Auto merge of rust-lang#108228 - Dylan-DPC:rollup-i9t13qu, r=Dylan-DPC

Rollup of 7 pull requests

Successful merges:

 - rust-lang#104659 (reflow the stack size story)
 - rust-lang#106933 (Update documentation of select_nth_unstable and select_nth_unstable_by to state O(n^2) complexity)
 - rust-lang#107783 (rustdoc: simplify DOM for `.item-table`)
 - rust-lang#107951 (resolve: Fix doc links referring to other crates when documenting proc macro crates directly)
 - rust-lang#108130 ("Basic usage" is redundant for there is just one example)
 - rust-lang#108146 (rustdoc: hide `reference` methods in search index)
 - rust-lang#108189 (Fix some more `non_lifetime_binders` stuff with higher-ranked trait bounds)

Failed merges:

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

compiler/rustc_infer/src/infer/canonical/canonicalizer.rs

@@ -418,10 +418,15 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                 bug!("encountered a fresh type during canonicalization")
             }
 
-            ty::Placeholder(placeholder) => self.canonicalize_ty_var(
-                CanonicalVarInfo { kind: CanonicalVarKind::PlaceholderTy(placeholder) },
-                t,
-            ),
+            ty::Placeholder(mut placeholder) => {
+                if !self.canonicalize_mode.preserve_universes() {
+                    placeholder.universe = ty::UniverseIndex::ROOT;
+                }
+                self.canonicalize_ty_var(
+                    CanonicalVarInfo { kind: CanonicalVarKind::PlaceholderTy(placeholder) },
+                    t,
+                )
+            }
 
             ty::Bound(debruijn, _) => {
                 if debruijn >= self.binder_index {

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -735,7 +735,10 @@ pub trait PrettyPrinter<'tcx>:
                     p!(print(data))
                 }
             }
-            ty::Placeholder(placeholder) => p!(write("Placeholder({:?})", placeholder)),
+            ty::Placeholder(placeholder) => match placeholder.name {
+                ty::BoundTyKind::Anon(_) => p!(write("Placeholder({:?})", placeholder)),
+                ty::BoundTyKind::Param(_, name) => p!(write("{}", name)),
+            },
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) => {
                 // We use verbose printing in 'NO_QUERIES' mode, to
                 // avoid needing to call `predicates_of`. This should

compiler/rustc_resolve/src/late.rs

@@ -4211,7 +4211,8 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
                 if let Some(res) = res
                     && let Some(def_id) = res.opt_def_id()
                     && !def_id.is_local()
-                    && self.r.session.crate_types().contains(&CrateType::ProcMacro) {
+                    && self.r.session.crate_types().contains(&CrateType::ProcMacro)
+                    && matches!(self.r.session.opts.resolve_doc_links, ResolveDocLinks::ExportedMetadata) {
                     // Encoding foreign def ids in proc macro crate metadata will ICE.
                     return None;
                 }
@@ -4281,6 +4282,10 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
                         .filter_map(|tr| {
                             if !tr.def_id.is_local()
                                 && self.r.session.crate_types().contains(&CrateType::ProcMacro)
+                                && matches!(
+                                    self.r.session.opts.resolve_doc_links,
+                                    ResolveDocLinks::ExportedMetadata
+                                )
                             {
                                 // Encoding foreign def ids in proc macro crate metadata will ICE.
                                 return None;

compiler/rustc_trait_selection/src/traits/select/mod.rs

@@ -2148,12 +2148,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 }))
             }
 
-            ty::Alias(..) | ty::Param(_) => None,
+            ty::Alias(..) | ty::Param(_) | ty::Placeholder(..) => None,
             ty::Infer(ty::TyVar(_)) => Ambiguous,
 
-            ty::Placeholder(..)
-            | ty::Bound(..)
-            | ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => {
+            // We can make this an ICE if/once we actually instantiate the trait obligation.
+            ty::Bound(..) => None,
+
+            ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => {
                 bug!("asked to assemble builtin bounds of unexpected type: {:?}", self_ty);
             }
         }

