Auto merge of #10160 - llogiq:default-trim-paths, r=dswij

trim paths in `default_trait_access`/`clone_on_copy` suggestions

This should help making the suggestions more palatable. Similar to #10153.

---

changelog: trim paths in [`default_trait_access`]/[`clone_on_copy`] suggestions

Author: bors

clippy_lints/src/default.rs

@@ -11,6 +11,7 @@ use rustc_hir::def::Res;
 use rustc_hir::{Block, Expr, ExprKind, PatKind, QPath, Stmt, StmtKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty;
+use rustc_middle::ty::print::with_forced_trimmed_paths;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::symbol::{Ident, Symbol};
 use rustc_span::Span;
@@ -98,9 +99,7 @@ impl<'tcx> LateLintPass<'tcx> for Default {
             if let ty::Adt(def, ..) = expr_ty.kind();
             if !is_from_proc_macro(cx, expr);
             then {
-                // TODO: Work out a way to put "whatever the imported way of referencing
-                // this type in this file" rather than a fully-qualified type.
-                let replacement = format!("{}::default()", cx.tcx.def_path_str(def.did()));
+                let replacement = with_forced_trimmed_paths!(format!("{}::default()", cx.tcx.def_path_str(def.did())));
                 span_lint_and_sugg(
                     cx,
                     DEFAULT_TRAIT_ACCESS,

clippy_lints/src/methods/clone_on_copy.rs

@@ -6,7 +6,7 @@ use clippy_utils::ty::is_copy;
 use rustc_errors::Applicability;
 use rustc_hir::{BindingAnnotation, ByRef, Expr, ExprKind, MatchSource, Node, PatKind, QPath};
 use rustc_lint::LateContext;
-use rustc_middle::ty::{self, adjustment::Adjust};
+use rustc_middle::ty::{self, adjustment::Adjust, print::with_forced_trimmed_paths};
 use rustc_span::symbol::{sym, Symbol};
 
 use super::CLONE_DOUBLE_REF;
@@ -47,10 +47,10 @@ pub(super) fn check(
                 cx,
                 CLONE_DOUBLE_REF,
                 expr.span,
-                &format!(
+                &with_forced_trimmed_paths!(format!(
                     "using `clone` on a double-reference; \
                     this will copy the reference of type `{ty}` instead of cloning the inner type"
-                ),
+                )),
                 |diag| {
                     if let Some(snip) = sugg::Sugg::hir_opt(cx, arg) {
                         let mut ty = innermost;
@@ -61,11 +61,11 @@ pub(super) fn check(
                         }
                         let refs = "&".repeat(n + 1);
                         let derefs = "*".repeat(n);
-                        let explicit = format!("<{refs}{ty}>::clone({snip})");
+                        let explicit = with_forced_trimmed_paths!(format!("<{refs}{ty}>::clone({snip})"));
                         diag.span_suggestion(
                             expr.span,
                             "try dereferencing it",
-                            format!("{refs}({derefs}{}).clone()", snip.deref()),
+                            with_forced_trimmed_paths!(format!("{refs}({derefs}{}).clone()", snip.deref())),
                             Applicability::MaybeIncorrect,
                         );
                         diag.span_suggestion(
@@ -129,7 +129,9 @@ pub(super) fn check(
             cx,
             CLONE_ON_COPY,
             expr.span,
-            &format!("using `clone` on type `{ty}` which implements the `Copy` trait"),
+            &with_forced_trimmed_paths!(format!(
+                "using `clone` on type `{ty}` which implements the `Copy` trait"
+            )),
             help,
             sugg,
             app,

tests/ui/clone_on_copy.stderr

@@ -48,7 +48,7 @@ error: using `clone` on type `i32` which implements the `Copy` trait
 LL |     vec.push(42.clone());
    |              ^^^^^^^^^^ help: try removing the `clone` call: `42`
 
-error: using `clone` on type `std::option::Option<i32>` which implements the `Copy` trait
+error: using `clone` on type `Option<i32>` which implements the `Copy` trait
   --> $DIR/clone_on_copy.rs:77:17
    |
 LL |     let value = opt.clone()?; // operator precedence needed (*opt)?

