Remove references to sized for end users

CHANGELOG.md

@@ -899,7 +899,7 @@ All notable changes to this project will be documented in this file.
 [`useless_let_if_seq`]: https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
 [`useless_transmute`]: https://rust-lang.github.io/rust-clippy/master/index.html#useless_transmute
 [`useless_vec`]: https://rust-lang.github.io/rust-clippy/master/index.html#useless_vec
-[`vec_box_sized`]: https://rust-lang.github.io/rust-clippy/master/index.html#vec_box_sized
+[`vec_box`]: https://rust-lang.github.io/rust-clippy/master/index.html#vec_box
 [`verbose_bit_mask`]: https://rust-lang.github.io/rust-clippy/master/index.html#verbose_bit_mask
 [`while_immutable_condition`]: https://rust-lang.github.io/rust-clippy/master/index.html#while_immutable_condition
 [`while_let_loop`]: https://rust-lang.github.io/rust-clippy/master/index.html#while_let_loop

clippy_lints/src/lib.rs

@@ -766,7 +766,7 @@ pub fn register_plugins(reg: &mut rustc_plugin::Registry<'_>, conf: &Conf) {
         types::UNIT_ARG,
         types::UNIT_CMP,
         types::UNNECESSARY_CAST,
-        types::VEC_BOX_SIZED,
+        types::VEC_BOX,
         unicode::ZERO_WIDTH_SPACE,
         unsafe_removed_from_name::UNSAFE_REMOVED_FROM_NAME,
         unused_io_amount::UNUSED_IO_AMOUNT,
@@ -932,7 +932,7 @@ pub fn register_plugins(reg: &mut rustc_plugin::Registry<'_>, conf: &Conf) {
         types::TYPE_COMPLEXITY,
         types::UNIT_ARG,
         types::UNNECESSARY_CAST,
-        types::VEC_BOX_SIZED,
+        types::VEC_BOX,
         unused_label::UNUSED_LABEL,
         zero_div_zero::ZERO_DIVIDED_BY_ZERO,
     ]);

clippy_lints/src/types.rs

@@ -90,7 +90,7 @@ declare_clippy_lint! {
 /// }
 /// ```
 declare_clippy_lint! {
-    pub VEC_BOX_SIZED,
+    pub VEC_BOX,
     complexity,
     "usage of `Vec<Box<T>>` where T: Sized, vector elements are already on the heap"
 }
@@ -175,7 +175,7 @@ declare_clippy_lint! {
 
 impl LintPass for TypePass {
     fn get_lints(&self) -> LintArray {
-        lint_array!(BOX_VEC, VEC_BOX_SIZED, OPTION_OPTION, LINKEDLIST, BORROWED_BOX)
+        lint_array!(BOX_VEC, VEC_BOX, OPTION_OPTION, LINKEDLIST, BORROWED_BOX)
     }
 }
 
@@ -292,13 +292,14 @@ fn check_ty(cx: &LateContext<'_, '_>, ast_ty: &hir::Ty, is_local: bool) {
                         then {
                             span_lint_and_sugg(
                                 cx,
-                                VEC_BOX_SIZED,
+                                VEC_BOX,
                                 ast_ty.span,
-                                "you seem to be trying to use `Vec<Box<T>>`, but T is Sized. `Vec<T>` is already on the heap, `Vec<Box<T>>` makes an extra allocation.",
+                                "`Vec<T>` is already on the heap, the boxing is unnecessary.",
                                 "try",
                                 format!("Vec<{}>", boxed_type),
-                                Applicability::MachineApplicable
+                                Applicability::MaybeIncorrect,
-                            )
+                            );
+                            return; // don't recurse into the type
                         }
                     }
                 } else if match_def_path(cx.tcx, def_id, &paths::OPTION) {

tests/ui/vec_box_sized.stderr

@@ -1,10 +1,10 @@
-error: you seem to be trying to use `Vec<Box<T>>`, but T is Sized. `Vec<T>` is already on the heap, `Vec<Box<T>>` makes an extra allocation.
+error: `Vec<T>` is already on the heap, the boxing is unnecessary.
   --> $DIR/vec_box_sized.rs:10:14
    |
 10 |     sized_type: Vec<Box<SizedStruct>>,
    |                 ^^^^^^^^^^^^^^^^^^^^^ help: try: `Vec<SizedStruct>`
    |
-   = note: `-D clippy::vec-box-sized` implied by `-D warnings`
+   = note: `-D clippy::vec-box` implied by `-D warnings`
 
 error: aborting due to previous error