library/core/src/result.rs

@@ -525,8 +525,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<i32, &str> = Ok(-3);
     /// assert_eq!(x.is_ok(), true);
@@ -572,8 +570,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<i32, &str> = Ok(-3);
     /// assert_eq!(x.is_err(), false);
@@ -627,8 +623,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(2);
     /// assert_eq!(x.ok(), Some(2));
@@ -658,8 +652,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(2);
     /// assert_eq!(x.err(), None);
@@ -693,8 +685,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(2);
     /// assert_eq!(x.as_ref(), Ok(&2));
@@ -716,8 +706,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// fn mutate(r: &mut Result<i32, i32>) {
     ///     match r.as_mut() {
@@ -812,8 +800,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let k = 21;
     ///
@@ -841,8 +827,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// fn stringify(x: u32) -> String { format!("error code: {x}") }
     ///
@@ -968,8 +952,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(7);
     /// assert_eq!(x.iter().next(), Some(&7));
@@ -989,8 +971,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let mut x: Result<u32, &str> = Ok(7);
     /// match x.iter_mut().next() {
@@ -1031,8 +1011,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```should_panic
     /// let x: Result<u32, &str> = Err("emergency failure");
     /// x.expect("Testing expect"); // panics with `Testing expect: emergency failure`
@@ -1160,8 +1138,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```should_panic
     /// let x: Result<u32, &str> = Ok(10);
     /// x.expect_err("Testing expect_err"); // panics with `Testing expect_err: 10`
@@ -1222,8 +1198,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// # #![feature(never_type)]
     /// # #![feature(unwrap_infallible)]
@@ -1259,8 +1233,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// # #![feature(never_type)]
     /// # #![feature(unwrap_infallible)]
@@ -1298,8 +1270,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(2);
     /// let y: Result<&str, &str> = Err("late error");
@@ -1383,8 +1353,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(2);
     /// let y: Result<u32, &str> = Err("late error");
@@ -1426,8 +1394,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// fn sq(x: u32) -> Result<u32, u32> { Ok(x * x) }
     /// fn err(x: u32) -> Result<u32, u32> { Err(x) }
@@ -1456,8 +1422,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let default = 2;
     /// let x: Result<u32, &str> = Ok(9);
@@ -1487,8 +1451,6 @@ impl<T, E> Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// fn count(x: &str) -> usize { x.len() }
     ///
@@ -1752,8 +1714,6 @@ impl<T, E> Result<Result<T, E>, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// #![feature(result_flattening)]
     /// let x: Result<Result<&'static str, u32>, u32> = Ok(Ok("hello"));
@@ -1842,8 +1802,6 @@ impl<T, E> IntoIterator for Result<T, E> {
     ///
     /// # Examples
     ///
-    /// Basic usage:
-    ///
     /// ```
     /// let x: Result<u32, &str> = Ok(5);
     /// let v: Vec<u32> = x.into_iter().collect();

library/core/src/slice/mod.rs

@@ -2730,8 +2730,10 @@ impl<T> [T] {
     /// This reordering has the additional property that any value at position `i < index` will be
     /// less than or equal to any value at a position `j > index`. Additionally, this reordering is
     /// unstable (i.e. any number of equal elements may end up at position `index`), in-place
-    /// (i.e. does not allocate), and *O*(*n*) worst-case. This function is also/ known as "kth
-    /// element" in other libraries. It returns a triplet of the following from the reordered slice:
+    /// (i.e. does not allocate), and *O*(*n*) on average. The worst-case performance is *O*(*n* log *n*).
+    /// This function is also known as "kth element" in other libraries.
+    ///
+    /// It returns a triplet of the following from the reordered slice:
     /// the subslice prior to `index`, the element at `index`, and the subslice after `index`;
     /// accordingly, the values in those two subslices will respectively all be less-than-or-equal-to
     /// and greater-than-or-equal-to the value of the element at `index`.
@@ -2777,8 +2779,11 @@ impl<T> [T] {
     /// This reordering has the additional property that any value at position `i < index` will be
     /// less than or equal to any value at a position `j > index` using the comparator function.
     /// Additionally, this reordering is unstable (i.e. any number of equal elements may end up at
-    /// position `index`), in-place (i.e. does not allocate), and *O*(*n*) worst-case. This function
-    /// is also known as "kth element" in other libraries. It returns a triplet of the following from
+    /// position `index`), in-place (i.e. does not allocate), and *O*(*n*) on average.
+    /// The worst-case performance is *O*(*n* log *n*). This function is also known as
+    /// "kth element" in other libraries.
+    ///
+    /// It returns a triplet of the following from
     /// the slice reordered according to the provided comparator function: the subslice prior to
     /// `index`, the element at `index`, and the subslice after `index`; accordingly, the values in
     /// those two subslices will respectively all be less-than-or-equal-to and greater-than-or-equal-to
@@ -2829,8 +2834,11 @@ impl<T> [T] {
     /// This reordering has the additional property that any value at position `i < index` will be
     /// less than or equal to any value at a position `j > index` using the key extraction function.
     /// Additionally, this reordering is unstable (i.e. any number of equal elements may end up at
-    /// position `index`), in-place (i.e. does not allocate), and *O*(*n*) worst-case. This function
-    /// is also known as "kth element" in other libraries. It returns a triplet of the following from
+    /// position `index`), in-place (i.e. does not allocate), and *O*(*n*) on average.
+    /// The worst-case performance is *O*(*n* log *n*).
+    /// This function is also known as "kth element" in other libraries.
+    ///
+    /// It returns a triplet of the following from
     /// the slice reordered according to the provided key extraction function: the subslice prior to
     /// `index`, the element at `index`, and the subslice after `index`; accordingly, the values in
     /// those two subslices will respectively all be less-than-or-equal-to and greater-than-or-equal-to

