suggestion for rest_pat_in_fully_bound_structs (#15648)

changelog: [`rest_pat_in_fully_bound_structs`]: add suggestion

Author: samueltardieu

clippy_lints/src/matches/rest_pat_in_fully_bound_struct.rs

@@ -7,22 +7,26 @@ use super::REST_PAT_IN_FULLY_BOUND_STRUCTS;
 
 pub(crate) fn check(cx: &LateContext<'_>, pat: &Pat<'_>) {
     if !pat.span.from_expansion()
-        && let PatKind::Struct(QPath::Resolved(_, path), fields, Some(_)) = pat.kind
+        && let PatKind::Struct(QPath::Resolved(_, path), fields, Some(dotdot)) = pat.kind
         && let Some(def_id) = path.res.opt_def_id()
         && let ty = cx.tcx.type_of(def_id).instantiate_identity()
         && let ty::Adt(def, _) = ty.kind()
         && (def.is_struct() || def.is_union())
         && fields.len() == def.non_enum_variant().fields.len()
         && !def.non_enum_variant().is_field_list_non_exhaustive()
     {
-        #[expect(clippy::collapsible_span_lint_calls, reason = "rust-clippy#7797")]
         span_lint_and_then(
             cx,
             REST_PAT_IN_FULLY_BOUND_STRUCTS,
             pat.span,
             "unnecessary use of `..` pattern in struct binding. All fields were already bound",
             |diag| {
-                diag.help("consider removing `..` from this binding");
+                diag.span_suggestion_verbose(
+                    dotdot,
+                    "consider removing `..` from this binding",
+                    "",
+                    rustc_errors::Applicability::MachineApplicable,
+                );
             },
         );
     }

tests/ui/rest_pat_in_fully_bound_structs.fixed

@@ -0,0 +1,61 @@
+#![warn(clippy::rest_pat_in_fully_bound_structs)]
+#![allow(clippy::struct_field_names)]
+
+struct A {
+    a: i32,
+    b: i64,
+    c: &'static str,
+}
+
+macro_rules! foo {
+    ($param:expr) => {
+        match $param {
+            A { a: 0, b: 0, c: "", .. } => {},
+            _ => {},
+        }
+    };
+}
+
+fn main() {
+    let a_struct = A { a: 5, b: 42, c: "A" };
+
+    match a_struct {
+        A { a: 5, b: 42, c: "",  } => {}, // Lint
+        //~^ rest_pat_in_fully_bound_structs
+        A { a: 0, b: 0, c: "",  } => {}, // Lint
+        //~^ rest_pat_in_fully_bound_structs
+        _ => {},
+    }
+
+    match a_struct {
+        A { a: 5, b: 42, .. } => {},
+        A { a: 0, b: 0, c: "",  } => {}, // Lint
+        //~^ rest_pat_in_fully_bound_structs
+        _ => {},
+    }
+
+    // No lint
+    match a_struct {
+        A { a: 5, .. } => {},
+        A { a: 0, b: 0, .. } => {},
+        _ => {},
+    }
+
+    // No lint
+    foo!(a_struct);
+
+    #[non_exhaustive]
+    struct B {
+        a: u32,
+        b: u32,
+        c: u64,
+    }
+
+    let b_struct = B { a: 5, b: 42, c: 342 };
+
+    match b_struct {
+        B { a: 5, b: 42, .. } => {},
+        B { a: 0, b: 0, c: 128, .. } => {}, // No Lint
+        _ => {},
+    }
+}

tests/ui/rest_pat_in_fully_bound_structs.stderr

@@ -4,25 +4,37 @@ error: unnecessary use of `..` pattern in struct binding. All fields were alread
 LL |         A { a: 5, b: 42, c: "", .. } => {}, // Lint
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: consider removing `..` from this binding
    = note: `-D clippy::rest-pat-in-fully-bound-structs` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::rest_pat_in_fully_bound_structs)]`
+help: consider removing `..` from this binding
+   |
+LL -         A { a: 5, b: 42, c: "", .. } => {}, // Lint
+LL +         A { a: 5, b: 42, c: "",  } => {}, // Lint
+   |
 
 error: unnecessary use of `..` pattern in struct binding. All fields were already bound
   --> tests/ui/rest_pat_in_fully_bound_structs.rs:25:9
    |
 LL |         A { a: 0, b: 0, c: "", .. } => {}, // Lint
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: consider removing `..` from this binding
+help: consider removing `..` from this binding
+   |
+LL -         A { a: 0, b: 0, c: "", .. } => {}, // Lint
+LL +         A { a: 0, b: 0, c: "",  } => {}, // Lint
+   |
 
 error: unnecessary use of `..` pattern in struct binding. All fields were already bound
   --> tests/ui/rest_pat_in_fully_bound_structs.rs:32:9
    |
 LL |         A { a: 0, b: 0, c: "", .. } => {}, // Lint
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: consider removing `..` from this binding
+help: consider removing `..` from this binding
+   |
+LL -         A { a: 0, b: 0, c: "", .. } => {}, // Lint
+LL +         A { a: 0, b: 0, c: "",  } => {}, // Lint
+   |
 
 error: aborting due to 3 previous errors