Auto merge of #148075 - cuviper:beta-next, r=cuviper

[beta] backports

- Revert constification of `AsRef for Cow` due to inference failure #148011
- Revert constification of `Borrow` and `Deref for Cow` due to inference failure #148016
- Revert "fix: Filter suggestion parts that match existing code" #148043
- Revert "feat: implement `hash_map!` macro" #148049
- fix panic when rustc tries to reduce intermediate filenames len with utf8 #148018

r? cuviper

Author: bors

compiler/rustc_errors/src/diagnostic.rs

@@ -945,6 +945,11 @@ impl<'a, G: EmissionGuarantee> Diag<'a, G> {
             None,
             "Span must not be empty and have no suggestion",
         );
+        debug_assert_eq!(
+            parts.array_windows().find(|[a, b]| a.span.overlaps(b.span)),
+            None,
+            "suggestion must not have overlapping parts",
+        );
 
         self.push_suggestion(CodeSuggestion {
             substitutions: vec![Substitution { parts }],

compiler/rustc_errors/src/emitter.rs

@@ -2354,6 +2354,7 @@ impl HumanEmitter {
                         .sum();
                     let underline_start = (span_start_pos + start) as isize + offset;
                     let underline_end = (span_start_pos + start + sub_len) as isize + offset;
+                    assert!(underline_start >= 0 && underline_end >= 0);
                     let padding: usize = max_line_num_len + 3;
                     for p in underline_start..underline_end {
                         if let DisplaySuggestion::Underline = show_code_change

compiler/rustc_errors/src/lib.rs

@@ -381,17 +381,6 @@ impl CodeSuggestion {
                 // Assumption: all spans are in the same file, and all spans
                 // are disjoint. Sort in ascending order.
                 substitution.parts.sort_by_key(|part| part.span.lo());
-                // Verify the assumption that all spans are disjoint
-                assert_eq!(
-                    substitution.parts.array_windows().find(|[a, b]| a.span.overlaps(b.span)),
-                    None,
-                    "all spans must be disjoint",
-                );
-
-                // Account for cases where we are suggesting the same code that's already
-                // there. This shouldn't happen often, but in some cases for multipart
-                // suggestions it's much easier to handle it here than in the origin.
-                substitution.parts.retain(|p| is_different(sm, &p.snippet, p.span));
 
                 // Find the bounding span.
                 let lo = substitution.parts.iter().map(|part| part.span.lo()).min()?;
@@ -481,12 +470,16 @@ impl CodeSuggestion {
                             _ => 1,
                         })
                         .sum();
-
-                    line_highlight.push(SubstitutionHighlight {
-                        start: (cur_lo.col.0 as isize + acc) as usize,
-                        end: (cur_lo.col.0 as isize + acc + len) as usize,
-                    });
-
+                    if !is_different(sm, &part.snippet, part.span) {
+                        // Account for cases where we are suggesting the same code that's already
+                        // there. This shouldn't happen often, but in some cases for multipart
+                        // suggestions it's much easier to handle it here than in the origin.
+                    } else {
+                        line_highlight.push(SubstitutionHighlight {
+                            start: (cur_lo.col.0 as isize + acc) as usize,
+                            end: (cur_lo.col.0 as isize + acc + len) as usize,
+                        });
+                    }
                     buf.push_str(&part.snippet);
                     let cur_hi = sm.lookup_char_pos(part.span.hi());
                     // Account for the difference between the width of the current code and the

compiler/rustc_session/src/config.rs

@@ -1207,13 +1207,22 @@ fn maybe_strip_file_name(mut path: PathBuf) -> PathBuf {
     if path.file_name().map_or(0, |name| name.len()) > MAX_FILENAME_LENGTH {
         let filename = path.file_name().unwrap().to_string_lossy();
         let hash_len = 64 / 4; // Hash64 is 64 bits encoded in hex
-        let stripped_len = filename.len() - MAX_FILENAME_LENGTH + hash_len;
+        let hyphen_len = 1; // the '-' we insert between hash and suffix
+
+        // number of bytes of suffix we can keep so that "hash-<suffix>" fits
+        let allowed_suffix = MAX_FILENAME_LENGTH.saturating_sub(hash_len + hyphen_len);
+
+        // number of bytes to remove from the start
+        let stripped_bytes = filename.len().saturating_sub(allowed_suffix);
+
+        // ensure we don't cut in a middle of a char
+        let split_at = filename.ceil_char_boundary(stripped_bytes);
 
         let mut hasher = StableHasher::new();
-        filename[..stripped_len].hash(&mut hasher);
+        filename[..split_at].hash(&mut hasher);
         let hash = hasher.finish::<Hash64>();
 
-        path.set_file_name(format!("{:x}-{}", hash, &filename[stripped_len..]));
+        path.set_file_name(format!("{:x}-{}", hash, &filename[split_at..]));
     }
     path
 }

compiler/rustc_session/src/lib.rs

@@ -1,5 +1,6 @@
 // tidy-alphabetical-start
 #![allow(internal_features)]
+#![cfg_attr(bootstrap, feature(round_char_boundary))]
 #![feature(default_field_values)]
 #![feature(iter_intersperse)]
 #![feature(rustc_attrs)]

library/alloc/src/borrow.rs

@@ -16,12 +16,13 @@ use crate::fmt;
 #[cfg(not(no_global_oom_handling))]
 use crate::string::String;
 
