e)?;
-                (lo.to(span), self.mk_unary(UnOp::Not, e))
-            }
-            token::Tilde => self.recover_tilde_expr(lo)?,
-            token::BinOp(token::Minus) => self.parse_neg_expr(lo)?,
-            token::BinOp(token::Star) => self.parse_deref_expr(lo)?,
-            token::BinOp(token::And) | token::AndAnd => self.parse_borrow_expr(lo)?,
-            token::Ident(..) if self.token.is_keyword(kw::Box) => self.parse_box_expr(lo)?,
-            token::Ident(..) if self.is_mistaken_not_ident_negation() => {
-                self.recover_not_expr(lo)?
-            }
+            token::Not => self.parse_unary_expr(lo, UnOp::Not), // `!expr`
+            token::Tilde => self.recover_tilde_expr(lo),        // `~expr`
+            token::BinOp(token::Minus) => self.parse_unary_expr(lo, UnOp::Neg), // `-expr`
+            token::BinOp(token::Star) => self.parse_unary_expr(lo, UnOp::Deref), // `*expr`
+            token::BinOp(token::And) | token::AndAnd => self.parse_borrow_expr(lo),
+            token::Ident(..) if self.token.is_keyword(kw::Box) => self.parse_box_expr(lo),
+            token::Ident(..) if self.is_mistaken_not_ident_negation() => self.recover_not_expr(lo),
             _ => return self.parse_dot_or_call_expr(Some(attrs)),
-        };
-        return Ok(self.mk_expr(lo.to(hi), ex, attrs));
+        }?;
+        Ok(self.mk_expr(lo.to(hi), ex, attrs))
     }
 
-    // Recover on `!` suggesting for bitwise negation instead.
-    fn recover_tilde_expr(&mut self, lo: Span) -> PResult<'a, (Span, ExprKind)> {
+    fn parse_prefix_expr_common(&mut self, lo: Span) -> PResult<'a, (Span, P<Expr>)> {
         self.bump();
         let expr = self.parse_prefix_expr(None);
         let (span, expr) = self.interpolated_or_expr_span(expr)?;
+        Ok((lo.to(span), expr))
+    }
+
+    fn parse_unary_expr(&mut self, lo: Span, op: UnOp) -> PResult<'a, (Span, ExprKind)> {
+        let (span, expr) = self.parse_prefix_expr_common(lo)?;
+        Ok((span, self.mk_unary(op, expr)))
+    }
+
+    // Recover on `!` suggesting for bitwise negation instead.
+    fn recover_tilde_expr(&mut self, lo: Span) -> PResult<'a, (Span, ExprKind)> {
         self.struct_span_err(lo, "`~` cannot be used as a unary operator")
             .span_suggestion_short(
                 lo,
@@ -479,31 +481,13 @@ impl<'a> Parser<'a> {
                 Applicability::MachineApplicable,
             )
             .emit();
-        Ok((lo.to(span), self.mk_unary(UnOp::Not, expr)))
-    }
 
-    /// Parse `-expr`.
-    fn parse_neg_expr(&mut self, lo: Span) -> PResult<'a, (Span, ExprKind)> {
-        self.bump(); // `-`
-        let expr = self.parse_prefix_expr(None);
-        let (span, expr) = self.interpolated_or_expr_span(expr)?;
-        Ok((lo.to(span), self.mk_unary(UnOp::Neg, expr)))
-    }
-
-    /// Parse `*expr`.
-    fn parse_deref_expr(&mut self, lo: Span) -> PResult<'a, (Span, ExprKind)> {
-        self.bump(); // `*`
-        let expr = self.parse_prefix_expr(None);
-        let (span, expr) = self.interpolated_or_expr_span(expr)?;
-        Ok((lo.to(span), self.mk_unary(UnOp::Deref, expr)))
+        self.parse_unary_expr(lo, UnOp::Not)
     }
 
