Rollup merge of rust-lang#130800 - bjoernager:const-mut-cursor, r=joshtriplett

matthiaskrgr · web-flow · commit 3f03a0f3fcdb · 2024-11-20T20:10:12.000+01:00
Mark `get_mut` and `set_position` in `std::io::Cursor` as const. Relevant tracking issue: rust-lang#130801 The methods `get_mut` and `set_position` can trivially be marked as const due to rust-lang#57349 being stabilised.
diff --git a/std/src/io/cursor.rs b/std/src/io/cursor.rs
@@ -153,7 +153,8 @@ impl<T> Cursor<T> {
     /// let reference = buff.get_mut();
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn get_mut(&mut self) -> &mut T {
+    #[rustc_const_unstable(feature = "const_mut_cursor", issue = "130801")]
+    pub const fn get_mut(&mut self) -> &mut T {
         &mut self.inner
     }
 
@@ -200,7 +201,8 @@ impl<T> Cursor<T> {
     /// assert_eq!(buff.position(), 4);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn set_position(&mut self, pos: u64) {
+    #[rustc_const_unstable(feature = "const_mut_cursor", issue = "130801")]
+    pub const fn set_position(&mut self, pos: u64) {
         self.pos = pos;
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -153,7 +153,8 @@ impl<T> Cursor<T> {`
`153`	`153`	`/// let reference = buff.get_mut();`
`154`	`154`	/// ```
`155`	`155`	`#[stable(feature = "rust1", since = "1.0.0")]`
`156`		`- pub fn get_mut(&mut self) -> &mut T {`
	`156`	`+ #[rustc_const_unstable(feature = "const_mut_cursor", issue = "130801")]`
	`157`	`+ pub const fn get_mut(&mut self) -> &mut T {`
`157`	`158`	`&mut self.inner`
`158`	`159`	`}`
`159`	`160`
`@@ -200,7 +201,8 @@ impl<T> Cursor<T> {`
`200`	`201`	`/// assert_eq!(buff.position(), 4);`
`201`	`202`	/// ```
`202`	`203`	`#[stable(feature = "rust1", since = "1.0.0")]`
`203`		`- pub fn set_position(&mut self, pos: u64) {`
	`204`	`+ #[rustc_const_unstable(feature = "const_mut_cursor", issue = "130801")]`
	`205`	`+ pub const fn set_position(&mut self, pos: u64) {`
`204`	`206`	`self.pos = pos;`
`205`	`207`	`}`
`206`	`208`	`}`