-use crate::utils::{match_def_path, match_trait_method, paths, qpath_res, span_lint};
+use clippy_utils::diagnostics::span_lint;
+use clippy_utils::{is_diag_trait_item, match_def_path, path_to_local_id, paths};
use if_chain::if_chain;
-use rustc_hir::def::Res;
-use rustc_hir::{Expr, ExprKind, HirId, ImplItem, ImplItemKind, Item, ItemKind, Impl};
+use rustc_hir::{Expr, ExprKind, HirId, Impl, ImplItem, ImplItemKind, Item, ItemKind};
use rustc_lint::{LateContext, LateLintPass};
use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::symbol::sym;
declare_clippy_lint! {
/// **What it does:** Checks for uses of `to_string()` in `Display` traits.
fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
if_chain! {
- if let ExprKind::MethodCall(ref path, _, args, _) = expr.kind;
- if path.ident.name == sym!(to_string);
- if match_trait_method(cx, expr, &paths::TO_STRING);
if self.in_display_impl;
- if let ExprKind::Path(ref qpath) = args[0].kind;
- if let Res::Local(hir_id) = qpath_res(cx, qpath, args[0].hir_id);
if let Some(self_hir_id) = self.self_hir_id;
- if hir_id == self_hir_id;
+ if let ExprKind::MethodCall(path, _, args, _) = expr.kind;
+ if path.ident.name == sym!(to_string);
+ if let Some(expr_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
+ if is_diag_trait_item(cx, expr_def_id, sym::ToString);
+ if path_to_local_id(&args[0], self_hir_id);
then {
span_lint(
cx,