     /// Parse `box expr`.
     fn parse_box_expr(&mut self, lo: Span) -> PResult<'a, (Span, ExprKind)> {
-        self.bump(); // `box`
-        let expr = self.parse_prefix_expr(None);
-        let (span, expr) = self.interpolated_or_expr_span(expr)?;
-        let span = lo.to(span);
+        let (span, expr) = self.parse_prefix_expr_common(lo)?;
         self.sess.gated_spans.gate(sym::box_syntax, span);
         Ok((span, ExprKind::Box(expr)))
     }
@@ -521,26 +505,24 @@ impl<'a> Parser<'a> {
 
     /// Recover on `not expr` in favor of `!expr`.
     fn recover_not_expr(&mut self, lo: Span) -> PResult<'a, (Span, ExprKind)> {
-        self.bump();
-        // Emit the error ...
+        // Emit the error...
+        let not_token = self.look_ahead(1, |t| t.clone());
         self.struct_span_err(
-            self.token.span,
-            &format!("unexpected {} after identifier", self.this_token_descr()),
+            not_token.span,
+            &format!("unexpected {} after identifier", super::token_descr(&not_token)),
         )
         .span_suggestion_short(
             // Span the `not` plus trailing whitespace to avoid
             // trailing whitespace after the `!` in our suggestion
-            self.sess.source_map().span_until_non_whitespace(lo.to(self.token.span)),
+            self.sess.source_map().span_until_non_whitespace(lo.to(not_token.span)),
             "use `!` to perform logical negation",
             "!".to_owned(),
             Applicability::MachineApplicable,
         )
         .emit();
-        // —and recover! (just as if we were in the block
-        // for the `token::Not` arm)
-        let expr = self.parse_prefix_expr(None);
-        let (span, e) = self.interpolated_or_expr_span(expr)?;
-        Ok((lo.to(span), self.mk_unary(UnOp::Not, e)))
+
+        // ...and recover!
+        self.parse_unary_expr(lo, UnOp::Not)
     }
 
     /// Returns the span of expr, if it was not interpolated or the span of the interpolated token.
@@ -738,7 +720,7 @@ impl<'a> Parser<'a> {
 
     fn error_unexpected_after_dot(&self) {
         // FIXME Could factor this out into non_fatal_unexpected or something.
-        let actual = self.this_token_to_string();
+        let actual = pprust::token_to_string(&self.token);
         self.struct_span_err(self.token.span, &format!("unexpected token: `{}`", actual)).emit();
     }
 
@@ -1142,7 +1124,7 @@ impl<'a> Parser<'a> {
 
     pub(super) fn parse_lit(&mut self) -> PResult<'a, Lit> {
         self.parse_opt_lit().ok_or_else(|| {
-            let msg = format!("unexpected token: {}", self.this_token_descr());
+            let msg = format!("unexpected token: {}", super::token_descr(&self.token));
             self.span_fatal(self.token.span, &msg)
         })
     }
diff --git a/src/librustc_parse/parser/item.rs b/src/librustc_parse/parser/item.rs
index 8f8e5fbb787..343c6667d47 100644
--- a/src/librustc_parse/parser/item.rs
+++ b/src/librustc_parse/parser/item.rs
@@ -1348,7 +1348,7 @@ impl<'a> Parser<'a> {
             self.expect_semi()?;
             body
         } else {
-            let token_str = self.this_token_descr();
+            let token_str = super::token_descr(&self.token);
             let mut err = self.fatal(&format!(
                 "expected `where`, `{{`, `(`, or `;` after struct name, found {}",
                 token_str
@@ -1374,7 +1374,7 @@ impl<'a> Parser<'a> {
             let (fields, recovered) = self.parse_record_struct_body()?;
             VariantData::Struct(fields, recovered)
         } else {
-            let token_str = self.this_token_descr();
+            let token_str = super::token_descr(&self.token);
             let mut err = self
                 .fatal(&format!("expected `where` or `{{` after union name, found {}", token_str));
             err.span_label(self.token.span, "expected `where` or `{` after union name");
@@ -1411,7 +1411,7 @@ impl<'a> Parser<'a> {
             }
             self.eat(&token::CloseDelim(token::Brace));
         } else {
-            let token_str = self.this_token_descr();
+            let token_str = super::token_descr(&self.token);
             let mut err = self.fatal(&format!(
                 "expected `where`, or `{{` after struct name, found {}",
                 token_str
@@ -1498,7 +1498,7 @@ impl<'a> Parser<'a> {
                 let sp = self.sess.source_map().next_point(self.prev_span);
                 let mut err = self.struct_span_err(
                     sp,
-                    &format!("expected `,`, or `}}`, found {}", self.this_token_descr()),
+                    &format!("expected `,`, or `}}`, found {}", super::token_descr(&self.token)),
                 );
                 if self.token.is_ident() {
                     // This is likely another field; emit the diagnostic and keep going
diff --git a/src/librustc_parse/parser/mod.rs b/src/librustc_parse/parser/mod.rs
index 97084482025..103bbe5dd76 100644
--- a/src/librustc_parse/parser/mod.rs
+++ b/src/librustc_parse/parser/mod.rs
@@ -354,6 +354,24 @@ pub enum FollowedByType {
     No,
 }
 