tests/ui/default_trait_access.fixed

@@ -12,17 +12,17 @@ use std::default::Default as D2;
 use std::string;
 
 fn main() {
-    let s1: String = std::string::String::default();
+    let s1: String = String::default();
 
     let s2 = String::default();
 
-    let s3: String = std::string::String::default();
+    let s3: String = String::default();
 
-    let s4: String = std::string::String::default();
+    let s4: String = String::default();
 
     let s5 = string::String::default();
 
-    let s6: String = std::string::String::default();
+    let s6: String = String::default();
 
     let s7 = std::string::String::default();
 

tests/ui/default_trait_access.stderr

@@ -1,32 +1,32 @@
-error: calling `std::string::String::default()` is more clear than this expression
+error: calling `String::default()` is more clear than this expression
   --> $DIR/default_trait_access.rs:15:22
    |
 LL |     let s1: String = Default::default();
-   |                      ^^^^^^^^^^^^^^^^^^ help: try: `std::string::String::default()`
+   |                      ^^^^^^^^^^^^^^^^^^ help: try: `String::default()`
    |
 note: the lint level is defined here
   --> $DIR/default_trait_access.rs:3:9
    |
 LL | #![deny(clippy::default_trait_access)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: calling `std::string::String::default()` is more clear than this expression
+error: calling `String::default()` is more clear than this expression
   --> $DIR/default_trait_access.rs:19:22
    |
 LL |     let s3: String = D2::default();
-   |                      ^^^^^^^^^^^^^ help: try: `std::string::String::default()`
+   |                      ^^^^^^^^^^^^^ help: try: `String::default()`
 
-error: calling `std::string::String::default()` is more clear than this expression
+error: calling `String::default()` is more clear than this expression
   --> $DIR/default_trait_access.rs:21:22
    |
 LL |     let s4: String = std::default::Default::default();
-   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `std::string::String::default()`
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `String::default()`
 
-error: calling `std::string::String::default()` is more clear than this expression
+error: calling `String::default()` is more clear than this expression
   --> $DIR/default_trait_access.rs:25:22
    |
 LL |     let s6: String = default::Default::default();
-   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `std::string::String::default()`
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `String::default()`
 
 error: calling `GenericDerivedDefault::default()` is more clear than this expression
   --> $DIR/default_trait_access.rs:35:46

tests/ui/unnecessary_clone.stderr

@@ -38,13 +38,13 @@ LL |     t.clone();
    |
    = note: `-D clippy::clone-on-copy` implied by `-D warnings`
 
-error: using `clone` on type `std::option::Option<T>` which implements the `Copy` trait
+error: using `clone` on type `Option<T>` which implements the `Copy` trait
   --> $DIR/unnecessary_clone.rs:42:5
    |
 LL |     Some(t).clone();
    |     ^^^^^^^^^^^^^^^ help: try removing the `clone` call: `Some(t)`
 
-error: using `clone` on a double-reference; this will copy the reference of type `&std::vec::Vec<i32>` instead of cloning the inner type
+error: using `clone` on a double-reference; this will copy the reference of type `&Vec<i32>` instead of cloning the inner type
   --> $DIR/unnecessary_clone.rs:48:22
    |
 LL |     let z: &Vec<_> = y.clone();
@@ -57,10 +57,10 @@ LL |     let z: &Vec<_> = &(*y).clone();
    |                      ~~~~~~~~~~~~~
 help: or try being explicit if you are sure, that you want to clone a reference
    |
-LL |     let z: &Vec<_> = <&std::vec::Vec<i32>>::clone(y);
-   |                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+LL |     let z: &Vec<_> = <&Vec<i32>>::clone(y);
+   |                      ~~~~~~~~~~~~~~~~~~~~~
 
-error: using `clone` on type `many_derefs::E` which implements the `Copy` trait
+error: using `clone` on type `E` which implements the `Copy` trait
   --> $DIR/unnecessary_clone.rs:84:20
    |
 LL |         let _: E = a.clone();