1 files changed, 5 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/format_push_string.rs b/src/tools/clippy/tests/ui/format_push_string.rs
index 89423ffe1..735ae3393 100644
--- a/src/tools/clippy/tests/ui/format_push_string.rs
+++ b/src/tools/clippy/tests/ui/format_push_string.rs
@@ -3,7 +3,9 @@
 fn main() {
     let mut string = String::new();
     string += &format!("{:?}", 1234);
+    //~^ ERROR: `format!(..)` appended to existing `String`
     string.push_str(&format!("{:?}", 5678));
+    //~^ ERROR: `format!(..)` appended to existing `String`
 }
 
 mod issue9493 {
@@ -11,6 +13,7 @@ mod issue9493 {
         let mut hex = String::with_capacity(vector.len() * 2);
         for byte in vector {
             hex += &(if upper {
+                //~^ ERROR: `format!(..)` appended to existing `String`
                 format!("{byte:02X}")
             } else {
                 format!("{byte:02x}")
@@ -23,12 +26,14 @@ mod issue9493 {
         let mut s = String::new();
         // if let
         s += &(if let Some(_a) = Some(1234) {
+            //~^ ERROR: `format!(..)` appended to existing `String`
             format!("{}", 1234)
         } else {
             format!("{}", 1234)
         });
         // match
         s += &(match Some(1234) {
+            //~^ ERROR: `format!(..)` appended to existing `String`
             Some(_) => format!("{}", 1234),
             None => format!("{}", 1234),
         });