+fn token_descr_opt(token: &Token) -> Option<&'static str> {
+    Some(match token.kind {
+        _ if token.is_special_ident() => "reserved identifier",
+        _ if token.is_used_keyword() => "keyword",
+        _ if token.is_unused_keyword() => "reserved keyword",
+        token::DocComment(..) => "doc comment",
+        _ => return None,
+    })
+}
+
+pub(super) fn token_descr(token: &Token) -> String {
+    let token_str = pprust::token_to_string(token);
+    match token_descr_opt(token) {
+        Some(prefix) => format!("{} `{}`", prefix, token_str),
+        _ => format!("`{}`", token_str),
+    }
+}
+
 impl<'a> Parser<'a> {
     pub fn new(
         sess: &'a ParseSess,
@@ -422,29 +440,6 @@ impl<'a> Parser<'a> {
         next
     }
 
-    /// Converts the current token to a string using `self`'s reader.
-    pub fn this_token_to_string(&self) -> String {
-        pprust::token_to_string(&self.token)
-    }
-
-    fn token_descr(&self) -> Option<&'static str> {
-        Some(match &self.token.kind {
-            _ if self.token.is_special_ident() => "reserved identifier",
-            _ if self.token.is_used_keyword() => "keyword",
-            _ if self.token.is_unused_keyword() => "reserved keyword",
-            token::DocComment(..) => "doc comment",
-            _ => return None,
-        })
-    }
-
-    pub(super) fn this_token_descr(&self) -> String {
-        if let Some(prefix) = self.token_descr() {
-            format!("{} `{}`", prefix, self.this_token_to_string())
-        } else {
-            format!("`{}`", self.this_token_to_string())
-        }
-    }
-
     crate fn unexpected<T>(&mut self) -> PResult<'a, T> {
         match self.expect_one_of(&[], &[]) {
             Err(e) => Err(e),
diff --git a/src/librustc_parse/parser/module.rs b/src/librustc_parse/parser/module.rs
index eaeb3af4ca2..3f54e0b6de0 100644
--- a/src/librustc_parse/parser/module.rs
+++ b/src/librustc_parse/parser/module.rs
@@ -79,7 +79,7 @@ impl<'a> Parser<'a> {
         }
 
         if !self.eat(term) {
-            let token_str = self.this_token_descr();
+            let token_str = super::token_descr(&self.token);
             if !self.maybe_consume_incorrect_semicolon(&items) {
                 let mut err = self.fatal(&format!("expected item, found {}", token_str));
                 err.span_label(self.token.span, "expected item");
diff --git a/src/librustc_parse/parser/pat.rs b/src/librustc_parse/parser/pat.rs
index 9b5bf7e2378..01b122618ac 100644
--- a/src/librustc_parse/parser/pat.rs
+++ b/src/librustc_parse/parser/pat.rs
@@ -670,7 +670,7 @@ impl<'a> Parser<'a> {
         err.cancel();
 
         let expected = expected.unwrap_or("pattern");
-        let msg = format!("expected {}, found {}", expected, self.this_token_descr());
+        let msg = format!("expected {}, found {}", expected, super::token_descr(&self.token));
 
