Auto merge of #73528 - Manishearth:rollup-7djz8nd, r=Manishearth

Rollup of 16 pull requests

Successful merges:

 - #71420 (Specialization is unsound)
 - #71899 (Refactor `try_find` a little)
 - #72689 (add str to common types)
 - #72791 (update coerce docs and unify relevant tests)
 - #72934 (forbid mutable references in all constant contexts except for const-fns)
 - #73027 (Make `need_type_info_err` more conservative)
 - #73347 (Diagnose use of incompatible sanitizers)
 - #73359 (shim.rs: avoid creating `Call` terminators calling `Self`)
 - #73399 (Clean up E0668 explanation)
 - #73436 (Clean up E0670 explanation)
 - #73440 (Add src/librustdoc as an alias for src/tools/rustdoc)
 - #73442 (pretty/mir: const value enums with no variants)
 - #73452 (Unify region variables when projecting associated types)
 - #73458 (Use alloc::Layout in DroplessArena API)
 - #73484 (Update the doc for std::prelude to the correct behavior)
 - #73506 (Bump Rustfmt and RLS)

Failed merges:

r? @ghost

2 files changed, 19 insertions, 12 deletions

diff --git a/src/libcore/iter/traits/iterator.rs b/src/libcore/iter/traits/iterator.rs
index fbfcdc3c1a9..530cf881f29 100644
--- a/src/libcore/iter/traits/iterator.rs
+++ b/src/libcore/iter/traits/iterator.rs
@@ -2265,7 +2265,7 @@ pub trait Iterator {
     }
 
     /// Applies function to the elements of iterator and returns
-    /// the first non-none result or the first error.
+    /// the first true result or the first error.
     ///
     /// # Examples
     ///
@@ -2286,19 +2286,26 @@ pub trait Iterator {
     /// ```
     #[inline]
     #[unstable(feature = "try_find", reason = "new API", issue = "63178")]
-    fn try_find<F, E, R>(&mut self, mut f: F) -> Result<Option<Self::Item>, E>
+    fn try_find<F, R>(&mut self, f: F) -> Result<Option<Self::Item>, R::Error>
     where
         Self: Sized,
         F: FnMut(&Self::Item) -> R,
-        R: Try<Ok = bool, Error = E>,
-    {
-        self.try_fold((), move |(), x| match f(&x).into_result() {
-            Ok(false) => LoopState::Continue(()),
-            Ok(true) => LoopState::Break(Ok(x)),
-            Err(x) => LoopState::Break(Err(x)),
-        })
-        .break_value()
-        .transpose()
+        R: Try<Ok = bool>,
+    {
+        #[inline]
+        fn check<F, T, R>(mut f: F) -> impl FnMut((), T) -> LoopState<(), Result<T, R::Error>>
+        where
+            F: FnMut(&T) -> R,
+            R: Try<Ok = bool>,
+        {
+            move |(), x| match f(&x).into_result() {
+                Ok(false) => LoopState::Continue(()),
+                Ok(true) => LoopState::Break(Ok(x)),
+                Err(x) => LoopState::Break(Err(x)),
+            }
+        }
+
+        self.try_fold((), check(f)).break_value().transpose()
     }
 
     /// Searches for an element in an iterator, returning its index.
diff --git a/src/libcore/tests/lib.rs b/src/libcore/tests/lib.rs
index 37ebf411280..4e55452a4c3 100644
--- a/src/libcore/tests/lib.rs
+++ b/src/libcore/tests/lib.rs
@@ -19,7 +19,7 @@
 #![feature(raw)]
 #![feature(sort_internals)]
 #![feature(slice_partition_at_index)]
-#![feature(specialization)]
+#![feature(min_specialization)]
 #![feature(step_trait)]
 #![feature(step_trait_ext)]
 #![feature(str_internals)]