Rollup merge of rust-lang#65776 - nnethercote:rename-LocalInternedStr…

…ing-and-more, r=estebank

Rename `LocalInternedString` and more

This PR renames `LocalInternedString` as `SymbolStr`, removes an unnecessary `impl` from it, improves comments, and cleans up some `SymbolStr` uses.

r? @estebank

src/librustc/dep_graph/dep_node.rs

@@ -525,7 +525,7 @@ impl<'tcx> DepNodeParams<'tcx> for CrateNum {
     }
 
     fn to_debug_str(&self, tcx: TyCtxt<'tcx>) -> String {
-        tcx.crate_name(*self).as_str().to_string()
+        tcx.crate_name(*self).to_string()
     }
 }
 

src/librustc/hir/lowering.rs

@@ -3382,7 +3382,7 @@ pub fn is_range_literal(sess: &Session, expr: &hir::Expr) -> bool {
     // either in std or core, i.e. has either a `::std::ops::Range` or
     // `::core::ops::Range` prefix.
     fn is_range_path(path: &Path) -> bool {
-        let segs: Vec<_> = path.segments.iter().map(|seg| seg.ident.as_str().to_string()).collect();
+        let segs: Vec<_> = path.segments.iter().map(|seg| seg.ident.to_string()).collect();
         let segs: Vec<_> = segs.iter().map(|seg| &**seg).collect();
 
         // "{{root}}" is the equivalent of `::` prefix in `Path`.
@@ -3423,7 +3423,7 @@ pub fn is_range_literal(sess: &Session, expr: &hir::Expr) -> bool {
         ExprKind::Call(ref func, _) => {
             if let ExprKind::Path(QPath::TypeRelative(ref ty, ref segment)) = func.kind {
                 if let TyKind::Path(QPath::Resolved(None, ref path)) = ty.kind {
-                    let new_call = segment.ident.as_str() == "new";
+                    let new_call = segment.ident.name == sym::new;
                     return is_range_path(&path) && is_lit(sess, &expr.span) && new_call;
                 }
             }

src/librustc/hir/print.rs

@@ -564,7 +564,7 @@ impl<'a> State<'a> {
             }
             hir::ItemKind::GlobalAsm(ref ga) => {
                 self.head(visibility_qualified(&item.vis, "global asm"));
-                self.s.word(ga.asm.as_str().to_string());
+                self.s.word(ga.asm.to_string());
                 self.end()
             }
             hir::ItemKind::TyAlias(ref ty, ref generics) => {
@@ -1855,7 +1855,7 @@ impl<'a> State<'a> {
         self.commasep(Inconsistent, &decl.inputs, |s, ty| {
             s.ibox(INDENT_UNIT);
             if let Some(arg_name) = arg_names.get(i) {
-                s.s.word(arg_name.as_str().to_string());
+                s.s.word(arg_name.to_string());
                 s.s.word(":");
                 s.s.space();
             } else if let Some(body_id) = body_id {

src/librustc/ich/impls_syntax.rs

@@ -9,7 +9,7 @@ use std::mem;
 use syntax::ast;
 use syntax::feature_gate;
 use syntax::parse::token;
-use syntax::symbol::LocalInternedString;
+use syntax::symbol::SymbolStr;
 use syntax::tokenstream;
 use syntax_pos::SourceFile;
 
@@ -18,21 +18,21 @@ use crate::hir::def_id::{DefId, CrateNum, CRATE_DEF_INDEX};
 use smallvec::SmallVec;
 use rustc_data_structures::stable_hasher::{HashStable, ToStableHashKey, StableHasher};
 
-impl<'a> HashStable<StableHashingContext<'a>> for LocalInternedString {
+impl<'a> HashStable<StableHashingContext<'a>> for SymbolStr {
     #[inline]
     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
         let str = self as &str;
         str.hash_stable(hcx, hasher)
     }
 }
 
-impl<'a> ToStableHashKey<StableHashingContext<'a>> for LocalInternedString {
-    type KeyType = LocalInternedString;
+impl<'a> ToStableHashKey<StableHashingContext<'a>> for SymbolStr {
+    type KeyType = SymbolStr;
 
