Auto merge of rust-lang#97304 - Dylan-DPC:rollup-qxrfddc, r=Dylan-DPC

Rollup of 5 pull requests

Successful merges:

 - rust-lang#97087 (Clarify slice and Vec iteration order)
 - rust-lang#97254 (Remove feature: `crate` visibility modifier)
 - rust-lang#97271 (Add regression test for rust-lang#91949)
 - rust-lang#97294 (std::time : fix variable name in the doc)
 - rust-lang#97303 (Fix some typos in arg checking algorithm)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_ast/src/ast.rs

@@ -2552,15 +2552,6 @@ impl PolyTraitRef {
     }
 }
 
-#[derive(Copy, Clone, Encodable, Decodable, Debug, HashStable_Generic)]
-pub enum CrateSugar {
-    /// Source is `pub(crate)`.
-    PubCrate,
-
-    /// Source is (just) `crate`.
-    JustCrate,
-}
-
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub struct Visibility {
     pub kind: VisibilityKind,
@@ -2571,7 +2562,6 @@ pub struct Visibility {
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub enum VisibilityKind {
     Public,
-    Crate(CrateSugar),
     Restricted { path: P<Path>, id: NodeId },
     Inherited,
 }

compiler/rustc_ast/src/mut_visit.rs

@@ -1469,7 +1469,7 @@ pub fn noop_flat_map_stmt_kind<T: MutVisitor>(
 
 pub fn noop_visit_vis<T: MutVisitor>(visibility: &mut Visibility, vis: &mut T) {
     match &mut visibility.kind {
-        VisibilityKind::Public | VisibilityKind::Crate(_) | VisibilityKind::Inherited => {}
+        VisibilityKind::Public | VisibilityKind::Inherited => {}
         VisibilityKind::Restricted { path, id } => {
             vis.visit_path(path);
             vis.visit_id(id);

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -697,18 +697,6 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
         }
         visit::walk_assoc_item(self, i, ctxt)
     }
-
-    fn visit_vis(&mut self, vis: &'a ast::Visibility) {
-        if let ast::VisibilityKind::Crate(ast::CrateSugar::JustCrate) = vis.kind {
-            gate_feature_post!(
-                &self,
-                crate_visibility_modifier,
-                vis.span,
-                "`crate` visibility modifier is experimental"
-            );
-        }
-        visit::walk_vis(self, vis)
-    }
 }
 
 pub fn check_crate(krate: &ast::Crate, sess: &Session) {
@@ -770,7 +758,6 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session) {
 
     gate_all!(trait_alias, "trait aliases are experimental");
     gate_all!(associated_type_bounds, "associated type bounds are unstable");
-    gate_all!(crate_visibility_modifier, "`crate` visibility modifier is experimental");
     gate_all!(decl_macro, "`macro` is experimental");
     gate_all!(box_patterns, "box pattern syntax is experimental");
     gate_all!(exclusive_range_pattern, "exclusive range pattern syntax is experimental");

compiler/rustc_ast_pretty/src/pprust/state/item.rs

@@ -403,13 +403,9 @@ impl<'a> State<'a> {
     pub(crate) fn print_visibility(&mut self, vis: &ast::Visibility) {
         match vis.kind {
             ast::VisibilityKind::Public => self.word_nbsp("pub"),
-            ast::VisibilityKind::Crate(sugar) => match sugar {
-                ast::CrateSugar::PubCrate => self.word_nbsp("pub(crate)"),
-                ast::CrateSugar::JustCrate => self.word_nbsp("crate"),
-            },
             ast::VisibilityKind::Restricted { ref path, .. } => {
                 let path = Self::to_string(|s| s.print_path(path, false, 0));
-                if path == "self" || path == "super" {
+                if path == "crate" || path == "self" || path == "super" {
                     self.word_nbsp(format!("pub({})", path))
                 } else {
                     self.word_nbsp(format!("pub(in {})", path))

compiler/rustc_feature/src/active.rs

@@ -351,8 +351,6 @@ declare_features! (
     (active, const_trait_impl, "1.42.0", Some(67792), None),
     /// Allows the `?` operator in const contexts.
     (active, const_try, "1.56.0", Some(74935), None),
-    /// Allows using `crate` as visibility modifier, synonymous with `pub(crate)`.
-    (active, crate_visibility_modifier, "1.23.0", Some(53120), None),
     /// Allows non-builtin attributes in inner attribute position.
     (active, custom_inner_attributes, "1.30.0", Some(54726), None),
     /// Allows custom test frameworks with `#![test_runner]` and `#[test_case]`.

