1 files changed, 38 insertions, 0 deletions
diff --git a/tests/ui/string_to_string_in_map.stderr b/tests/ui/string_to_string_in_map.stderr
new file mode 100644
index 00000000000..35aeed656ee
--- /dev/null
+++ b/tests/ui/string_to_string_in_map.stderr
@@ -0,0 +1,38 @@
+error: `to_string()` called on a `String`
+  --> tests/ui/string_to_string_in_map.rs:8:23
+   |
+LL |     let _ = variable2.map(String::to_string);
+   |                       ^^^^^^^^^^^^^^^^^^^^^^ help: try: `cloned()`
+   |
+note: the lint level is defined here
+  --> tests/ui/string_to_string_in_map.rs:1:9
+   |
+LL | #![deny(clippy::string_to_string)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: `to_string()` called on a `String`
+  --> tests/ui/string_to_string_in_map.rs:10:23
+   |
+LL |     let _ = variable2.map(|x| x.to_string());
+   |                       ^^^^^^^^^^^^^^^^^^^^^^ help: try: `cloned()`
+
+error: `to_string()` called on a `String`
+  --> tests/ui/string_to_string_in_map.rs:13:23
+   |
+LL |     let _ = variable2.map(|x| { x.to_string() });
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `cloned()`
+
+error: `to_string()` called on a `String`
+  --> tests/ui/string_to_string_in_map.rs:16:40
+   |
+LL |     let _ = vec![String::new()].iter().map(String::to_string).collect::<Vec<_>>();
+   |                                        ^^^^^^^^^^^^^^^^^^^^^^ help: try: `cloned()`
+
+error: `to_string()` called on a `String`
+  --> tests/ui/string_to_string_in_map.rs:18:40
+   |
+LL |     let _ = vec![String::new()].iter().map(|x| x.to_string()).collect::<Vec<_>>();
+   |                                        ^^^^^^^^^^^^^^^^^^^^^^ help: try: `cloned()`
+
+error: aborting due to 5 previous errors
+