diff --git a/src/libcore/ops/function.rs b/src/libcore/ops/function.rs
index 22a738d0bc1c0..4f08aa451875f 100644
--- a/src/libcore/ops/function.rs
+++ b/src/libcore/ops/function.rs
@@ -59,7 +59,7 @@
 #[rustc_on_unimplemented(
     on(
         Args = "()",
-        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}"
+        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}`"
     ),
     message = "expected a `{Fn}<{Args}>` closure, found `{Self}`",
     label = "expected an `Fn<{Args}>` closure, found `{Self}`"
@@ -141,7 +141,7 @@ pub trait Fn<Args>: FnMut<Args> {
 #[rustc_on_unimplemented(
     on(
         Args = "()",
-        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}"
+        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}`"
     ),
     message = "expected a `{FnMut}<{Args}>` closure, found `{Self}`",
     label = "expected an `FnMut<{Args}>` closure, found `{Self}`"
@@ -215,7 +215,7 @@ pub trait FnMut<Args>: FnOnce<Args> {
 #[rustc_on_unimplemented(
     on(
         Args = "()",
-        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}"
+        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}`"
     ),
     message = "expected a `{FnOnce}<{Args}>` closure, found `{Self}`",
     label = "expected an `FnOnce<{Args}>` closure, found `{Self}`"
diff --git a/src/test/ui/closure-expected.stderr b/src/test/ui/closure-expected.stderr
index ae4f4d69b5ef5..687dd97ca6cef 100644
--- a/src/test/ui/closure-expected.stderr
+++ b/src/test/ui/closure-expected.stderr
@@ -5,7 +5,7 @@ LL |     let y = x.or_else(4);
    |                       ^ expected an `FnOnce<()>` closure, found `{integer}`
    |
    = help: the trait `std::ops::FnOnce<()>` is not implemented for `{integer}`
-   = note: wrap the `{integer}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `{integer}` in a closure with no arguments: `|| { /* code */ }`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/extern/extern-wrong-value-type.stderr b/src/test/ui/extern/extern-wrong-value-type.stderr
index 64f01b47792c7..2cb15f84f6973 100644
--- a/src/test/ui/extern/extern-wrong-value-type.stderr
+++ b/src/test/ui/extern/extern-wrong-value-type.stderr
@@ -8,7 +8,7 @@ LL |     is_fn(f);
    |           ^ expected an `Fn<()>` closure, found `extern "C" fn() {f}`
    |
    = help: the trait `std::ops::Fn<()>` is not implemented for `extern "C" fn() {f}`
-   = note: wrap the `extern "C" fn() {f}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `extern "C" fn() {f}` in a closure with no arguments: `|| { /* code */ }`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr b/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr
index 2fab7ffb66050..2fe266b8018eb 100644
--- a/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr
+++ b/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr
@@ -16,7 +16,7 @@ LL |     type F<'a>: Fn() -> u32;
 LL |     type F<'a> = Self;
    |     ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T`
    |
-   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }`
 help: consider restricting type parameter `T`
    |
 LL | impl<T: std::ops::Fn<()>> Fun for T {
diff --git a/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr b/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr
index 186e142138be2..e335523778b47 100644
--- a/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr
+++ b/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr
@@ -16,7 +16,7 @@ LL |     type F<'a>: Fn() -> u32;
 LL |     type F<'a> = Self;
    |     ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T`
    |
-   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }`
 help: consider restricting type parameter `T`
    |
 LL | impl<T: std::ops::Fn<()>> Fun for T {
diff --git a/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr b/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr
index d16bdcbbb6b00..d7a5bb0ebe543 100644
--- a/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr
+++ b/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr
@@ -16,7 +16,7 @@ LL |     type F<'a>: Fn() -> u32;
 LL |     type F<'a> = Self;
    |     ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T`
    |
-   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }`
 help: consider restricting type parameter `T`