     #[inline]
     fn to_stable_hash_key(&self,
                           _: &StableHashingContext<'a>)
-                          -> LocalInternedString {
+                          -> SymbolStr {
         self.clone()
     }
 }
@@ -45,12 +45,12 @@ impl<'a> HashStable<StableHashingContext<'a>> for ast::Name {
 }
 
 impl<'a> ToStableHashKey<StableHashingContext<'a>> for ast::Name {
-    type KeyType = LocalInternedString;
+    type KeyType = SymbolStr;
 
     #[inline]
     fn to_stable_hash_key(&self,
                           _: &StableHashingContext<'a>)
-                          -> LocalInternedString {
+                          -> SymbolStr {
         self.as_str()
     }
 }

src/librustc/mir/mono.rs

@@ -486,7 +486,7 @@ impl CodegenUnitNameBuilder<'tcx> {
         if self.tcx.sess.opts.debugging_opts.human_readable_cgu_names {
             cgu_name
         } else {
-            let cgu_name = &cgu_name.as_str()[..];
+            let cgu_name = &cgu_name.as_str();
             Symbol::intern(&CodegenUnit::mangle_name(cgu_name))
         }
     }

src/librustc/traits/error_reporting.rs

@@ -1130,7 +1130,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                     let restrict_msg = "consider further restricting this bound";
                     let param_name = self_ty.to_string();
                     for param in generics.params.iter().filter(|p| {
-                        &param_name == std::convert::AsRef::<str>::as_ref(&p.name.ident().as_str())
+                        p.name.ident().as_str() == param_name
                     }) {
                         if param_name.starts_with("impl ") {
                             // `impl Trait` in argument:

src/librustc/traits/on_unimplemented.rs

@@ -180,7 +180,7 @@ impl<'tcx> OnUnimplementedDirective {
                     c.ident().map_or(false, |ident| {
                         options.contains(&(
                             ident.name,
-                            c.value_str().map(|s| s.as_str().to_string())
+                            c.value_str().map(|s| s.to_string())
                         ))
                     })
                 }) {

src/librustc/ty/query/on_disk_cache.rs

@@ -264,7 +264,7 @@ impl<'sess> OnDiskCache<'sess> {
             let sorted_cnums = sorted_cnums_including_local_crate(tcx);
             let prev_cnums: Vec<_> = sorted_cnums.iter()
                 .map(|&cnum| {
-                    let crate_name = tcx.original_crate_name(cnum).as_str().to_string();
+                    let crate_name = tcx.original_crate_name(cnum).to_string();
                     let crate_disambiguator = tcx.crate_disambiguator(cnum);
                     (cnum.as_u32(), crate_name, crate_disambiguator)
                 })

src/librustc_codegen_llvm/attributes.rs

@@ -314,7 +314,7 @@ pub fn from_fn_attrs(
             codegen_fn_attrs.target_features
                 .iter()
                 .map(|f| {
-                    let feature = &*f.as_str();
+                    let feature = &f.as_str();
                     format!("+{}", llvm_util::to_llvm_feature(cx.tcx.sess, feature))
                 })
         )

src/librustc_codegen_llvm/debuginfo/namespace.rs

@@ -34,11 +34,11 @@ pub fn item_namespace(cx: &CodegenCx<'ll, '_>, def_id: DefId) -> &'ll DIScope {
     });
 
     let namespace_name = match def_key.disambiguated_data.data {
-        DefPathData::CrateRoot => cx.tcx.crate_name(def_id.krate).as_str(),
-        data => data.as_symbol().as_str()
+        DefPathData::CrateRoot => cx.tcx.crate_name(def_id.krate),
+        data => data.as_symbol()
     };
 
