Auto merge of #46972 - Zoxc:internedstring-no-deref, r=<try>

Store a Symbol in InternedString

src/libproc_macro/lib.rs

@@ -407,8 +407,8 @@ impl Term {
 
     /// Get a reference to the interned string.
     #[unstable(feature = "proc_macro", issue = "38356")]
-    pub fn as_str(&self) -> &str {
-        unsafe { &*(&*self.0.as_str() as *const str) }
+    pub fn with_str<F: FnOnce(&str) -> R, R>(self, f: F) -> R {
+        self.0.with_str(f)
     }
 }
 
@@ -678,8 +678,11 @@ impl TokenTree {
             },
             TokenNode::Term(symbol) => {
                 let ident = ast::Ident { name: symbol.0, ctxt: self.span.0.ctxt() };
-                let token =
-                    if symbol.0.as_str().starts_with("'") { Lifetime(ident) } else { Ident(ident) };
+                let token = if symbol.0.with_str(|str| str.starts_with("'")) {
+                    Lifetime(ident)
+                } else {
+                    Ident(ident)
+                };
                 return TokenTree::Token(self.span.0, token).into();
             }
             TokenNode::Literal(token) => return TokenTree::Token(self.span.0, token.0).into(),

src/libproc_macro/quote.rs

@@ -162,7 +162,7 @@ impl Quote for usize {
 
 impl Quote for Term {
     fn quote(self) -> TokenStream {
-        quote!(::Term::intern((quote self.as_str())))
+        self.with_str(|str| quote!(::Term::intern((quote str))))
     }
 }
 

src/librustc/hir/check_attr.rs

@@ -49,11 +49,11 @@ impl<'a> CheckAttrVisitor<'a> {
     /// Check any attribute.
     fn check_attribute(&self, attr: &ast::Attribute, item: &ast::Item, target: Target) {
         if let Some(name) = attr.name() {
-            match &*name.as_str() {
+            name.with_str(|str| match str {
                 "inline" => self.check_inline(attr, item, target),
                 "repr" => self.check_repr(attr, item, target),
                 _ => (),
-            }
+            })
         }
     }
 
@@ -86,7 +86,7 @@ impl<'a> CheckAttrVisitor<'a> {
                 None => continue,
             };
 
-            let (message, label) = match &*name.as_str() {
+            let (message, label) = match &*name.to_string() {
                 "C" => {
                     is_c = true;
                     if target != Target::Struct &&

src/librustc/hir/mod.rs

@@ -1844,7 +1844,7 @@ pub struct StructField {
 impl StructField {
     // Still necessary in couple of places
     pub fn is_positional(&self) -> bool {
-        let first = self.name.as_str().as_bytes()[0];
+        let first = self.name.with_str(|str| str.as_bytes()[0]);
         first >= b'0' && first <= b'9'
     }
 }

src/librustc/hir/print.rs

@@ -528,11 +528,13 @@ impl<'a> State<'a> {
                 self.head(&visibility_qualified(&item.vis, "extern crate"))?;
                 if let Some(p) = *optional_path {
                     let val = p.as_str();
-                    if val.contains("-") {
-                        self.print_string(&val, ast::StrStyle::Cooked)?;
-                    } else {
-                        self.print_name(p)?;
-                    }
+                    val.with(|str| {
+                        if str.contains("-") {
+                            self.print_string(str, ast::StrStyle::Cooked)
+                        } else {
+                            self.print_name(p)
+                        }
+                    })?;
                     self.s.space()?;
                     self.s.word("as")?;
                     self.s.space()?;
@@ -623,7 +625,7 @@ impl<'a> State<'a> {
             }
             hir::ItemGlobalAsm(ref ga) => {
                 self.head(&visibility_qualified(&item.vis, "global asm"))?;
-                self.s.word(&ga.asm.as_str())?;
+                ga.asm.with_str(|str| self.s.word(str))?;
                 self.end()?
             }
             hir::ItemTy(ref ty, ref generics) => {
@@ -1469,20 +1471,21 @@ impl<'a> State<'a> {
             hir::ExprInlineAsm(ref a, ref outputs, ref inputs) => {
                 self.s.word("asm!")?;
                 self.popen()?;
-                self.print_string(&a.asm.as_str(), a.asm_str_style)?;
+                a.asm.with_str(|str| self.print_string(str, a.asm_str_style))?;
                 self.word_space(":")?;
 
