Auto merge of #68376 - Centril:move-ref-patterns, r=matthewjasper

Initial implementation of `#![feature(move_ref_pattern)]`

Following up on #45600, under the gate `#![feature(move_ref_pattern)]`, `(ref x, mut y)` is allowed subject to restrictions necessary for soundness. The match checking implementation and tests for `#![feature(bindings_after_at)]` is also adjusted as necessary.

Closes #45600.
Tracking issue: #68354.

r? @matthewjasper

1 files changed, 15 insertions, 1 deletions

diff --git a/src/librustc_errors/diagnostic_builder.rs b/src/librustc_errors/diagnostic_builder.rs
index 3c217c1d643..82bbae18a9c 100644
--- a/src/librustc_errors/diagnostic_builder.rs
+++ b/src/librustc_errors/diagnostic_builder.rs
@@ -186,11 +186,25 @@ impl<'a> DiagnosticBuilder<'a> {
     /// all, and you just supplied a `Span` to create the diagnostic,
     /// then the snippet will just include that `Span`, which is
     /// called the primary span.
-    pub fn span_label<T: Into<String>>(&mut self, span: Span, label: T) -> &mut Self {
+    pub fn span_label(&mut self, span: Span, label: impl Into<String>) -> &mut Self {
         self.0.diagnostic.span_label(span, label);
         self
     }
 
+    /// Labels all the given spans with the provided label.
+    /// See `span_label` for more information.
+    pub fn span_labels(
+        &mut self,
+        spans: impl IntoIterator<Item = Span>,
+        label: impl AsRef<str>,
+    ) -> &mut Self {
+        let label = label.as_ref();
+        for span in spans {
+            self.0.diagnostic.span_label(span, label);
+        }
+        self
+    }
+
     forward!(pub fn note_expected_found(
         &mut self,
         expected_label: &dyn fmt::Display,