Auto merge of #23796 - alexcrichton:rollup, r=alexcrichton

4 files changed, 48 insertions, 96 deletions

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 0843713681b..e11e9f62a5b 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -742,6 +742,7 @@ impl<'a> StringReader<'a> {
         let start_bpos = self.last_pos;
         let mut accum_int = 0;
 
+        let mut valid = true;
         for _ in 0..n_digits {
             if self.is_eof() {
                 let last_bpos = self.last_pos;
@@ -750,6 +751,7 @@ impl<'a> StringReader<'a> {
             if self.curr_is(delim) {
                 let last_bpos = self.last_pos;
                 self.err_span_(start_bpos, last_bpos, "numeric character escape is too short");
+                valid = false;
                 break;
             }
             let c = self.curr.unwrap_or('\x00');
@@ -757,6 +759,8 @@ impl<'a> StringReader<'a> {
             accum_int += c.to_digit(16).unwrap_or_else(|| {
                 self.err_span_char(self.last_pos, self.pos,
                               "illegal character in numeric character escape", c);
+
+                valid = false;
                 0
             });
             self.bump();
@@ -767,10 +771,11 @@ impl<'a> StringReader<'a> {
                            self.last_pos,
                            "this form of character escape may only be used \
                             with characters in the range [\\x00-\\x7f]");
+            valid = false;
         }
 
         match char::from_u32(accum_int) {
-            Some(_) => true,
+            Some(_) => valid,
             None => {
                 let last_bpos = self.last_pos;
                 self.err_span_(start_bpos, last_bpos, "illegal numeric character escape");
@@ -799,7 +804,18 @@ impl<'a> StringReader<'a> {
                             'n' | 'r' | 't' | '\\' | '\'' | '"' | '0' => true,
                             'x' => self.scan_byte_escape(delim, !ascii_only),
                             'u' if self.curr_is('{') => {
-                                self.scan_unicode_escape(delim)
+                            let valid = self.scan_unicode_escape(delim);
+                            if valid && ascii_only {
+                                self.err_span_(
+                                    escaped_pos,
+                                    self.last_pos,
+                                    "unicode escape sequences cannot be used as a byte or in \
+                                    a byte string"
+                                );
+                                false
+                            } else {
+                               valid
+                            }
                             }
                             '\n' if delim == '"' => {
                                 self.consume_whitespace();
@@ -869,6 +885,7 @@ impl<'a> StringReader<'a> {
         let start_bpos = self.last_pos;
         let mut count = 0;
         let mut accum_int = 0;
+        let mut valid = true;
 
         while !self.curr_is('}') && count <= 6 {
             let c = match self.curr {
@@ -884,29 +901,30 @@ impl<'a> StringReader<'a> {
                     self.fatal_span_(self.last_pos, self.pos,
                                      "unterminated unicode escape (needed a `}`)");
                 } else {
-                    self.fatal_span_char(self.last_pos, self.pos,
+                    self.err_span_char(self.last_pos, self.pos,
                                    "illegal character in unicode escape", c);
                 }
+                valid = false;
+                0
             });
             self.bump();
             count += 1;
         }
 
         if count > 6 {
-            self.fatal_span_(start_bpos, self.last_pos,
+            self.err_span_(start_bpos, self.last_pos,
                           "overlong unicode escape (can have at most 6 hex digits)");
+            valid = false;
         }
 
         self.bump(); // past the ending }
 
-        let mut valid = count >= 1 && count <= 6;
-        if char::from_u32(accum_int).is_none() {
-            valid = false;
+        if valid && (char::from_u32(accum_int).is_none() || count == 0) {
+            self.err_span_(start_bpos, self.last_pos, "illegal unicode character escape");
+            valid= false;
         }
 
-        if !valid {
-            self.fatal_span_(start_bpos, self.last_pos, "illegal unicode character escape");
-        }
+
         valid
     }
 
@@ -1330,7 +1348,7 @@ impl<'a> StringReader<'a> {
                 "unterminated byte constant".to_string());
         }
 
-        let id = if valid { self.name_from(start) } else { token::intern("??") };
+        let id = if valid { self.name_from(start) } else { token::intern("?") };
         self.bump(); // advance curr past token
         return token::Byte(id);
     }
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 4e851761212..bea42a88bf5 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -700,18 +700,18 @@ pub fn integer_lit(s: &str, suffix: Option<&str>, sd: &SpanHandler, sp: Span) ->
     if let Some(suf) = suffix {
         if suf.is_empty() { sd.span_bug(sp, "found empty literal suffix in Some")}
         ty = match suf {
-            "isize" => ast::SignedIntLit(ast::TyIs(false), ast::Plus),
+            "isize" => ast::SignedIntLit(ast::TyIs, ast::Plus),
             "i8"  => ast::SignedIntLit(ast::TyI8, ast::Plus),
             "i16" => ast::SignedIntLit(ast::TyI16, ast::Plus),
             "i32" => ast::SignedIntLit(ast::TyI32, ast::Plus),
             "i64" => ast::SignedIntLit(ast::TyI64, ast::Plus),
-            "usize" => ast::UnsignedIntLit(ast::TyUs(false)),
+            "usize" => ast::UnsignedIntLit(ast::TyUs),
             "u8"  => ast::UnsignedIntLit(ast::TyU8),
             "u16" => ast::UnsignedIntLit(ast::TyU16),
             "u32" => ast::UnsignedIntLit(ast::TyU32),
             "u64" => ast::UnsignedIntLit(ast::TyU64),
-            "i" | "is" => ast::SignedIntLit(ast::TyIs(true), ast::Plus),
-            "u" | "us" => ast::UnsignedIntLit(ast::TyUs(true)),
+            "is" => ast::SignedIntLit(ast::TyIs, ast::Plus),
+            "us" => ast::UnsignedIntLit(ast::TyUs),
             _ => {
                 // i<digits> and u<digits> look like widths, so lets
                 // give an error message along those lines
diff --git a/src/libsyntax/parse/obsolete.rs b/src/libsyntax/parse/obsolete.rs
index 276be73823a..bb9b586bb3f 100644
--- a/src/libsyntax/parse/obsolete.rs
+++ b/src/libsyntax/parse/obsolete.rs
@@ -23,7 +23,6 @@ use ptr::P;
 #[derive(Copy, PartialEq, Eq, Hash)]
 pub enum ObsoleteSyntax {
     ClosureKind,
-    EmptyIndex,
     ExternCrateString,
 }
 