compiler/rustc_feature/src/removed.rs

@@ -72,6 +72,8 @@ declare_features! (
     /// Allows `T: ?const Trait` syntax in bounds.
     (removed, const_trait_bound_opt_out, "1.42.0", Some(67794), None,
      Some("Removed in favor of `~const` bound in #![feature(const_trait_impl)]")),
+    /// Allows using `crate` as visibility modifier, synonymous with `pub(crate)`.
+    (removed, crate_visibility_modifier, "1.63.0", Some(53120), None, Some("removed in favor of `pub(crate)`")),
     /// Allows using custom attributes (RFC 572).
     (removed, custom_attribute, "1.0.0", Some(29642), None,
      Some("removed in favor of `#![register_tool]` and `#![register_attr]`")),

compiler/rustc_lint/src/builtin.rs

@@ -1372,17 +1372,11 @@ impl UnreachablePub {
             let def_span = cx.tcx.sess.source_map().guess_head_span(span);
             cx.struct_span_lint(UNREACHABLE_PUB, def_span, |lint| {
                 let mut err = lint.build(&format!("unreachable `pub` {}", what));
-                let replacement = if cx.tcx.features().crate_visibility_modifier {
-                    "crate"
-                } else {
-                    "pub(crate)"
-                }
-                .to_owned();
 
                 err.span_suggestion(
                     vis_span,
                     "consider restricting its visibility",
-                    replacement,
+                    "pub(crate)".to_owned(),
                     applicability,
                 );
                 if exportable {

compiler/rustc_parse/src/parser/item.rs

@@ -302,8 +302,7 @@ impl<'a> Parser<'a> {
 
     /// When parsing a statement, would the start of a path be an item?
     pub(super) fn is_path_start_item(&mut self) -> bool {
-        self.is_crate_vis() // no: `crate::b`, yes: `crate $item`
-        || self.is_kw_followed_by_ident(kw::Union) // no: `union::b`, yes: `union U { .. }`
+        self.is_kw_followed_by_ident(kw::Union) // no: `union::b`, yes: `union U { .. }`
         || self.check_auto_or_unsafe_trait_item() // no: `auto::b`, yes: `auto trait X { .. }`
         || self.is_async_fn() // no(2015): `async::b`, yes: `async fn`
         || matches!(self.is_macro_rules_item(), IsMacroRulesItem::Yes{..}) // no: `macro_rules::b`, yes: `macro_rules! mac`

compiler/rustc_parse/src/parser/mod.rs

@@ -25,7 +25,7 @@ use rustc_ast::tokenstream::{self, DelimSpan, Spacing};
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_ast::AttrId;
 use rustc_ast::DUMMY_NODE_ID;
-use rustc_ast::{self as ast, AnonConst, AttrStyle, AttrVec, Const, CrateSugar, Extern};
+use rustc_ast::{self as ast, AnonConst, AttrStyle, AttrVec, Const, Extern};
 use rustc_ast::{Async, Expr, ExprKind, MacArgs, MacArgsEq, MacDelimiter, Mutability, StrLit};
 use rustc_ast::{HasAttrs, HasTokens, Unsafe, Visibility, VisibilityKind};
 use rustc_ast_pretty::pprust;
@@ -1245,30 +1245,15 @@ impl<'a> Parser<'a> {
         res
     }
 
-    fn is_crate_vis(&self) -> bool {
-        self.token.is_keyword(kw::Crate) && self.look_ahead(1, |t| t != &token::ModSep)
-    }
-
-    /// Parses `pub`, `pub(crate)` and `pub(in path)` plus shortcuts `crate` for `pub(crate)`,
-    /// `pub(self)` for `pub(in self)` and `pub(super)` for `pub(in super)`.
+    /// Parses `pub` and `pub(in path)` plus shortcuts `pub(crate)` for `pub(in crate)`, `pub(self)`
+    /// for `pub(in self)` and `pub(super)` for `pub(in super)`.
     /// If the following element can't be a tuple (i.e., it's a function definition), then
     /// it's not a tuple struct field), and the contents within the parentheses aren't valid,
     /// so emit a proper diagnostic.
     // Public for rustfmt usage.
     pub fn parse_visibility(&mut self, fbt: FollowedByType) -> PResult<'a, Visibility> {
         maybe_whole!(self, NtVis, |x| x.into_inner());
 
