Fix lint errors

Author: Kobzol

clippy_lints/src/assigning_clones.rs

@@ -61,16 +61,14 @@ impl<'tcx> LateLintPass<'tcx> for AssigningClones {
         };
 
         if is_ok_to_suggest(cx, lhs, &call) {
-            suggest(cx, assign_expr, lhs, call);
+            suggest(cx, assign_expr, lhs, &call);
         }
     }
 }
 
 // Try to resolve the call to `Clone::clone` or `ToOwned::to_owned`.
 fn extract_call<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Option<CallCandidate<'tcx>> {
-    let Some(fn_def_id) = clippy_utils::fn_def_id(cx, expr) else {
-        return None;
-    };
+    let fn_def_id = clippy_utils::fn_def_id(cx, expr)?;
 
     // Fast paths to only check method calls without arguments or function calls with a single argument
     let (target, kind, resolved_method) = match expr.kind {
@@ -182,7 +180,7 @@ fn suggest<'tcx>(
     cx: &LateContext<'tcx>,
     assign_expr: &hir::Expr<'tcx>,
     lhs: &hir::Expr<'tcx>,
-    call: CallCandidate<'tcx>,
+    call: &CallCandidate<'tcx>,
 ) {
     span_lint_and_then(cx, ASSIGNING_CLONES, assign_expr.span, call.message(), |diag| {
         let mut applicability = Applicability::MachineApplicable;

clippy_utils/src/sugg.rs

@@ -994,7 +994,7 @@ impl<'tcx> Delegate<'tcx> for DerefDelegate<'_, 'tcx> {
                         // no adjustment needed here, as field projections are handled by the compiler
                         ProjectionKind::Field(..) => match cmt.place.ty_before_projection(i).kind() {
                             ty::Adt(..) | ty::Tuple(_) => {
-                                replacement_str = ident_str_with_proj.clone();
+                                replacement_str.clone_from(&ident_str_with_proj);
                                 projections_handled = true;
                             },
                             _ => (),

tests/missing-test-files.rs

@@ -54,7 +54,7 @@ fn explore_directory(dir: &Path) -> Vec<String> {
             let file_prefix = path.file_prefix().unwrap().to_str().unwrap().to_string();
             if let Some(ext) = path.extension() {
                 match ext.to_str().unwrap() {
-                    "rs" | "toml" => current_file = file_prefix.clone(),
+                    "rs" | "toml" => current_file.clone_from(&file_prefix),
                     "stderr" | "stdout" => {
                         if file_prefix != current_file {
                             missing_files.push(path.to_str().unwrap().to_string());