Auto merge of #54403 - eddyb:oopsie-daisy-stabilize, r=alexcrichton

Stabilize crate_in_paths, extern_absolute_paths and extern_prelude on all editions.

Needed for beta, path-related migrations to Rust 2018 don't work on RC1 without these stabilizations.

r? @aturon cc @nikomatsakis @Centril @alexcrichton

src/librustc/lib.rs

@@ -73,7 +73,7 @@
 #![cfg_attr(not(stage0), feature(impl_header_lifetime_elision))]
 #![feature(in_band_lifetimes)]
 #![feature(macro_at_most_once_rep)]
-#![feature(crate_in_paths)]
+#![cfg_attr(stage0, feature(crate_in_paths))]
 #![feature(crate_visibility_modifier)]
 
 #![recursion_limit="512"]

src/librustc_resolve/lib.rs

@@ -65,7 +65,6 @@ use syntax::ast::{FnDecl, ForeignItem, ForeignItemKind, GenericParamKind, Generi
 use syntax::ast::{Item, ItemKind, ImplItem, ImplItemKind};
 use syntax::ast::{Label, Local, Mutability, Pat, PatKind, Path};
 use syntax::ast::{QSelf, TraitItemKind, TraitRef, Ty, TyKind};
-use syntax::feature_gate::{feature_err, GateIssue};
 use syntax::ptr::P;
 
 use syntax_pos::{Span, DUMMY_SP, MultiSpan};
@@ -1466,9 +1465,6 @@ pub struct Resolver<'a, 'b: 'a> {
     current_type_ascription: Vec<Span>,
 
     injected_crate: Option<Module<'a>>,
-
-    /// Only supposed to be used by rustdoc, otherwise should be false.
-    pub ignore_extern_prelude_feature: bool,
 }
 
 /// Nothing really interesting here, it just provides memory for the rest of the crate.
@@ -1766,7 +1762,6 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
             unused_macros: FxHashSet(),
             current_type_ascription: Vec::new(),
             injected_crate: None,
-            ignore_extern_prelude_feature: false,
         }
     }
 
@@ -1969,13 +1964,6 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
         if !module.no_implicit_prelude {
             // `record_used` means that we don't try to load crates during speculative resolution
             if record_used && ns == TypeNS && self.extern_prelude.contains(&ident.name) {
-                if !self.session.features_untracked().extern_prelude &&
-                   !self.ignore_extern_prelude_feature {
-                    feature_err(&self.session.parse_sess, "extern_prelude",
-                                ident.span, GateIssue::Language,
-                                "access to extern crates through prelude is experimental").emit();
-                }
-
                 let crate_id = self.crate_loader.process_path_extern(ident.name, ident.span);
                 let crate_root = self.get_module(DefId { krate: crate_id, index: CRATE_DEF_INDEX });
                 self.populate_module_if_necessary(&crate_root);
@@ -3576,7 +3564,6 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
                     }
                     if name == keywords::Extern.name() ||
                        name == keywords::CrateRoot.name() &&
-                       self.session.features_untracked().extern_absolute_paths &&
                        self.session.rust_2018() {
                         module = Some(ModuleOrUniformRoot::UniformRoot(name));
                         continue;
@@ -3715,12 +3702,6 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
             return
         }
 
-        // In the 2015 edition there's no use in emitting lints unless the
-        // crate's already enabled the feature that we're going to suggest
-        if !self.session.features_untracked().crate_in_paths {
-            return
-        }
-
         let (diag_id, diag_span) = match crate_lint {
             CrateLint::No => return,
             CrateLint::SimplePath(id) => (id, path_span),
@@ -4417,7 +4398,7 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
             )
         );
 