-        self.expected_tokens.push(TokenType::Keyword(kw::Crate));
-        if self.is_crate_vis() {
-            self.bump(); // `crate`
-            self.sess.gated_spans.gate(sym::crate_visibility_modifier, self.prev_token.span);
-            return Ok(Visibility {
-                span: self.prev_token.span,
-                kind: VisibilityKind::Crate(CrateSugar::JustCrate),
-                tokens: None,
-            });
-        }
-
         if !self.eat_keyword(kw::Pub) {
             // We need a span for our `Spanned<VisibilityKind>`, but there's inherently no
             // keyword to grab a span from for inherited visibility; an empty span at the
@@ -1286,20 +1271,7 @@ impl<'a> Parser<'a> {
             // `()` or a tuple might be allowed. For example, `struct Struct(pub (), pub (usize));`.
             // Because of this, we only `bump` the `(` if we're assured it is appropriate to do so
             // by the following tokens.
-            if self.is_keyword_ahead(1, &[kw::Crate]) && self.look_ahead(2, |t| t != &token::ModSep)
-            // account for `pub(crate::foo)`
-            {
-                // Parse `pub(crate)`.
-                self.bump(); // `(`
-                self.bump(); // `crate`
-                self.expect(&token::CloseDelim(Delimiter::Parenthesis))?; // `)`
-                let vis = VisibilityKind::Crate(CrateSugar::PubCrate);
-                return Ok(Visibility {
-                    span: lo.to(self.prev_token.span),
-                    kind: vis,
-                    tokens: None,
-                });
-            } else if self.is_keyword_ahead(1, &[kw::In]) {
+            if self.is_keyword_ahead(1, &[kw::In]) {
                 // Parse `pub(in path)`.
                 self.bump(); // `(`
                 self.bump(); // `in`
@@ -1312,11 +1284,11 @@ impl<'a> Parser<'a> {
                     tokens: None,
                 });
             } else if self.look_ahead(2, |t| t == &token::CloseDelim(Delimiter::Parenthesis))
-                && self.is_keyword_ahead(1, &[kw::Super, kw::SelfLower])
+                && self.is_keyword_ahead(1, &[kw::Crate, kw::Super, kw::SelfLower])
             {
-                // Parse `pub(self)` or `pub(super)`.
+                // Parse `pub(crate)`, `pub(self)`, or `pub(super)`.
                 self.bump(); // `(`
-                let path = self.parse_path(PathStyle::Mod)?; // `super`/`self`
+                let path = self.parse_path(PathStyle::Mod)?; // `crate`/`super`/`self`
                 self.expect(&token::CloseDelim(Delimiter::Parenthesis))?; // `)`
                 let vis = VisibilityKind::Restricted { path: P(path), id: ast::DUMMY_NODE_ID };
                 return Ok(Visibility {

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -249,9 +249,6 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
         let parent_scope = &self.parent_scope;
         match vis.kind {
             ast::VisibilityKind::Public => Ok(ty::Visibility::Public),
-            ast::VisibilityKind::Crate(..) => {
-                Ok(ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id()))
-            }
             ast::VisibilityKind::Inherited => {
                 Ok(match self.parent_scope.module.kind {
                     // Any inherited visibility resolved directly inside an enum or trait

compiler/rustc_typeck/src/check/fn_ctxt/checks.rs

@@ -768,7 +768,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 let second_input_ty =
                                     self.resolve_vars_if_possible(expected_input_tys[second_idx]);
                                 let third_input_ty =
-                                    self.resolve_vars_if_possible(expected_input_tys[second_idx]);
+                                    self.resolve_vars_if_possible(expected_input_tys[third_idx]);
                                 let span = if third_idx < provided_arg_count {
                                     let first_arg_span = provided_args[first_idx].span;
                                     let third_arg_span = provided_args[third_idx].span;
@@ -809,16 +809,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             }
                             missing_idxs => {
                                 let first_idx = *missing_idxs.first().unwrap();
-                                let second_idx = *missing_idxs.last().unwrap();
+                                let last_idx = *missing_idxs.last().unwrap();
                                 // NOTE: Because we might be re-arranging arguments, might have extra arguments, etc.
                                 // It's hard to *really* know where we should provide this error label, so this is a
                                 // decent heuristic
-                                let span = if first_idx < provided_arg_count {
+                                let span = if last_idx < provided_arg_count {
                                     let first_arg_span = provided_args[first_idx].span;
-                                    let second_arg_span = provided_args[second_idx].span;
+                                    let last_arg_span = provided_args[last_idx].span;
                                     Span::new(
                                         first_arg_span.lo(),
-                                        second_arg_span.hi(),
+                                        last_arg_span.hi(),
                                         first_arg_span.ctxt(),
                                         None,
                                     )

