Rename VecDeque's rotate_left and rotate_right parameters

library/alloc/src/collections/vec_deque/mod.rs

@@ -2283,21 +2283,21 @@ impl<T, A: Allocator> VecDeque<T, A> {
         unsafe { slice::from_raw_parts_mut(ptr.add(self.head), self.len) }
     }
 
-    /// Rotates the double-ended queue `mid` places to the left.
+    /// Rotates the double-ended queue `n` places to the left.
     ///
     /// Equivalently,
-    /// - Rotates item `mid` into the first position.
-    /// - Pops the first `mid` items and pushes them to the end.
-    /// - Rotates `len() - mid` places to the right.
+    /// - Rotates item `n` into the first position.
+    /// - Pops the first `n` items and pushes them to the end.
+    /// - Rotates `len() - n` places to the right.
     ///
     /// # Panics
     ///
-    /// If `mid` is greater than `len()`. Note that `mid == len()`
+    /// If `n` is greater than `len()`. Note that `n == len()`
     /// does _not_ panic and is a no-op rotation.
     ///
     /// # Complexity
     ///
-    /// Takes `*O*(min(mid, len() - mid))` time and no extra space.
+    /// Takes `*O*(min(n, len() - n))` time and no extra space.
     ///
     /// # Examples
     ///
@@ -2316,31 +2316,31 @@ impl<T, A: Allocator> VecDeque<T, A> {
     /// assert_eq!(buf, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
     /// ```
     #[stable(feature = "vecdeque_rotate", since = "1.36.0")]
-    pub fn rotate_left(&mut self, mid: usize) {
-        assert!(mid <= self.len());
-        let k = self.len - mid;
-        if mid <= k {
-            unsafe { self.rotate_left_inner(mid) }
+    pub fn rotate_left(&mut self, n: usize) {
+        assert!(n <= self.len());
+        let k = self.len - n;
+        if n <= k {
+            unsafe { self.rotate_left_inner(n) }
         } else {
             unsafe { self.rotate_right_inner(k) }
         }
     }
 
-    /// Rotates the double-ended queue `k` places to the right.
+    /// Rotates the double-ended queue `n` places to the right.
     ///
     /// Equivalently,
-    /// - Rotates the first item into position `k`.
-    /// - Pops the last `k` items and pushes them to the front.
-    /// - Rotates `len() - k` places to the left.
+    /// - Rotates the first item into position `n`.
+    /// - Pops the last `n` items and pushes them to the front.
+    /// - Rotates `len() - n` places to the left.
     ///
     /// # Panics
     ///
-    /// If `k` is greater than `len()`. Note that `k == len()`
+    /// If `n` is greater than `len()`. Note that `n == len()`
     /// does _not_ panic and is a no-op rotation.
     ///
     /// # Complexity
     ///
-    /// Takes `*O*(min(k, len() - k))` time and no extra space.
+    /// Takes `*O*(min(n, len() - n))` time and no extra space.
     ///
     /// # Examples
     ///
@@ -2359,13 +2359,13 @@ impl<T, A: Allocator> VecDeque<T, A> {
     /// assert_eq!(buf, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
     /// ```
     #[stable(feature = "vecdeque_rotate", since = "1.36.0")]
-    pub fn rotate_right(&mut self, k: usize) {
-        assert!(k <= self.len());
-        let mid = self.len - k;
-        if k <= mid {
-            unsafe { self.rotate_right_inner(k) }
+    pub fn rotate_right(&mut self, n: usize) {
+        assert!(n <= self.len());
+        let k = self.len - n;
+        if n <= k {
+            unsafe { self.rotate_right_inner(n) }
         } else {
-            unsafe { self.rotate_left_inner(mid) }
+            unsafe { self.rotate_left_inner(k) }
         }
     }
 

library/alloc/src/collections/vec_deque/tests.rs

@@ -351,14 +351,14 @@ fn test_rotate_left_right() {
 }
 
 #[test]
-#[should_panic = "assertion failed: mid <= self.len()"]
+#[should_panic = "assertion failed: n <= self.len()"]
 fn test_rotate_left_panic() {
     let mut tester: VecDeque<_> = (1..=10).collect();
     tester.rotate_left(tester.len() + 1);
 }
 
 #[test]
-#[should_panic = "assertion failed: k <= self.len()"]
+#[should_panic = "assertion failed: n <= self.len()"]
 fn test_rotate_right_panic() {
     let mut tester: VecDeque<_> = (1..=10).collect();
     tester.rotate_right(tester.len() + 1);