Auto merge of #123413 - petrochenkov:delegmulti2, r=fmease

delegation: Implement list delegation

```rust
reuse prefix::{a, b, c};
```

Using design described in https://github.com/rust-lang/rfcs/pull/3530#issuecomment-2020869823 (the lists are desugared at macro expansion time).
List delegations are expanded eagerly when encountered, similarly to `#[cfg]`s, and not enqueued for later resolution/expansion like regular macros or glob delegation (https://github.com/rust-lang/rust/pull/124135).

Part of https://github.com/rust-lang/rust/issues/118212.

2 files changed, 3 insertions, 3 deletions

diff --git a/src/tools/rustfmt/src/items.rs b/src/tools/rustfmt/src/items.rs
index e196d1817f3..90e9e58ef9c 100644
--- a/src/tools/rustfmt/src/items.rs
+++ b/src/tools/rustfmt/src/items.rs
@@ -739,8 +739,8 @@ impl<'a> FmtVisitor<'a> {
                 (_, Const(..)) => Ordering::Greater,
                 (MacCall(..), _) => Ordering::Less,
                 (_, MacCall(..)) => Ordering::Greater,
-                (Delegation(..), _) => Ordering::Less,
-                (_, Delegation(..)) => Ordering::Greater,
+                (Delegation(..), _) | (DelegationMac(..), _) => Ordering::Less,
+                (_, Delegation(..)) | (_, DelegationMac(..)) => Ordering::Greater,
             });
             let mut prev_kind = None;
             for (buf, item) in buffer {
diff --git a/src/tools/rustfmt/src/visitor.rs b/src/tools/rustfmt/src/visitor.rs
index 6209b37004b..e1c7dc35087 100644
--- a/src/tools/rustfmt/src/visitor.rs
+++ b/src/tools/rustfmt/src/visitor.rs
@@ -586,7 +586,7 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                     );
                     self.push_rewrite(item.span, rewrite);
                 }
-                ast::ItemKind::Delegation(..) => {
+                ast::ItemKind::Delegation(..) | ast::ItemKind::DelegationMac(..) => {
                     // TODO: rewrite delegation items once syntax is established.
                     // For now, leave the contents of the Span unformatted.
                     self.push_rewrite(item.span, None)