diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs
index 1394f4083d0b9..e9f596e3a5ba4 100644
--- a/compiler/rustc_resolve/src/late/diagnostics.rs
+++ b/compiler/rustc_resolve/src/late/diagnostics.rs
@@ -2379,9 +2379,7 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
                     suggs.push(match snippet.as_deref() {
                         Some("&") => Some("&'a ".to_string()),
                         Some("'_") => Some("'a".to_string()),
-                        Some("") => {
-                            Some(std::iter::repeat("'a, ").take(count).collect::<Vec<_>>().join(""))
-                        }
+                        Some("") => Some(std::iter::repeat("'a, ").take(count).collect::<String>()),
                         Some("<") => {
                             Some(std::iter::repeat("'a").take(count).collect::<Vec<_>>().join(", "))
                         }