Auto merge of #56303 - petrochenkov:stabuseas, r=cramertj

Stabilize `underscore_imports` Closes #48216

Author: bors

src/librustc_mir/lib.rs

@@ -37,7 +37,7 @@ Rust MIR: a lowered representation of Rust. Also: an experiment!
 #![feature(if_while_or_patterns)]
 #![feature(try_from)]
 #![feature(reverse_bits)]
-#![feature(underscore_imports)]
+#![cfg_attr(stage0, feature(underscore_imports))]
 
 #![recursion_limit="256"]
 

src/libsyntax/feature_gate.rs

@@ -400,9 +400,6 @@ declare_features! (
  // Allows `#[repr(packed)]` attribute on structs.
  (active, repr_packed, "1.26.0", Some(33158), None),
 
- // Allows `use path as _;` and `extern crate c as _;`.
- (active, underscore_imports, "1.26.0", Some(48216), None),
-
  // Allows macro invocations in `extern {}` blocks.
  (active, macros_in_extern, "1.27.0", Some(49476), None),
 
@@ -694,6 +691,8 @@ declare_features! (
  (accepted, self_struct_ctor, "1.32.0", Some(51994), None),
  // `Self` in type definitions (RFC 2300)
  (accepted, self_in_typedefs, "1.32.0", Some(49303), None),
+ // `use path as _;` and `extern crate c as _;`
+ (accepted, underscore_imports, "1.33.0", Some(48216), None),
 );
 
 // If you change this, please modify `src/doc/unstable-book` as well. You must
@@ -1547,26 +1546,8 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
  }
  }
 
- fn visit_use_tree(&mut self, use_tree: &'a ast::UseTree, id: NodeId, _nested: bool) {
- if let ast::UseTreeKind::Simple(Some(ident), ..) = use_tree.kind {
- if ident.name == "_" {
- gate_feature_post!(&self, underscore_imports, use_tree.span,
- "renaming imports with `_` is unstable");
- }
- }
-
- visit::walk_use_tree(self, use_tree, id);
- }
-
  fn visit_item(&mut self, i: &'a ast::Item) {
  match i.node {
- ast::ItemKind::ExternCrate(_) => {
- if i.ident.name == "_" {
- gate_feature_post!(&self, underscore_imports, i.span,
- "renaming extern crates with `_` is unstable");
- }
- }
-
  ast::ItemKind::Static(..) |
  ast::ItemKind::Const(_,_) => {
  if i.ident.name == "_" {

src/test/ui/feature-gates/feature-gate-underscore-imports.rs

@@ -1,5 +1,3 @@
-#![feature(underscore_imports)]
-
 #[macro_export]
 macro_rules! do_nothing {
  () => ()

src/test/ui/feature-gates/feature-gate-underscore-imports.stderr

@@ -11,7 +11,6 @@
 // compile-pass
 // aux-build:underscore-imports.rs
 
-#![feature(underscore_imports)]
 #![warn(unused_imports, unused_extern_crates)]
 
 #[macro_use]

src/test/ui/rfc-2166-underscore-imports/auxiliary/underscore-imports.rs

@@ -1,17 +1,17 @@
 warning: unused import: `m::Tr1 as _`
- --> $DIR/basic.rs:37:9
+ --> $DIR/basic.rs:36:9
  |
 LL | use m::Tr1 as _; //~ WARN unused import
  | ^^^^^^^^^^^
  |
 note: lint level defined here
- --> $DIR/basic.rs:15:9
+ --> $DIR/basic.rs:14:9
  |
 LL | #![warn(unused_imports, unused_extern_crates)]
  | ^^^^^^^^^^^^^^
 
 warning: unused import: `S as _`
- --> $DIR/basic.rs:38:9
+ --> $DIR/basic.rs:37:9
  |
 LL | use S as _; //~ WARN unused import
  | ^^^^^^

src/test/ui/rfc-2166-underscore-imports/basic.rs

@@ -1,8 +1,6 @@
 // compile-pass
 // aux-build:duplicate.rs
 
-#![feature(underscore_imports)]
-
 extern crate duplicate;
 
 #[duplicate::duplicate]

src/test/ui/rfc-2166-underscore-imports/basic.stderr

@@ -1,6 +1,5 @@
 // edition:2018
 
-#![feature(underscore_imports)]
 #![deny(unused_imports)]
 
 mod multi_segment {

src/test/ui/rfc-2166-underscore-imports/duplicate.rs

@@ -1,17 +1,17 @@
 error: unused import: `core::any`
- --> $DIR/unused-2018.rs:7:9
+ --> $DIR/unused-2018.rs:6:9
  |
 LL | use core::any; //~ ERROR unused import: `core::any`
  | ^^^^^^^^^
  |
 note: lint level defined here
- --> $DIR/unused-2018.rs:4:9
+ --> $DIR/unused-2018.rs:3:9
  |
 LL | #![deny(unused_imports)]
  | ^^^^^^^^^^^^^^
 
 error: unused import: `core`
- --> $DIR/unused-2018.rs:11:9
+ --> $DIR/unused-2018.rs:10:9
  |
 LL | use core; //~ ERROR unused import: `core`
  | ^^^^