library/alloc/src/vec/mod.rs

@@ -2626,10 +2626,13 @@ impl<T, A: Allocator> IntoIterator for Vec<T, A> {
     ///
     /// ```
     /// let v = vec!["a".to_string(), "b".to_string()];
-    /// for s in v.into_iter() {
-    ///     // s has type String, not &String
-    ///     println!("{s}");
-    /// }
+    /// let mut v_iter = v.into_iter();
+    ///
+    /// let first_element: Option<String> = v_iter.next();
+    ///
+    /// assert_eq!(first_element, Some("a".to_string()));
+    /// assert_eq!(v_iter.next(), Some("b".to_string()));
+    /// assert_eq!(v_iter.next(), None);
     /// ```
     #[inline]
     fn into_iter(self) -> IntoIter<T, A> {

library/core/src/slice/mod.rs

@@ -716,6 +716,8 @@ impl<T> [T] {
 
     /// Returns an iterator over the slice.
     ///
+    /// The iterator yields all items from start to end.
+    ///
     /// # Examples
     ///
     /// ```
@@ -735,6 +737,8 @@ impl<T> [T] {
 
     /// Returns an iterator that allows modifying each value.
     ///
+    /// The iterator yields all items from start to end.
+    ///
     /// # Examples
     ///
     /// ```

library/std/src/time.rs

@@ -95,8 +95,8 @@ pub use core::time::FromFloatSecsError;
 /// use std::time::{Instant, Duration};
 ///
 /// let now = Instant::now();
-/// let max_nanoseconds = u64::MAX / 1_000_000_000;
-/// let duration = Duration::new(max_nanoseconds, 0);
+/// let max_seconds = u64::MAX / 1_000_000_000;
+/// let duration = Duration::new(max_seconds, 0);
 /// println!("{:?}", now + duration);
 /// ```
 ///

src/doc/unstable-book/src/language-features/crate-visibility-modifier.md

@@ -0,0 +1,6 @@
+fn main() {
+    g((), ());
+    //~^ ERROR this function takes 6 arguments but 2 arguments were supplied
+}
+
+pub fn g(a1: (), a2: bool, a3: bool, a4: bool, a5: bool, a6: ()) -> () {}

src/test/ui/argument-suggestions/issue-97197.rs

@@ -0,0 +1,19 @@
+error[E0061]: this function takes 6 arguments but 2 arguments were supplied
+  --> $DIR/issue-97197.rs:2:5
+   |
+LL |     g((), ());
+   |     ^-------- multiple arguments are missing
+   |
+note: function defined here
+  --> $DIR/issue-97197.rs:6:8
+   |
+LL | pub fn g(a1: (), a2: bool, a3: bool, a4: bool, a5: bool, a6: ()) -> () {}
+   |        ^ ------  --------  --------  --------  --------  ------
+help: provide the arguments
+   |
+LL |     g((), {bool}, {bool}, {bool}, {bool}, ());
+   |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0061`.

src/test/ui/argument-suggestions/issue-97197.stderr

@@ -293,7 +293,7 @@ error[E0061]: this function takes 5 arguments but 2 arguments were supplied
   --> $DIR/missing_arguments.rs:39:3
    |
 LL |   complex(   1,                     ""   );
-   |   ^^^^^^^--------------------------------- three arguments of type `f32`, `i32`, and `i32` are missing
+   |   ^^^^^^^--------------------------------- three arguments of type `f32`, `i32`, and `f32` are missing
    |
 note: function defined here
   --> $DIR/missing_arguments.rs:7:4

src/test/ui/argument-suggestions/missing_arguments.stderr

@@ -861,10 +861,8 @@ fn test_vis() {
     // VisibilityKind::Public
     assert_eq!(stringify_vis!(pub), "pub ");
 
-    // VisibilityKind::Crate
-    assert_eq!(stringify_vis!(crate), "crate ");
-
     // VisibilityKind::Restricted
+    assert_eq!(stringify_vis!(pub(crate)), "pub(crate) ");
     assert_eq!(stringify_vis!(pub(self)), "pub(self) ");
     assert_eq!(stringify_vis!(pub(super)), "pub(super) ");
     assert_eq!(stringify_vis!(pub(in self)), "pub(self) ");