library/std/src/thread/mod.rs

@@ -124,8 +124,10 @@
 //!
 //! ## Stack size
 //!
-//! The default stack size is platform-dependent and subject to change. Currently it is 2MB on all
-//! Tier-1 platforms. There are two ways to manually specify the stack size for spawned threads:
+//! The default stack size is platform-dependent and subject to change.
+//! Currently, it is 2 MiB on all Tier-1 platforms.
+//!
+//! There are two ways to manually specify the stack size for spawned threads:
 //!
 //! * Build the thread with [`Builder`] and pass the desired stack size to [`Builder::stack_size`].
 //! * Set the `RUST_MIN_STACK` environment variable to an integer representing the desired stack

src/librustdoc/formats/cache.rs

@@ -287,6 +287,16 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
                     } else {
                         let last = self.cache.parent_stack.last().expect("parent_stack is empty 2");
                         let did = match &*last {
+                            ParentStackItem::Impl {
+                                // impl Trait for &T { fn method(self); }
+                                //
+                                // When generating a function index with the above shape, we want it
+                                // associated with `T`, not with the primitive reference type. It should
+                                // show up as `T::method`, rather than `reference::method`, in the search
+                                // results page.
+                                for_: clean::Type::BorrowedRef { type_, .. },
+                                ..
+                            } => type_.def_id(&self.cache),
                             ParentStackItem::Impl { for_, .. } => for_.def_id(&self.cache),
                             ParentStackItem::Type(item_id) => item_id.as_def_id(),
                         };

src/librustdoc/html/render/print_item.rs

@@ -39,10 +39,10 @@ use crate::html::{highlight, static_files};
 use askama::Template;
 use itertools::Itertools;
 
-const ITEM_TABLE_OPEN: &str = "<div class=\"item-table\">";
-const ITEM_TABLE_CLOSE: &str = "</div>";
-const ITEM_TABLE_ROW_OPEN: &str = "<div class=\"item-row\">";
-const ITEM_TABLE_ROW_CLOSE: &str = "</div>";
+const ITEM_TABLE_OPEN: &str = "<ul class=\"item-table\">";
+const ITEM_TABLE_CLOSE: &str = "</ul>";
+const ITEM_TABLE_ROW_OPEN: &str = "<li>";
+const ITEM_TABLE_ROW_CLOSE: &str = "</li>";
 
 // A component in a `use` path, like `string` in std::string::ToString
 struct PathComponent {
@@ -338,14 +338,14 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                 match *src {
                     Some(src) => write!(
                         w,
-                        "<div class=\"item-left\"><code>{}extern crate {} as {};",
+                        "<div class=\"item-name\"><code>{}extern crate {} as {};",
                         visibility_print_with_space(myitem.visibility(tcx), myitem.item_id, cx),
                         anchor(myitem.item_id.expect_def_id(), src, cx),
                         myitem.name.unwrap(),
                     ),
                     None => write!(
                         w,
-                        "<div class=\"item-left\"><code>{}extern crate {};",
+                        "<div class=\"item-name\"><code>{}extern crate {};",
                         visibility_print_with_space(myitem.visibility(tcx), myitem.item_id, cx),
                         anchor(myitem.item_id.expect_def_id(), myitem.name.unwrap(), cx),
                     ),
@@ -384,11 +384,11 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                 let (stab_tags_before, stab_tags_after) = if stab_tags.is_empty() {
                     ("", "")
                 } else {
-                    ("<div class=\"item-right docblock-short\">", "</div>")
+                    ("<div class=\"desc docblock-short\">", "</div>")
                 };
                 write!(
                     w,
-                    "<div class=\"item-left\"{id}>\
+                    "<div class=\"item-name\"{id}>\
                          <code>{vis}{imp}</code>\
                      </div>\
                      {stab_tags_before}{stab_tags}{stab_tags_after}",
@@ -426,11 +426,11 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                 let (docs_before, docs_after) = if docs.is_empty() {
                     ("", "")
                 } else {
-                    ("<div class=\"item-right docblock-short\">", "</div>")
+                    ("<div class=\"desc docblock-short\">", "</div>")
                 };
                 write!(
                     w,
-                    "<div class=\"item-left\">\
+                    "<div class=\"item-name\">\
                         <a class=\"{class}\" href=\"{href}\" title=\"{title}\">{name}</a>\
                         {visibility_emoji}\
                         {unsafety_flag}\