-        if self.session.features_untracked().extern_prelude {
+        if self.session.rust_2018() {
             let extern_prelude_names = self.extern_prelude.clone();
             for &name in extern_prelude_names.iter() {
                 let ident = Ident::with_empty_ctxt(name);

src/librustc_resolve/macros.rs

@@ -682,14 +682,6 @@ impl<'a, 'cl> Resolver<'a, 'cl> {
                 }
                 WhereToResolve::ExternPrelude => {
                     if use_prelude && self.extern_prelude.contains(&ident.name) {
-                        if !self.session.features_untracked().extern_prelude &&
-                           !self.ignore_extern_prelude_feature {
-                            feature_err(&self.session.parse_sess, "extern_prelude",
-                                        ident.span, GateIssue::Language,
-                                        "access to extern crates through prelude is experimental")
-                                        .emit();
-                        }
-
                         let crate_id =
                             self.crate_loader.process_path_extern(ident.name, ident.span);
                         let crate_root =

src/librustc_traits/lib.rs

@@ -11,9 +11,9 @@
 //! New recursive solver modeled on Chalk's recursive solver. Most of
 //! the guts are broken up into modules; see the comments in those modules.
 
-#![feature(crate_in_paths)]
+#![cfg_attr(stage0, feature(crate_in_paths))]
 #![feature(crate_visibility_modifier)]
-#![feature(extern_prelude)]
+#![cfg_attr(stage0, feature(extern_prelude))]
 #![feature(in_band_lifetimes)]
 #![cfg_attr(not(stage0), feature(nll))]
 

src/librustdoc/core.rs

@@ -455,12 +455,10 @@ pub fn run_core(search_paths: SearchPaths,
                                                         |_| Ok(()));
         let driver::InnerExpansionResult {
             mut hir_forest,
-            mut resolver,
+            resolver,
             ..
         } = abort_on_err(result, &sess);
 
-        resolver.ignore_extern_prelude_feature = true;
-
         // We need to hold on to the complete resolver, so we clone everything
         // for the analysis passes to use. Suboptimal, but necessary in the
         // current architecture.

src/libsyntax/feature_gate.rs

@@ -394,18 +394,12 @@ declare_features! (
     // Allows trait methods with arbitrary self types
     (active, arbitrary_self_types, "1.23.0", Some(44874), None),
 
-    // `crate` in paths
-    (active, crate_in_paths, "1.23.0", Some(45477), Some(Edition::Edition2018)),
-
     // In-band lifetime bindings (e.g. `fn foo(x: &'a u8) -> &'a u8`)
     (active, in_band_lifetimes, "1.23.0", Some(44524), None),
 
     // Generic associated types (RFC 1598)
     (active, generic_associated_types, "1.23.0", Some(44265), None),
 
-    // Resolve absolute paths as paths from other crates
-    (active, extern_absolute_paths, "1.24.0", Some(44660), Some(Edition::Edition2018)),
-
     // `extern` in paths
     (active, extern_in_paths, "1.23.0", Some(44660), None),
 
@@ -455,9 +449,6 @@ declare_features! (
     // #[doc(alias = "...")]
     (active, doc_alias, "1.27.0", Some(50146), None),
 
-    // Access to crate names passed via `--extern` through prelude
-    (active, extern_prelude, "1.27.0", Some(44660), Some(Edition::Edition2018)),
-
     // Scoped lints
     (active, tool_lints, "1.28.0", Some(44690), None),
 
@@ -683,7 +674,12 @@ declare_features! (
     (accepted, panic_handler, "1.30.0", Some(44489), None),
     // Used to preserve symbols (see llvm.used)
     (accepted, used, "1.30.0", Some(40289), None),
-
+    // `crate` in paths
+    (accepted, crate_in_paths, "1.30.0", Some(45477), None),
+    // Resolve absolute paths as paths from other crates
+    (accepted, extern_absolute_paths, "1.30.0", Some(44660), None),
+    // Access to crate names passed via `--extern` through prelude
+    (accepted, extern_prelude, "1.30.0", Some(44660), None),
 );
 