@@ -52,11 +51,6 @@ impl<'a> ParserObsoleteMethods for parser::Parser<'a> {
                 "rely on inference instead",
                 true,
             ),
-            ObsoleteSyntax::EmptyIndex => (
-                "[]",
-                "write `[..]` instead",
-                false, // warning for now
-            ),
             ObsoleteSyntax::ExternCrateString => (
                 "\"crate-name\"",
                 "use an identifier not in quotes instead",
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 786970ce252..b287093bf19 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -2312,46 +2312,13 @@ impl<'a> Parser<'a> {
               // expr[...]
               // Could be either an index expression or a slicing expression.
               token::OpenDelim(token::Bracket) => {
-                let bracket_pos = self.span.lo;
                 self.bump();
 
-                if self.eat(&token::CloseDelim(token::Bracket)) {
-                    // No expression, expand to a RangeFull
-                    // FIXME(#20516) It would be better to use a lang item or
-                    // something for RangeFull.
-                    hi = self.last_span.hi;
-
-                    let idents = vec![token::str_to_ident("std"),
-                                      token::str_to_ident("ops"),
-                                      token::str_to_ident("RangeFull")];
-                    let segments = idents.into_iter().map(|ident| {
-                        ast::PathSegment {
-                            identifier: ident,
-                            parameters: ast::PathParameters::none(),
-                        }
-                    }).collect();
-                    let span = mk_sp(lo, hi);
-                    let path = ast::Path {
-                        span: span,
-                        global: true,
-                        segments: segments,
-                    };
-
-                    let range = ExprStruct(path, vec![], None);
-                    let ix = self.mk_expr(bracket_pos, hi, range);
-                    let index = self.mk_index(e, ix);
-                    e = self.mk_expr(lo, hi, index);
-
-                    let obsolete_span = mk_sp(bracket_pos, hi);
-                    self.obsolete(obsolete_span, ObsoleteSyntax::EmptyIndex);
-                } else {
-                    let ix = self.parse_expr();
-                    hi = self.span.hi;
-                    self.commit_expr_expecting(&*ix, token::CloseDelim(token::Bracket));
-                    let index = self.mk_index(e, ix);
-                    e = self.mk_expr(lo, hi, index)
-                }
-
+                let ix = self.parse_expr();
+                hi = self.span.hi;
+                self.commit_expr_expecting(&*ix, token::CloseDelim(token::Bracket));
+                let index = self.mk_index(e, ix);
+                e = self.mk_expr(lo, hi, index)
               }
               _ => return e
             }
@@ -4984,46 +4951,19 @@ impl<'a> Parser<'a> {
     ///
     /// # Examples
     ///
-    /// extern crate url;
-    /// extern crate foo = "bar"; //deprecated
-    /// extern crate "bar" as foo;
+    /// extern crate foo;
+    /// extern crate bar as foo;
     fn parse_item_extern_crate(&mut self,
-                                lo: BytePos,
-                                visibility: Visibility,
-                                attrs: Vec<Attribute>)
+                               lo: BytePos,
+                               visibility: Visibility,
+                               attrs: Vec<Attribute>)
                                 -> P<Item> {
 
-        let (maybe_path, ident) = match self.token {
-            token::Ident(..) => {
-                let crate_name = self.parse_ident();
-                if self.eat_keyword(keywords::As) {
-                    (Some(crate_name.name), self.parse_ident())
-                } else {
-                    (None, crate_name)
-                }
-            },
-            token::Literal(token::Str_(..), suf) |
-            token::Literal(token::StrRaw(..), suf) => {
-                let sp = self.span;
-                self.expect_no_suffix(sp, "extern crate name", suf);
-                // forgo the internal suffix check of `parse_str` to
-                // avoid repeats (this unwrap will always succeed due
-                // to the restriction of the `match`)
-                let (s, _, _) = self.parse_optional_str().unwrap();
-                self.expect_keyword(keywords::As);
-                let the_ident = self.parse_ident();
-                self.obsolete(sp, ObsoleteSyntax::ExternCrateString);
-                let s = token::intern(&s);
-                (Some(s), the_ident)
-            },
-            _ => {
-                let span = self.span;
-                let token_str = self.this_token_to_string();
-                self.span_fatal(span,
-                                &format!("expected extern crate name but \
-                                         found `{}`",
-                                        token_str));
-            }
+        let crate_name = self.parse_ident();
+        let (maybe_path, ident) = if self.eat_keyword(keywords::As) {
+            (Some(crate_name.name), self.parse_ident())
+        } else {
+            (None, crate_name)
         };
         self.expect(&token::Semi);