                 let mut out_idx = 0;
                 self.commasep(Inconsistent, &a.outputs, |s, out| {
-                    let constraint = out.constraint.as_str();
-                    let mut ch = constraint.chars();
-                    match ch.next() {
-                        Some('=') if out.is_rw => {
-                            s.print_string(&format!("+{}", ch.as_str()),
-                                           ast::StrStyle::Cooked)?
+                    out.constraint.with_str(|constraint| {
+                        let mut ch = constraint.chars();
+                        match ch.next() {
+                            Some('=') if out.is_rw => {
+                                s.print_string(&format!("+{}", ch.as_str()),
+                                            ast::StrStyle::Cooked)
+                            }
+                            _ => s.print_string(&constraint, ast::StrStyle::Cooked)
                         }
-                        _ => s.print_string(&constraint, ast::StrStyle::Cooked)?,
-                    }
+                    })?;
                     s.popen()?;
                     s.print_expr(&outputs[out_idx])?;
                     s.pclose()?;
@@ -1494,7 +1497,7 @@ impl<'a> State<'a> {
 
                 let mut in_idx = 0;
                 self.commasep(Inconsistent, &a.inputs, |s, co| {
-                    s.print_string(&co.as_str(), ast::StrStyle::Cooked)?;
+                    co.with_str(|str| s.print_string(str, ast::StrStyle::Cooked))?;
                     s.popen()?;
                     s.print_expr(&inputs[in_idx])?;
                     s.pclose()?;
@@ -1505,7 +1508,7 @@ impl<'a> State<'a> {
                 self.word_space(":")?;
 
                 self.commasep(Inconsistent, &a.clobbers, |s, co| {
-                    s.print_string(&co.as_str(), ast::StrStyle::Cooked)?;
+                    co.with_str(|str| s.print_string(str, ast::StrStyle::Cooked))?;
                     Ok(())
                 })?;
 
@@ -1578,7 +1581,7 @@ impl<'a> State<'a> {
     }
 
     pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
-        self.s.word(&name.as_str())?;
+        name.with_str(|str| self.s.word(str))?;
         self.ann.post(self, NodeName(&name))
     }
 
@@ -1936,7 +1939,7 @@ impl<'a> State<'a> {
         self.commasep(Inconsistent, &decl.inputs, |s, ty| {
             s.ibox(indent_unit)?;
             if let Some(name) = arg_names.get(i) {
-                s.s.word(&name.node.as_str())?;
+                name.node.with_str(|str| s.s.word(str))?;
                 s.s.word(":")?;
                 s.s.space()?;
             } else if let Some(body_id) = body_id {

src/librustc/ich/impls_syntax.rs

@@ -33,8 +33,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for InternedString {
     fn hash_stable<W: StableHasherResult>(&self,
                                           hcx: &mut StableHashingContext<'gcx>,
                                           hasher: &mut StableHasher<W>) {
-        let s: &str = &**self;
-        s.hash_stable(hcx, hasher);
+        self.with(|str| str.hash_stable(hcx, hasher));
     }
 }
 

src/librustc/lint/levels.rs

@@ -197,7 +197,8 @@ impl<'a> LintLevelsBuilder<'a> {
                       "malformed lint attribute");
         };
         for attr in attrs {
-            let level = match attr.name().and_then(|name| Level::from_str(&name.as_str())) {
+            let level = match attr.name()
+                                  .and_then(|name| name.with_str(|str| Level::from_str(str))) {
                 None => continue,
                 Some(lvl) => lvl,
             };
@@ -221,7 +222,7 @@ impl<'a> LintLevelsBuilder<'a> {
                     }
                 };
                 let name = word.name();
-                match store.check_lint_name(&name.as_str()) {
+                match name.with_str(|str| store.check_lint_name(str)) {
                     CheckLintNameResult::Ok(ids) => {
                         let src = LintSource::Node(name, li.span);
                         for id in ids {
@@ -256,8 +257,8 @@ impl<'a> LintLevelsBuilder<'a> {
                                                 src,
                                                 Some(li.span.into()),
                                                 &msg);
-                        if name.as_str().chars().any(|c| c.is_uppercase()) {
-                            let name_lower = name.as_str().to_lowercase();
+                        if name.with_str(|str| str.chars().any(|c| c.is_uppercase())) {
+                            let name_lower = name.with_str(|str| str.to_lowercase());
                             if let CheckLintNameResult::NoLint =
                                     store.check_lint_name(&name_lower) {
                                 db.emit();

