Use verbose suggestion for ptr::null_mut()

Author: estebank

compiler/rustc_hir_typeck/src/errors.rs

@@ -501,6 +501,7 @@ pub enum SuggestBoxing {
 #[suggestion(
     hir_typeck_suggest_ptr_null_mut,
     applicability = "maybe-incorrect",
+    style = "verbose",
     code = "core::ptr::null_mut()"
 )]
 pub struct SuggestPtrNullMut {

tests/ui/typeck/ptr-null-mutability-suggestions.stderr

@@ -2,10 +2,8 @@ error[E0308]: mismatched types
   --> $DIR/ptr-null-mutability-suggestions.rs:9:24
    |
 LL |     expecting_null_mut(ptr::null());
-   |     ------------------ ^^^^^^^^^^^
-   |     |                  |
-   |     |                  types differ in mutability
-   |     |                  help: consider using `core::ptr::null_mut` instead: `core::ptr::null_mut()`
+   |     ------------------ ^^^^^^^^^^^ types differ in mutability
+   |     |
    |     arguments to this function are incorrect
    |
    = note: expected raw pointer `*mut u8`
@@ -15,6 +13,10 @@ note: function defined here
    |
 LL | fn expecting_null_mut(_: *mut u8) {}
    |    ^^^^^^^^^^^^^^^^^^ ----------
+help: consider using `core::ptr::null_mut` instead
+   |
+LL |     expecting_null_mut(core::ptr::null_mut());
+   |                        ~~~~~~~~~~~~~~~~~~~~~
 
 error: aborting due to 1 previous error