Add error message to manual_inspect lint

Author: flip1995

clippy_lints/src/methods/manual_inspect.rs

@@ -167,14 +167,12 @@ pub(crate) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, arg: &Expr<'_>, name:
             } else {
                 edits.extend(addr_of_edits);
             }
-            edits.push((
-                name_span,
-                String::from(match name {
-                    "map" => "inspect",
-                    "map_err" => "inspect_err",
-                    _ => return,
-                }),
-            ));
+            let edit = match name {
+                "map" => "inspect",
+                "map_err" => "inspect_err",
+                _ => return,
+            };
+            edits.push((name_span, edit.to_string()));
             edits.push((
                 final_expr
                     .span
@@ -187,9 +185,15 @@ pub(crate) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, arg: &Expr<'_>, name:
             } else {
                 Applicability::MachineApplicable
             };
-            span_lint_and_then(cx, MANUAL_INSPECT, name_span, "", |diag| {
-                diag.multipart_suggestion("try", edits, app);
-            });
+            span_lint_and_then(
+                cx,
+                MANUAL_INSPECT,
+                name_span,
+                format!("using `{name}` over `{edit}`"),
+                |diag| {
+                    diag.multipart_suggestion("try", edits, app);
+                },
+            );
         }
     }
 }

tests/ui/manual_inspect.stderr

@@ -1,4 +1,4 @@
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:5:21
    |
 LL |     let _ = Some(0).map(|x| {
@@ -12,7 +12,7 @@ LL ~     let _ = Some(0).inspect(|&x| {
 LL ~         println!("{}", x);
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:10:21
    |
 LL |     let _ = Some(0).map(|x| {
@@ -24,7 +24,7 @@ LL ~     let _ = Some(0).inspect(|&x| {
 LL ~         println!("{x}");
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:15:21
    |
 LL |     let _ = Some(0).map(|x| {
@@ -36,7 +36,7 @@ LL ~     let _ = Some(0).inspect(|&x| {
 LL ~         println!("{}", x * 5 + 1);
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:20:21
    |
 LL |     let _ = Some(0).map(|x| {
@@ -50,7 +50,7 @@ LL |             panic!();
 LL ~         }
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:27:21
    |
 LL |     let _ = Some(0).map(|x| {
@@ -65,7 +65,7 @@ LL |             panic!();
 LL ~         }
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:78:41
    |
 LL |     let _ = Some((String::new(), 0u32)).map(|x| {
@@ -80,7 +80,7 @@ LL |             panic!();
 LL ~         }
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:104:33
    |
 LL |     let _ = Some(String::new()).map(|x| {
@@ -98,7 +98,7 @@ LL |         }
 LL ~         println!("test");
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:115:21
    |
 LL |     let _ = Some(0).map(|x| {
@@ -113,7 +113,7 @@ LL |             panic!();
 LL ~         }
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:130:46
    |
 LL |         let _ = Some(Cell2(Cell::new(0u32))).map(|x| {
@@ -125,7 +125,7 @@ LL ~         let _ = Some(Cell2(Cell::new(0u32))).inspect(|x| {
 LL ~             x.0.set(1);
    |
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:146:34
    |
 LL |     let _: Result<_, ()> = Ok(0).map(|x| {
@@ -137,7 +137,7 @@ LL ~     let _: Result<_, ()> = Ok(0).inspect(|&x| {
 LL ~         println!("{}", x);
    |
 
-error: 
+error: using `map_err` over `inspect_err`
   --> tests/ui/manual_inspect.rs:151:35
    |
 LL |     let _: Result<(), _> = Err(0).map_err(|x| {
@@ -166,7 +166,7 @@ LL | |         .count();
    = note: `-D clippy::suspicious-map` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::suspicious_map)]`
 
-error: 
+error: using `map` over `inspect`
   --> tests/ui/manual_inspect.rs:158:10
    |
 LL |         .map(|x| {