src/librustc/lint/mod.rs

@@ -441,7 +441,7 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
                     &format!("requested on the command line with `{} {}`",
                              flag, hyphen_case_lint_name));
             } else {
-                let hyphen_case_flag_val = lint_flag_val.as_str().replace("_", "-");
+                let hyphen_case_flag_val = lint_flag_val.with_str(|str| str.replace("_", "-"));
                 sess.diag_note_once(
                     &mut err,
                     DiagnosticMessageId::from(lint),

src/librustc/middle/dead.rs

@@ -533,7 +533,7 @@ impl<'a, 'tcx> DeadVisitor<'a, 'tcx> {
                       name: ast::Name,
                       node_type: &str,
                       participle: &str) {
-        if !name.as_str().starts_with("_") {
+        if !name.with_str(|str| str.starts_with("_")) {
             self.tcx
                 .lint_node(lint::builtin::DEAD_CODE,
                            id,

src/librustc/middle/lang_items.rs

@@ -105,7 +105,7 @@ struct LanguageItemCollector<'a, 'tcx: 'a> {
 impl<'a, 'v, 'tcx> ItemLikeVisitor<'v> for LanguageItemCollector<'a, 'tcx> {
     fn visit_item(&mut self, item: &hir::Item) {
         if let Some(value) = extract(&item.attrs) {
-            let item_index = self.item_refs.get(&*value.as_str()).cloned();
+            let item_index = value.with_str(|str| self.item_refs.get(str).cloned());
 
             if let Some(item_index) = item_index {
                 let def_id = self.tcx.hir.local_def_id(item.id);

src/librustc/middle/recursion_limit.rs

@@ -35,7 +35,7 @@ fn update_limit(sess: &Session, krate: &ast::Crate, limit: &Cell<usize>,
         }
 
         if let Some(s) = attr.value_str() {
-            if let Some(n) = s.as_str().parse().ok() {
+            if let Some(n) = s.with_str(|str| str.parse()).ok() {
                 limit.set(n);
                 return;
             }

src/librustc/middle/stability.rs

@@ -164,26 +164,29 @@ impl<'a, 'tcx: 'a> Annotator<'a, 'tcx> {
                 if let (&Some(attr::RustcDeprecation {since: dep_since, ..}),
                         &attr::Stable {since: stab_since}) = (&stab.rustc_depr, &stab.level) {
                     // Explicit version of iter::order::lt to handle parse errors properly
-                    for (dep_v, stab_v) in
-                            dep_since.as_str().split(".").zip(stab_since.as_str().split(".")) {
-                        if let (Ok(dep_v), Ok(stab_v)) = (dep_v.parse::<u64>(), stab_v.parse()) {
-                            match dep_v.cmp(&stab_v) {
-                                Ordering::Less => {
-                                    self.tcx.sess.span_err(item_sp, "An API can't be stabilized \
-                                                                     after it is deprecated");
-                                    break
+                    dep_since.with_str(|dep_since| stab_since.with_str(|stab_since| {
+                        for (dep_v, stab_v) in dep_since.split(".").zip(stab_since.split(".")) {
+                            if let (Ok(dep_v), Ok(stab_v)) = (dep_v.parse::<u64>(),
+                                                              stab_v.parse()) {
+                                match dep_v.cmp(&stab_v) {
+                                    Ordering::Less => {
+                                        self.tcx.sess.span_err(item_sp,
+                                                               "An API can't be stabilized \
+                                                                after it is deprecated");
+                                        break
+                                    }
+                                    Ordering::Equal => continue,
+                                    Ordering::Greater => break,
                                 }
-                                Ordering::Equal => continue,
-                                Ordering::Greater => break,
+                            } else {
+                                // Act like it isn't less because the question is now nonsensical,
+                                // and this makes us not do anything else interesting.
+                                self.tcx.sess.span_err(item_sp, "Invalid stability or deprecation \
+                                                                version found");
+                                break
                             }
-                        } else {
-                            // Act like it isn't less because the question is now nonsensical,
-                            // and this makes us not do anything else interesting.
-                            self.tcx.sess.span_err(item_sp, "Invalid stability or deprecation \
-                                                             version found");
-                            break
                         }
-                    }
+                    }))
                 }
 