-    let namespace_name = SmallCStr::new(&namespace_name);
+    let namespace_name = SmallCStr::new(&namespace_name.as_str());
 
     let scope = unsafe {
         llvm::LLVMRustDIBuilderCreateNameSpace(

src/librustc_codegen_ssa/back/command.rs

@@ -53,7 +53,7 @@ impl Command {
     }
 
     pub fn sym_arg(&mut self, arg: Symbol) -> &mut Command {
-        self.arg(&arg.as_str());
+        self.arg(&*arg.as_str());
         self
     }
 

src/librustc_codegen_ssa/back/symbol_export.rs

@@ -129,9 +129,9 @@ fn reachable_non_generics_provider(
                 //
                 // In general though we won't link right if these
                 // symbols are stripped, and LTO currently strips them.
-                if &*name == "rust_eh_personality" ||
-                   &*name == "rust_eh_register_frames" ||
-                   &*name == "rust_eh_unregister_frames" {
+                if name == "rust_eh_personality" ||
+                   name == "rust_eh_register_frames" ||
+                   name == "rust_eh_unregister_frames" {
                     SymbolExportLevel::C
                 } else {
                     SymbolExportLevel::Rust

src/librustc_codegen_ssa/base.rs

@@ -552,8 +552,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
     } else if let Some(kind) = *tcx.sess.allocator_kind.get() {
         let llmod_id = cgu_name_builder.build_cgu_name(LOCAL_CRATE,
                                                        &["crate"],
-                                                       Some("allocator")).as_str()
-                                                                         .to_string();
+                                                       Some("allocator")).to_string();
         let mut modules = backend.new_metadata(tcx, &llmod_id);
         time(tcx.sess, "write allocator module", || {
             backend.codegen_allocator(tcx, &mut modules, kind)
@@ -576,8 +575,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
         // Codegen the encoded metadata.
         let metadata_cgu_name = cgu_name_builder.build_cgu_name(LOCAL_CRATE,
                                                                 &["crate"],
-                                                                Some("metadata")).as_str()
-                                                                                 .to_string();
+                                                                Some("metadata")).to_string();
         let mut metadata_llvm_module = backend.new_metadata(tcx, &metadata_cgu_name);
         time(tcx.sess, "write compressed metadata", || {
             backend.write_compressed_metadata(tcx, &ongoing_codegen.metadata,

src/librustc_codegen_utils/symbol_names/legacy.rs

@@ -121,9 +121,10 @@ fn get_symbol_hash<'tcx>(
         substs.hash_stable(&mut hcx, &mut hasher);
 
         if let Some(instantiating_crate) = instantiating_crate {
-            (&tcx.original_crate_name(instantiating_crate).as_str()[..])
+            tcx.original_crate_name(instantiating_crate).as_str()
+                .hash_stable(&mut hcx, &mut hasher);
+            tcx.crate_disambiguator(instantiating_crate)
                 .hash_stable(&mut hcx, &mut hasher);
-            (&tcx.crate_disambiguator(instantiating_crate)).hash_stable(&mut hcx, &mut hasher);
         }
 
         // We want to avoid accidental collision between different types of instances.

src/librustc_incremental/assert_module_sources.rs

@@ -31,10 +31,6 @@ use syntax::symbol::{Symbol, sym};
 use rustc::ich::{ATTR_PARTITION_REUSED, ATTR_PARTITION_CODEGENED,
                  ATTR_EXPECTED_CGU_REUSE};
 
-const MODULE: Symbol = sym::module;
-const CFG: Symbol = sym::cfg;
-const KIND: Symbol = sym::kind;
-
 pub fn assert_module_sources(tcx: TyCtxt<'_>) {
     tcx.dep_graph.with_ignore(|| {
         if tcx.sess.opts.incremental.is_none() {
@@ -71,7 +67,7 @@ impl AssertModuleSource<'tcx> {
         } else if attr.check_name(ATTR_PARTITION_CODEGENED) {
             (CguReuse::No, ComparisonKind::Exact)
         } else if attr.check_name(ATTR_EXPECTED_CGU_REUSE) {
-            match &self.field(attr, KIND).as_str()[..] {
+            match &*self.field(attr, sym::kind).as_str() {
                 "no" => (CguReuse::No, ComparisonKind::Exact),
                 "pre-lto" => (CguReuse::PreLto, ComparisonKind::Exact),
                 "post-lto" => (CguReuse::PostLto, ComparisonKind::Exact),
@@ -98,8 +94,8 @@ impl AssertModuleSource<'tcx> {
             return;
         }
 
