Rollup merge of rust-lang#121648 - jieyouxu:from-into-raw-parts-docs, r=Nilstrieb

Update Vec and String `{from,into}_raw_parts`-family docs

- Fix documentation argument order to match the code argument order for consistency.
- Add return argument description for `{Vec,String}::into_raw_parts` to match their `from*` counterparts.

Author: matthiaskrgr

library/alloc/src/string.rs

@@ -864,7 +864,7 @@ impl String {
         }
     }
 
-    /// Decomposes a `String` into its raw components.
+    /// Decomposes a `String` into its raw components: `(pointer, length, capacity)`.
     ///
     /// Returns the raw pointer to the underlying data, the length of
     /// the string (in bytes), and the allocated capacity of the data
@@ -896,7 +896,7 @@ impl String {
         self.vec.into_raw_parts()
     }
 
-    /// Creates a new `String` from a length, capacity, and pointer.
+    /// Creates a new `String` from a pointer, a length and a capacity.
     ///
     /// # Safety
     ///

library/alloc/src/vec/mod.rs

@@ -481,7 +481,7 @@ impl<T> Vec<T> {
         Self::with_capacity_in(capacity, Global)
     }
 
-    /// Creates a `Vec<T>` directly from a pointer, a capacity, and a length.
+    /// Creates a `Vec<T>` directly from a pointer, a length, and a capacity.
     ///
     /// # Safety
     ///
@@ -672,7 +672,7 @@ impl<T, A: Allocator> Vec<T, A> {
         Vec { buf: RawVec::with_capacity_in(capacity, alloc), len: 0 }
     }
 
-    /// Creates a `Vec<T, A>` directly from a pointer, a capacity, a length,
+    /// Creates a `Vec<T, A>` directly from a pointer, a length, a capacity,
     /// and an allocator.
     ///
     /// # Safety
@@ -786,7 +786,7 @@ impl<T, A: Allocator> Vec<T, A> {
         unsafe { Vec { buf: RawVec::from_raw_parts_in(ptr, capacity, alloc), len: length } }
     }
 
-    /// Decomposes a `Vec<T>` into its raw components.
+    /// Decomposes a `Vec<T>` into its raw components: `(pointer, length, capacity)`.
     ///
     /// Returns the raw pointer to the underlying data, the length of
     /// the vector (in elements), and the allocated capacity of the
@@ -824,7 +824,7 @@ impl<T, A: Allocator> Vec<T, A> {
         (me.as_mut_ptr(), me.len(), me.capacity())
     }
 
-    /// Decomposes a `Vec<T>` into its raw components.
+    /// Decomposes a `Vec<T>` into its raw components: `(pointer, length, capacity, allocator)`.
     ///
     /// Returns the raw pointer to the underlying data, the length of the vector (in elements),
     /// the allocated capacity of the data (in elements), and the allocator. These are the same