                 let hir_id = self.tcx.hir.node_to_hir_id(id);
@@ -620,8 +623,13 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
                 let error_id = (DiagnosticMessageId::StabilityId(issue), span_key, msg.clone());
                 let fresh = self.sess.one_time_diagnostics.borrow_mut().insert(error_id);
                 if fresh {
-                    emit_feature_err(&self.sess.parse_sess, &feature.as_str(), span,
-                                     GateIssue::Library(Some(issue)), &msg);
+                    feature.with_str(|str| {
+                        emit_feature_err(&self.sess.parse_sess,
+                                         str,
+                                         span,
+                                         GateIssue::Library(Some(issue)),
+                                         &msg)
+                    });
                 }
             }
             Some(_) => {
@@ -742,7 +750,7 @@ pub fn check_unused_or_stable_features<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
     remaining_lib_features.remove(&Symbol::intern("proc_macro"));
 
     for &(ref stable_lang_feature, span) in &sess.features.borrow().declared_stable_lang_features {
-        let version = find_lang_feature_accepted_version(&stable_lang_feature.as_str())
+        let version = stable_lang_feature.with_str(|str| find_lang_feature_accepted_version(str))
             .expect("unexpectedly couldn't find version feature was stabilized");
         tcx.lint_node(lint::builtin::STABLE_FEATURES,
                       ast::CRATE_NODE_ID,

src/librustc/middle/weak_lang_items.rs

@@ -130,7 +130,7 @@ impl<'a, 'tcx, 'v> Visitor<'v> for Context<'a, 'tcx> {
 
     fn visit_foreign_item(&mut self, i: &hir::ForeignItem) {
         if let Some(lang_item) = lang_items::extract(&i.attrs) {
-            self.register(&lang_item.as_str(), i.span);
+            lang_item.with_str(|str| self.register(str, i.span));
         }
         intravisit::walk_foreign_item(self, i)
     }

src/librustc/mir/mod.rs

@@ -1652,7 +1652,7 @@ impl<'tcx> Debug for Rvalue<'tcx> {
                             CtorKind::Fictive => {
                                 let mut struct_fmt = fmt.debug_struct("");
                                 for (field, place) in variant_def.fields.iter().zip(places) {
-                                    struct_fmt.field(&field.name.as_str(), place);
+                                    field.name.with_str(|str| struct_fmt.field(str, place));
                                 }
                                 struct_fmt.finish()
                             }
@@ -1671,7 +1671,7 @@ impl<'tcx> Debug for Rvalue<'tcx> {
                             tcx.with_freevars(node_id, |freevars| {
                                 for (freevar, place) in freevars.iter().zip(places) {
                                     let var_name = tcx.hir.name(freevar.var_id());
-                                    struct_fmt.field(&var_name.as_str(), place);
+                                    var_name.with_str(|str| struct_fmt.field(str, place));
                                 }
                             });
 
@@ -1689,7 +1689,7 @@ impl<'tcx> Debug for Rvalue<'tcx> {
                             tcx.with_freevars(node_id, |freevars| {
                                 for (freevar, place) in freevars.iter().zip(places) {
                                     let var_name = tcx.hir.name(freevar.var_id());
-                                    struct_fmt.field(&var_name.as_str(), place);
+                                    var_name.with_str(|str| struct_fmt.field(str, place));
                                 }
                                 struct_fmt.field("$state", &places[freevars.len()]);
                                 for i in (freevars.len() + 1)..places.len() {

src/librustc/traits/error_reporting.rs

@@ -357,14 +357,14 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
             //
             // Currently I'm leaving it for what I need for `try`.
             if self.tcx.trait_of_item(item) == Some(trait_ref.def_id) {
-                method = self.tcx.item_name(item);
+                method = self.tcx.item_name(item).to_string();
                 flags.push(("from_method", None));
                 flags.push(("from_method", Some(&*method)));
             }
         }
 
         if let Some(k) = obligation.cause.span.compiler_desugaring_kind() {
-            desugaring = k.as_symbol().as_str();
+            desugaring = k.as_symbol().to_string();
             flags.push(("from_desugaring", None));
             flags.push(("from_desugaring", Some(&*desugaring)));
         }