 // If you change this, please modify src/doc/unstable-book as well. You must
@@ -1892,10 +1888,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             // cannot be kept in identifiers, so it's kept in paths instead and we take it from
             // there while keeping location info from the ident span.
             let span = segment.ident.span.with_ctxt(path.span.ctxt());
-            if segment.ident.name == keywords::Crate.name() {
-                gate_feature_post!(&self, crate_in_paths, span,
-                                   "`crate` in paths is experimental");
-            } else if segment.ident.name == keywords::Extern.name() {
+            if segment.ident.name == keywords::Extern.name() {
                 gate_feature_post!(&self, extern_in_paths, span,
                                    "`extern` in paths is experimental");
             }

src/test/run-make-fulldeps/extern-prelude/Makefile

@@ -7,6 +7,5 @@ all:
 	$(RUSTC) basic.rs --extern ep_lib=$(TMPDIR)/libep_lib.rlib
 	$(RUSTC) shadow-mod.rs --extern ep_lib=$(TMPDIR)/libep_lib.rlib
 	$(RUSTC) shadow-prelude.rs --extern Vec=$(TMPDIR)/libep_vec.rlib
-	$(RUSTC) feature-gate.rs --extern ep_lib=$(TMPDIR)/libep_lib.rlib 2>&1 | $(CGREP) "access to extern crates through prelude is experimental"
 	$(RUSTC) relative-only.rs --extern ep_lib=$(TMPDIR)/libep_lib.rlib 2>&1 | $(CGREP) "unresolved import"
 	$(RUSTC) relative-only.rs --extern ep_lib=$(TMPDIR)/libep_lib.rlib 2>&1 | $(CGREP) "failed to resolve"

src/test/ui/hygiene/dollar-crate-modern.stderr

@@ -0,0 +1,8 @@
+warning: the feature `crate_in_paths` has been stable since 1.30.0 and no longer requires an attribute to enable
+  --> $DIR/dollar-crate-modern.rs:16:24
+   |
+LL | #![feature(decl_macro, crate_in_paths)]
+   |                        ^^^^^^^^^^^^^^
+   |
+   = note: #[warn(stable_features)] on by default
+

src/test/ui/macros/macro-path-prelude-pass.stderr

@@ -0,0 +1,8 @@
+warning: the feature `extern_prelude` has been stable since 1.30.0 and no longer requires an attribute to enable
+  --> $DIR/macro-path-prelude-pass.rs:13:12
+   |
+LL | #![feature(extern_prelude)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: #[warn(stable_features)] on by default
+

src/test/ui/run-pass/extern/extern-prelude-core.stderr

@@ -0,0 +1,8 @@
+warning: the feature `extern_prelude` has been stable since 1.30.0 and no longer requires an attribute to enable
+  --> $DIR/extern-prelude-core.rs:12:12
+   |
+LL | #![feature(extern_prelude, lang_items, start, alloc)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: #[warn(stable_features)] on by default
+

src/test/ui/run-pass/extern/extern-prelude-std.stderr

@@ -0,0 +1,8 @@
+warning: the feature `extern_prelude` has been stable since 1.30.0 and no longer requires an attribute to enable
+  --> $DIR/extern-prelude-std.rs:12:12
+   |
+LL | #![feature(extern_prelude)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: #[warn(stable_features)] on by default
+

src/test/ui/run-pass/rfcs/rfc-2126-crate-paths/crate-path-absolute.stderr

@@ -0,0 +1,8 @@
+warning: the feature `crate_in_paths` has been stable since 1.30.0 and no longer requires an attribute to enable
+  --> $DIR/crate-path-absolute.rs:12:12
+   |
+LL | #![feature(crate_in_paths)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: #[warn(stable_features)] on by default
+

src/test/ui/run-pass/rfcs/rfc-2126-crate-paths/crate-path-visibility-ambiguity.stderr

@@ -0,0 +1,8 @@
+warning: the feature `crate_in_paths` has been stable since 1.30.0 and no longer requires an attribute to enable
+  --> $DIR/crate-path-visibility-ambiguity.rs:12:12
+   |
+LL | #![feature(crate_in_paths)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: #[warn(stable_features)] on by default
+