-        let user_path = self.field(attr, MODULE).as_str().to_string();
-        let crate_name = self.tcx.crate_name(LOCAL_CRATE).as_str().to_string();
+        let user_path = self.field(attr, sym::module).to_string();
+        let crate_name = self.tcx.crate_name(LOCAL_CRATE).to_string();
 
         if !user_path.starts_with(&crate_name) {
             let msg = format!("Found malformed codegen unit name `{}`. \
@@ -125,7 +121,7 @@ impl AssertModuleSource<'tcx> {
                                                        cgu_path_components,
                                                        cgu_special_suffix);
 
-        debug!("mapping '{}' to cgu name '{}'", self.field(attr, MODULE), cgu_name);
+        debug!("mapping '{}' to cgu name '{}'", self.field(attr, sym::module), cgu_name);
 
         if !self.available_cgus.contains(&cgu_name) {
             self.tcx.sess.span_err(attr.span,
@@ -135,7 +131,7 @@ impl AssertModuleSource<'tcx> {
                     cgu_name,
                     self.available_cgus
                         .iter()
-                        .map(|cgu| cgu.as_str().to_string())
+                        .map(|cgu| cgu.to_string())
                         .collect::<Vec<_>>()
                         .join(", ")));
         }
@@ -169,7 +165,7 @@ impl AssertModuleSource<'tcx> {
     /// cfg flag called `foo`.
     fn check_config(&self, attr: &ast::Attribute) -> bool {
         let config = &self.tcx.sess.parse_sess.config;
-        let value = self.field(attr, CFG);
+        let value = self.field(attr, sym::cfg);
         debug!("check_config(config={:?}, value={:?})", config, value);
         if config.iter().any(|&(name, _)| name == value) {
             debug!("check_config: matched");

src/librustc_incremental/persist/dirty_clean.rs

@@ -303,7 +303,7 @@ impl DirtyCleanVisitor<'tcx> {
         for item in attr.meta_item_list().unwrap_or_else(Vec::new) {
             if item.check_name(LABEL) {
                 let value = expect_associated_value(self.tcx, &item);
-                return Some(self.resolve_labels(&item, value.as_str().as_ref()));
+                return Some(self.resolve_labels(&item, &value.as_str()));
             }
         }
         None
@@ -314,7 +314,7 @@ impl DirtyCleanVisitor<'tcx> {
         for item in attr.meta_item_list().unwrap_or_else(Vec::new) {
             if item.check_name(EXCEPT) {
                 let value = expect_associated_value(self.tcx, &item);
-                return self.resolve_labels(&item, value.as_str().as_ref());
+                return self.resolve_labels(&item, &value.as_str());
             }
         }
         // if no `label` or `except` is given, only the node's group are asserted

src/librustc_lint/builtin.rs

@@ -1476,14 +1476,12 @@ impl KeywordIdents {
         let mut lint = cx.struct_span_lint(
             KEYWORD_IDENTS,
             ident.span,
-            &format!("`{}` is a keyword in the {} edition",
-                     ident.as_str(),
-                     next_edition),
+            &format!("`{}` is a keyword in the {} edition", ident, next_edition),
         );
         lint.span_suggestion(
             ident.span,
             "you can use a raw identifier to stay compatible",
-            format!("r#{}", ident.as_str()),
+            format!("r#{}", ident),
             Applicability::MachineApplicable,
         );
         lint.emit()

src/librustc_metadata/creader.rs

@@ -121,7 +121,7 @@ impl<'a> CrateLoader<'a> {
             // `source` stores paths which are normalized which may be different
             // from the strings on the command line.
             let source = &self.cstore.get_crate_data(cnum).source;
-            if let Some(entry) = self.sess.opts.externs.get(&*name.as_str()) {
+            if let Some(entry) = self.sess.opts.externs.get(&name.as_str()) {
                 // Only use `--extern crate_name=path` here, not `--extern crate_name`.
                 let found = entry.locations.iter().filter_map(|l| l.as_ref()).any(|l| {
                     let l = fs::canonicalize(l).ok();