    |
 LL | impl<T: std::ops::Fn<()>> Fun for T {
diff --git a/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr b/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr
index 72c42917c83c9..0670625aa2f1b 100644
--- a/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr
+++ b/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr
@@ -16,7 +16,7 @@ LL |     type F<'a>: Fn() -> u32;
 LL |     type F<'a> = Self;
    |     ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T`
    |
-   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `T` in a closure with no arguments: `|| { /* code */ }`
 help: consider restricting type parameter `T`
    |
 LL | impl<T: std::ops::Fn<()>> Fun for T {
diff --git a/src/test/ui/issues/issue-22034.stderr b/src/test/ui/issues/issue-22034.stderr
index 19fb080154a4a..132880aab11e3 100644
--- a/src/test/ui/issues/issue-22034.stderr
+++ b/src/test/ui/issues/issue-22034.stderr
@@ -5,7 +5,7 @@ LL |         &mut *(ptr as *mut dyn Fn())
    |                ^^^ expected an `Fn<()>` closure, found `()`
    |
    = help: the trait `std::ops::Fn<()>` is not implemented for `()`
-   = note: wrap the `()` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `()` in a closure with no arguments: `|| { /* code */ }`
    = note: required for the cast to the object type `dyn std::ops::Fn()`
 
 error: aborting due to previous error
diff --git a/src/test/ui/rfcs/rfc-2396-target_feature-11/fn-traits.stderr b/src/test/ui/rfcs/rfc-2396-target_feature-11/fn-traits.stderr
index 448077b439e80..f9b4eed0497c4 100644
--- a/src/test/ui/rfcs/rfc-2396-target_feature-11/fn-traits.stderr
+++ b/src/test/ui/rfcs/rfc-2396-target_feature-11/fn-traits.stderr
@@ -8,7 +8,7 @@ LL |     call(foo);
    |          ^^^ expected an `Fn<()>` closure, found `fn() {foo}`
    |
    = help: the trait `std::ops::Fn<()>` is not implemented for `fn() {foo}`
-   = note: wrap the `fn() {foo}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 
 error[E0277]: expected a `std::ops::FnMut<()>` closure, found `fn() {foo}`
@@ -21,7 +21,7 @@ LL |     call_mut(foo);
    |              ^^^ expected an `FnMut<()>` closure, found `fn() {foo}`
    |
    = help: the trait `std::ops::FnMut<()>` is not implemented for `fn() {foo}`
-   = note: wrap the `fn() {foo}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 
 error[E0277]: expected a `std::ops::FnOnce<()>` closure, found `fn() {foo}`
@@ -34,7 +34,7 @@ LL |     call_once(foo);
    |               ^^^ expected an `FnOnce<()>` closure, found `fn() {foo}`
    |
    = help: the trait `std::ops::FnOnce<()>` is not implemented for `fn() {foo}`
-   = note: wrap the `fn() {foo}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 
 error[E0277]: expected a `std::ops::Fn<()>` closure, found `unsafe fn() {foo_unsafe}`
@@ -47,7 +47,7 @@ LL |     call(foo_unsafe);
    |          ^^^^^^^^^^ expected an `Fn<()>` closure, found `unsafe fn() {foo_unsafe}`
    |
    = help: the trait `std::ops::Fn<()>` is not implemented for `unsafe fn() {foo_unsafe}`
-   = note: wrap the `unsafe fn() {foo_unsafe}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `unsafe fn() {foo_unsafe}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 
 error[E0277]: expected a `std::ops::FnMut<()>` closure, found `unsafe fn() {foo_unsafe}`
@@ -60,7 +60,7 @@ LL |     call_mut(foo_unsafe);
    |              ^^^^^^^^^^ expected an `FnMut<()>` closure, found `unsafe fn() {foo_unsafe}`
    |
    = help: the trait `std::ops::FnMut<()>` is not implemented for `unsafe fn() {foo_unsafe}`
-   = note: wrap the `unsafe fn() {foo_unsafe}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `unsafe fn() {foo_unsafe}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 
 error[E0277]: expected a `std::ops::FnOnce<()>` closure, found `unsafe fn() {foo_unsafe}`
@@ -73,7 +73,7 @@ LL |     call_once(foo_unsafe);
    |               ^^^^^^^^^^ expected an `FnOnce<()>` closure, found `unsafe fn() {foo_unsafe}`
    |
    = help: the trait `std::ops::FnOnce<()>` is not implemented for `unsafe fn() {foo_unsafe}`
-   = note: wrap the `unsafe fn() {foo_unsafe}` in a closure with no arguments: `|| { /* code */ }
+   = note: wrap the `unsafe fn() {foo_unsafe}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 
 error: aborting due to 6 previous errors