Auto merge of #84373 - cjgillot:resolve-span, r=michaelwoerister,petrochenkov

[rust.git] / clippy_lints / src / useless_conversion.rs

diff --git a/clippy_lints/src/useless_conversion.rs b/clippy_lints/src/useless_conversion.rs
index 7edb280be73eabb6ff0eef97fb3160414d7525e9..2861b43291901dfe493443d2e576d6dbd7ffea38 100644 (file)
--- a/clippy_lints/src/useless_conversion.rs
+++ b/clippy_lints/src/useless_conversion.rs
@@ -1,26 +1,25 @@
 use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_sugg};
 use clippy_utils::source::{snippet, snippet_with_macro_callsite};
 use clippy_utils::sugg::Sugg;
-use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{get_parent_expr, match_def_path, match_trait_method, paths};
+use clippy_utils::ty::{is_type_diagnostic_item, same_type_and_consts};
+use clippy_utils::{get_parent_expr, is_trait_method, match_def_path, paths};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::{Expr, ExprKind, HirId, MatchSource};
 use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty::{self, TyS};
+use rustc_middle::ty;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::sym;
 
 declare_clippy_lint! {
-    /// **What it does:** Checks for `Into`, `TryInto`, `From`, `TryFrom`, or `IntoIter` calls
+    /// ### What it does
+    /// Checks for `Into`, `TryInto`, `From`, `TryFrom`, or `IntoIter` calls
     /// which uselessly convert to the same type.
     ///
-    /// **Why is this bad?** Redundant code.
-    ///
-    /// **Known problems:** None.
-    ///
-    /// **Example:**
+    /// ### Why is this bad?
+    /// Redundant code.
     ///
+    /// ### Example
     /// ```rust
     /// // Bad
     /// // format!() returns a `String`
@@ -64,10 +63,10 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
             },
 
             ExprKind::MethodCall(name, .., args, _) => {
-                if match_trait_method(cx, e, &paths::INTO) && &*name.ident.as_str() == "into" {
+                if is_trait_method(cx, e, sym::into_trait) && &*name.ident.as_str() == "into" {
                     let a = cx.typeck_results().expr_ty(e);
                     let b = cx.typeck_results().expr_ty(&args[0]);
-                    if TyS::same_type(a, b) {
+                    if same_type_and_consts(a, b) {
                         let sugg = snippet_with_macro_callsite(cx, args[0].span, "<expr>").to_string();
                         span_lint_and_sugg(
                             cx,
@@ -80,7 +79,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
                         );
                     }
                 }
-                if match_trait_method(cx, e, &paths::INTO_ITERATOR) && name.ident.name == sym::into_iter {
+                if is_trait_method(cx, e, sym::IntoIterator) && name.ident.name == sym::into_iter {
                     if let Some(parent_expr) = get_parent_expr(cx, e) {
                         if let ExprKind::MethodCall(parent_name, ..) = parent_expr.kind {
                             if parent_name.ident.name != sym::into_iter {
@@ -90,7 +89,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
                     }
                     let a = cx.typeck_results().expr_ty(e);
                     let b = cx.typeck_results().expr_ty(&args[0]);
-                    if TyS::same_type(a, b) {
+                    if same_type_and_consts(a, b) {
                         let sugg = snippet(cx, args[0].span, "<expr>").into_owned();
                         span_lint_and_sugg(
                             cx,
@@ -104,13 +103,14 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
                     }
                 }
                 if_chain! {
-                    if match_trait_method(cx, e, &paths::TRY_INTO_TRAIT) && &*name.ident.as_str() == "try_into";
+                    if is_trait_method(cx, e, sym::try_into_trait) && name.ident.name == sym::try_into;
                     let a = cx.typeck_results().expr_ty(e);
                     let b = cx.typeck_results().expr_ty(&args[0]);
                     if is_type_diagnostic_item(cx, a, sym::result_type);
                     if let ty::Adt(_, substs) = a.kind();
                     if let Some(a_type) = substs.types().next();
-                    if TyS::same_type(a_type, b);
+                    if same_type_and_consts(a_type, b);
+
                     then {
                         span_lint_and_help(
                             cx,
@@ -137,7 +137,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
                             if is_type_diagnostic_item(cx, a, sym::result_type);
                             if let ty::Adt(_, substs) = a.kind();
                             if let Some(a_type) = substs.types().next();
-                            if TyS::same_type(a_type, b);
+                            if same_type_and_consts(a_type, b);
 
                             then {
                                 let hint = format!("consider removing `{}()`", snippet(cx, path.span, "TryFrom::try_from"));
@@ -154,7 +154,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
 
                         if_chain! {
                             if match_def_path(cx, def_id, &paths::FROM_FROM);
-                            if TyS::same_type(a, b);
+                            if same_type_and_consts(a, b);
 
                             then {
                                 let sugg = Sugg::hir_with_macro_callsite(cx, &args[0], "<expr>").maybe_par();