src/librustc_metadata/native_libs.rs

@@ -68,7 +68,7 @@ impl ItemLikeVisitor<'tcx> for Collector<'tcx> {
                         Some(name) => name,
                         None => continue, // skip like historical compilers
                     };
-                    lib.kind = match &kind.as_str()[..] {
+                    lib.kind = match &*kind.as_str() {
                         "static" => cstore::NativeStatic,
                         "static-nobundle" => cstore::NativeStaticNobundle,
                         "dylib" => cstore::NativeUnknown,

src/librustc_mir/borrow_check/conflict_errors.rs

@@ -974,7 +974,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let mut err = self.cannot_borrow_across_destructor(borrow_span);
 
         let what_was_dropped = match self.describe_place(place.as_ref()) {
-            Some(name) => format!("`{}`", name.as_str()),
+            Some(name) => format!("`{}`", name),
             None => String::from("temporary value"),
         };
 

src/librustc_mir/interpret/intrinsics.rs

@@ -95,7 +95,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     ) -> InterpResult<'tcx, bool> {
         let substs = instance.substs;
 
-        let intrinsic_name = &self.tcx.item_name(instance.def_id()).as_str()[..];
+        let intrinsic_name = &*self.tcx.item_name(instance.def_id()).as_str();
         match intrinsic_name {
             "caller_location" => {
                 let caller = self.tcx.sess.source_map().lookup_char_pos(span.lo());

src/librustc_mir/transform/check_unsafety.rs

@@ -642,17 +642,17 @@ pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: DefId) {
                 struct_span_err!(
                     tcx.sess, source_info.span, E0133,
                     "{} is unsafe and requires unsafe function or block", description)
-                    .span_label(source_info.span, &description.as_str()[..])
-                    .note(&details.as_str()[..])
+                    .span_label(source_info.span, &*description.as_str())
+                    .note(&details.as_str())
                     .emit();
             }
             UnsafetyViolationKind::ExternStatic(lint_hir_id) => {
                 tcx.lint_node_note(SAFE_EXTERN_STATICS,
                               lint_hir_id,
                               source_info.span,
                               &format!("{} is unsafe and requires unsafe function or block \
-                                        (error E0133)", &description.as_str()[..]),
-                              &details.as_str()[..]);
+                                        (error E0133)", description),
+                              &details.as_str());
             }
             UnsafetyViolationKind::BorrowPacked(lint_hir_id) => {
                 if let Some(impl_def_id) = builtin_derive_def_id(tcx, def_id) {
@@ -662,8 +662,8 @@ pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: DefId) {
                                   lint_hir_id,
                                   source_info.span,
                                   &format!("{} is unsafe and requires unsafe function or block \
-                                            (error E0133)", &description.as_str()[..]),
-                                  &details.as_str()[..]);
+                                            (error E0133)", description),
+                                  &details.as_str());
                 }
             }
         }

src/librustc_mir/transform/qualify_consts.rs

@@ -537,7 +537,7 @@ impl Qualif for IsNotPromotable {
                     Abi::RustIntrinsic |
                     Abi::PlatformIntrinsic => {
                         assert!(!cx.tcx.is_const_fn(def_id));
-                        match &cx.tcx.item_name(def_id).as_str()[..] {
+                        match &*cx.tcx.item_name(def_id).as_str() {
                             | "size_of"
                             | "min_align_of"
                             | "needs_drop"
@@ -1477,7 +1477,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
                         Abi::RustIntrinsic |
                         Abi::PlatformIntrinsic => {
                             assert!(!self.tcx.is_const_fn(def_id));
-                            match &self.tcx.item_name(def_id).as_str()[..] {
+                            match &*self.tcx.item_name(def_id).as_str() {
                                 // special intrinsic that can be called diretly without an intrinsic
                                 // feature gate needs a language feature gate
                                 "transmute" => {

src/librustc_mir/transform/qualify_min_const_fn.rs

@@ -402,7 +402,7 @@ fn check_terminator(
 ///
 /// Adding more intrinsics requires sign-off from @rust-lang/lang.
 fn is_intrinsic_whitelisted(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
-    match &tcx.item_name(def_id).as_str()[..] {
+    match &*tcx.item_name(def_id).as_str() {
         | "size_of"
         | "min_align_of"
         | "needs_drop"