+// FIXME(inference): const bounds removed due to inference regressions found by crater;
+//   see https://github.com/rust-lang/rust/issues/147964
+// #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-impl<'a, B: ?Sized> const Borrow<B> for Cow<'a, B>
-where
-    B: ToOwned,
-    B::Owned: [const] Borrow<B>,
+impl<'a, B: ?Sized + ToOwned> Borrow<B> for Cow<'a, B>
+// where
+//     B::Owned: [const] Borrow<B>,
 {
     fn borrow(&self) -> &B {
         &**self
@@ -327,11 +328,13 @@ impl<B: ?Sized + ToOwned> Cow<'_, B> {
     }
 }
 
+// FIXME(inference): const bounds removed due to inference regressions found by crater;
+//   see https://github.com/rust-lang/rust/issues/147964
+// #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-impl<B: ?Sized + ToOwned> const Deref for Cow<'_, B>
-where
-    B::Owned: [const] Borrow<B>,
+impl<B: ?Sized + ToOwned> Deref for Cow<'_, B>
+// where
+//     B::Owned: [const] Borrow<B>,
 {
     type Target = B;
 
@@ -441,11 +444,13 @@ where
     }
 }
 
+// FIXME(inference): const bounds removed due to inference regressions found by crater;
+//   see https://github.com/rust-lang/rust/issues/147964
+// #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-impl<T: ?Sized + ToOwned> const AsRef<T> for Cow<'_, T>
-where
-    T::Owned: [const] Borrow<T>,
+impl<T: ?Sized + ToOwned> AsRef<T> for Cow<'_, T>
+// where
+//     T::Owned: [const] Borrow<T>,
 {
     fn as_ref(&self) -> &T {
         self

library/std/src/lib.rs

@@ -294,8 +294,6 @@
 #![feature(ffi_const)]
 #![feature(formatting_options)]
 #![feature(funnel_shifts)]
-#![feature(hash_map_internals)]
-#![feature(hash_map_macro)]
 #![feature(if_let_guard)]
 #![feature(intra_doc_pointers)]
 #![feature(iter_advance_by)]

library/std/src/macros.rs

@@ -379,77 +379,3 @@ macro_rules! dbg {
         ($($crate::dbg!($val)),+,)
     };
 }
-
-#[doc(hidden)]
-#[macro_export]
-#[allow_internal_unstable(hash_map_internals)]
-#[unstable(feature = "hash_map_internals", issue = "none")]
-macro_rules! repetition_utils {
-    (@count $($tokens:tt),*) => {{
-        [$($crate::repetition_utils!(@replace $tokens => ())),*].len()
-    }};
-
-    (@replace $x:tt => $y:tt) => { $y }
-}
-
-/// Creates a [`HashMap`] containing the arguments.
-///
-/// `hash_map!` allows specifying the entries that make
-/// up the [`HashMap`] where the key and value are separated by a `=>`.
-///
-/// The entries are separated by commas with a trailing comma being allowed.
-///
-/// It is semantically equivalent to using repeated [`HashMap::insert`]
-/// on a newly created hashmap.
-///
-/// `hash_map!` will attempt to avoid repeated reallocations by
-/// using [`HashMap::with_capacity`].
-///
-/// # Examples
-///
-/// ```rust
-/// #![feature(hash_map_macro)]
-///
-/// let map = hash_map! {
-///     "key" => "value",
-///     "key1" => "value1"
-/// };
-///
-/// assert_eq!(map.get("key"), Some(&"value"));
-/// assert_eq!(map.get("key1"), Some(&"value1"));
-/// assert!(map.get("brrrrrrooooommm").is_none());
-/// ```
-///
-/// And with a trailing comma
-///
-///```rust
-/// #![feature(hash_map_macro)]
-///
-/// let map = hash_map! {
-///     "key" => "value", // notice the ,
-/// };
-///
-/// assert_eq!(map.get("key"), Some(&"value"));
-/// ```
-///
-/// The key and value are moved into the HashMap.
-///
-/// [`HashMap`]: crate::collections::HashMap
-/// [`HashMap::insert`]: crate::collections::HashMap::insert
-/// [`HashMap::with_capacity`]: crate::collections::HashMap::with_capacity
-#[macro_export]
-#[allow_internal_unstable(hash_map_internals)]
-#[unstable(feature = "hash_map_macro", issue = "144032")]
-macro_rules! hash_map {
-    () => {{
-        $crate::collections::HashMap::new()
-    }};
-
-    ( $( $key:expr => $value:expr ),* $(,)? ) => {{
-        let mut map = $crate::collections::HashMap::with_capacity(
-            const { $crate::repetition_utils!(@count $($key),*) }
-        );
-        $( map.insert($key, $value); )*
-        map
-    }}
-}

library/std/tests/ambiguous-hash_map.rs

@@ -0,0 +1,17 @@
+//! Make sure that a `std` macro `hash_map!` does not cause ambiguity
+//! with a local glob import with the same name.
+//!
+//! See regression https://github.com/rust-lang/rust/issues/147971
+
+mod module {
+    macro_rules! hash_map {
+        () => {};
+    }
+    pub(crate) use hash_map;
+}
+
+use module::*;
+
+fn main() {
+    hash_map! {}
+}

src/tools/clippy/tests/ui/bool_assert_comparison.stderr

@@ -272,8 +272,10 @@ LL |     assert_eq!(a!(), true);
    |
 help: replace it with `assert!(..)`
    |
-LL -     assert_eq!(a!(), true);
-LL +     assert!(a!());
+LL |         true
+...
+LL |
+LL ~     assert!(a!());
    |
 
 error: used `assert_eq!` with a literal bool
@@ -284,8 +286,10 @@ LL |     assert_eq!(true, b!());
    |
 help: replace it with `assert!(..)`
    |
-LL -     assert_eq!(true, b!());
-LL +     assert!(b!());
+LL |         true
+...
+LL |
+LL ~     assert!(b!());
    |
 
 error: used `debug_assert_eq!` with a literal bool