Add suggestion for some #[deprecated] items

Author: dima74

library/alloc/src/lib.rs

@@ -118,6 +118,7 @@
 #![feature(const_waker)]
 #![feature(core_intrinsics)]
 #![feature(core_panic)]
+#![feature(deprecated_suggestion)]
 #![feature(dispatch_from_dyn)]
 #![feature(error_generic_member_access)]
 #![feature(error_in_core)]

library/alloc/src/slice.rs

@@ -592,7 +592,7 @@ impl<T> [T] {
     /// ```
     #[rustc_allow_incoherent_impl]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[deprecated(since = "1.3.0", note = "renamed to join")]
+    #[deprecated(since = "1.3.0", note = "renamed to join", suggestion = "join")]
     pub fn connect<Separator>(&self, sep: Separator) -> <Self as Join<Separator>>::Output
     where
         Self: Join<Separator>,

library/core/src/error.rs

@@ -114,7 +114,8 @@ pub trait Error: Debug + Display {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[deprecated(
         since = "1.33.0",
-        note = "replaced by Error::source, which can support downcasting"
+        note = "replaced by Error::source, which can support downcasting",
+        suggestion = "source"
     )]
     #[allow(missing_docs)]
     fn cause(&self) -> Option<&dyn Error> {

library/core/src/mem/mod.rs

@@ -413,7 +413,7 @@ pub const unsafe fn size_of_val_raw<T: ?Sized>(val: *const T) -> usize {
 #[inline]
 #[must_use]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(note = "use `align_of` instead", since = "1.2.0")]
+#[deprecated(note = "use `align_of` instead", since = "1.2.0", suggestion = "align_of")]
 pub fn min_align_of<T>() -> usize {
     intrinsics::min_align_of::<T>()
 }
@@ -436,7 +436,7 @@ pub fn min_align_of<T>() -> usize {
 #[inline]
 #[must_use]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(note = "use `align_of_val` instead", since = "1.2.0")]
+#[deprecated(note = "use `align_of_val` instead", since = "1.2.0", suggestion = "align_of_val")]
 pub fn min_align_of_val<T: ?Sized>(val: &T) -> usize {
     // SAFETY: val is a reference, so it's a valid raw pointer
     unsafe { intrinsics::min_align_of_val(val) }

library/core/src/str/mod.rs

@@ -993,7 +993,7 @@ impl str {
 
     /// An iterator over the lines of a string.
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[deprecated(since = "1.4.0", note = "use lines() instead now")]
+    #[deprecated(since = "1.4.0", note = "use lines() instead now", suggestion = "lines")]
     #[inline]
     #[allow(deprecated)]
     pub fn lines_any(&self) -> LinesAny<'_> {

library/std/src/os/unix/process.rs

@@ -109,7 +109,11 @@ pub trait CommandExt: Sealed {
     ///
     /// [`pre_exec`]: CommandExt::pre_exec
     #[stable(feature = "process_exec", since = "1.15.0")]
-    #[deprecated(since = "1.37.0", note = "should be unsafe, use `pre_exec` instead")]
+    #[deprecated(
+        since = "1.37.0",
+        note = "should be unsafe, use `pre_exec` instead",
+        suggestion = "pre_exec"
+    )]
     fn before_exec<F>(&mut self, f: F) -> &mut process::Command
     where
         F: FnMut() -> io::Result<()> + Send + Sync + 'static,

library/std/src/sync/condvar.rs

@@ -305,7 +305,11 @@ impl Condvar {
     /// }
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[deprecated(since = "1.6.0", note = "replaced by `std::sync::Condvar::wait_timeout`")]
+    #[deprecated(
+        since = "1.6.0",
+        note = "replaced by `std::sync::Condvar::wait_timeout`",
+        suggestion = "wait_timeout"
+    )]
     pub fn wait_timeout_ms<'a, T>(
         &self,
         guard: MutexGuard<'a, T>,

library/std/src/thread/mod.rs

@@ -825,7 +825,7 @@ pub fn panicking() -> bool {
 /// thread::sleep_ms(2000);
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(since = "1.6.0", note = "replaced by `std::thread::sleep`")]
+#[deprecated(since = "1.6.0", note = "replaced by `std::thread::sleep`", suggestion = "sleep")]
 pub fn sleep_ms(ms: u32) {
     sleep(Duration::from_millis(ms as u64))
 }
@@ -1004,7 +1004,11 @@ pub fn park() {
 ///
 /// See the [park documentation][`park`] for more detail.
 #[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(since = "1.6.0", note = "replaced by `std::thread::park_timeout`")]
+#[deprecated(
+    since = "1.6.0",
+    note = "replaced by `std::thread::park_timeout`",
+    suggestion = "park_timeout"
+)]
 pub fn park_timeout_ms(ms: u32) {
     park_timeout(Duration::from_millis(ms as u64))
 }

tests/ui/deprecation/issue-84637-deprecated-associated-function.fixed

@@ -6,4 +6,6 @@ fn main() {
     let _foo = str::trim_start("   aoeu"); //~ ERROR use of deprecated method `core::str::<impl str>::trim_left`: superseded by `trim_start` [deprecated]
 
     let _bar = "   aoeu".trim_start(); //~ ERROR use of deprecated method `core::str::<impl str>::trim_left`: superseded by `trim_start` [deprecated]
+
+    let _baz = ["a", "b"].join(" "); //~ ERROR use of deprecated method `std::slice::<impl [T]>::connect`: renamed to join [deprecated]
 }

tests/ui/deprecation/issue-84637-deprecated-associated-function.rs

@@ -6,4 +6,6 @@ fn main() {
     let _foo = str::trim_left("   aoeu"); //~ ERROR use of deprecated method `core::str::<impl str>::trim_left`: superseded by `trim_start` [deprecated]
 
     let _bar = "   aoeu".trim_left(); //~ ERROR use of deprecated method `core::str::<impl str>::trim_left`: superseded by `trim_start` [deprecated]
+
+    let _baz = ["a", "b"].connect(" "); //~ ERROR use of deprecated method `std::slice::<impl [T]>::connect`: renamed to join [deprecated]
 }

tests/ui/deprecation/issue-84637-deprecated-associated-function.stderr

@@ -25,5 +25,16 @@ help: replace the use of the deprecated method
 LL |     let _bar = "   aoeu".trim_start();
    |                          ~~~~~~~~~~
 
-error: aborting due to 2 previous errors
+error: use of deprecated method `std::slice::<impl [T]>::connect`: renamed to join
+  --> $DIR/issue-84637-deprecated-associated-function.rs:10:27
+   |
+LL |     let _baz = ["a", "b"].connect(" ");
+   |                           ^^^^^^^
+   |
+help: replace the use of the deprecated method
+   |
+LL |     let _baz = ["a", "b"].join(" ");
+   |                           ~~~~
+
+error: aborting due to 3 previous errors