         let mut err = self.fatal(&msg);
         err.span_label(self.token.span, format!("expected {}", expected));
@@ -875,7 +875,7 @@ impl<'a> Parser<'a> {
                     etc_span = Some(etc_sp);
                     break;
                 }
-                let token_str = self.this_token_descr();
+                let token_str = super::token_descr(&self.token);
                 let mut err = self.fatal(&format!("expected `}}`, found {}", token_str));
 
                 err.span_label(self.token.span, "expected `}`");
diff --git a/src/librustc_parse/parser/stmt.rs b/src/librustc_parse/parser/stmt.rs
index 44a197503bd..8270da6c023 100644
--- a/src/librustc_parse/parser/stmt.rs
+++ b/src/librustc_parse/parser/stmt.rs
@@ -323,7 +323,7 @@ impl<'a> Parser<'a> {
 
     fn error_block_no_opening_brace<T>(&mut self) -> PResult<'a, T> {
         let sp = self.token.span;
-        let tok = self.this_token_descr();
+        let tok = super::token_descr(&self.token);
         let mut e = self.span_fatal(sp, &format!("expected `{{`, found {}", tok));
         let do_not_suggest_help = self.token.is_keyword(kw::In) || self.token == token::Colon;
 
@@ -463,7 +463,7 @@ impl<'a> Parser<'a> {
     fn warn_missing_semicolon(&self) {
         self.diagnostic()
             .struct_span_warn(self.token.span, {
-                &format!("expected `;`, found {}", self.this_token_descr())
+                &format!("expected `;`, found {}", super::token_descr(&self.token))
             })
             .note({
                 "this was erroneously allowed and will become a hard error in a future release"
diff --git a/src/librustc_parse/parser/ty.rs b/src/librustc_parse/parser/ty.rs
index fe3db358acc..049c077c3ce 100644
--- a/src/librustc_parse/parser/ty.rs
+++ b/src/librustc_parse/parser/ty.rs
@@ -135,7 +135,7 @@ impl<'a> Parser<'a> {
                 TyKind::Err
             }
         } else {
-            let msg = format!("expected type, found {}", self.this_token_descr());
+            let msg = format!("expected type, found {}", super::token_descr(&self.token));
             let mut err = self.struct_span_err(self.token.span, &msg);
             err.span_label(self.token.span, "expected type");
             self.maybe_annotate_with_ascription(&mut err, true);
diff --git a/src/libsyntax_expand/expand.rs b/src/libsyntax_expand/expand.rs
index b9b449d1779..4df51ff41f3 100644
--- a/src/libsyntax_expand/expand.rs
+++ b/src/libsyntax_expand/expand.rs
@@ -904,10 +904,8 @@ pub fn ensure_complete_parse<'a>(
     span: Span,
 ) {
     if this.token != token::Eof {
-        let msg = format!(
-            "macro expansion ignores token `{}` and any following",
-            this.this_token_to_string()
-        );
+        let token = pprust::token_to_string(&this.token);
+        let msg = format!("macro expansion ignores token `{}` and any following", token);
         // Avoid emitting backtrace info twice.
         let def_site_span = this.token.span.with_ctxt(SyntaxContext::root());
         let mut err = this.struct_span_err(def_site_span, &msg);
diff --git a/src/libsyntax_ext/source_util.rs b/src/libsyntax_ext/source_util.rs
index 4f46252f8be..fccc36e2ea8 100644
--- a/src/libsyntax_ext/source_util.rs
+++ b/src/libsyntax_ext/source_util.rs
@@ -133,15 +133,17 @@ pub fn expand_include<'cx>(
             while self.p.token != token::Eof {
                 match panictry!(self.p.parse_item()) {
                     Some(item) => ret.push(item),
-                    None => self
-                        .p
-                        .sess
-                        .span_diagnostic
-                        .span_fatal(
-                            self.p.token.span,
-                            &format!("expected item, found `{}`", self.p.this_token_to_string()),
-                        )
-                        .raise(),
+                    None => {
+                        let token = pprust::token_to_string(&self.p.token);
+                        self.p
+                            .sess
+                            .span_diagnostic
+                            .span_fatal(
+                                self.p.token.span,
+                                &format!("expected item, found `{}`", token),
+                            )
+                            .raise();
+                    }
                 }
             }
             Some(ret)