code style fixes

Author: F001

src/libcore/cell.rs

@@ -507,10 +507,12 @@ impl<T: ?Sized> Cell<T> {
     /// ```
     /// #![feature(as_cell)]
     /// use std::cell::Cell;
-    /// let slice: &mut [i32] = &mut [1,2,3];
+    ///
+    /// let slice: &mut [i32] = &mut [1, 2, 3];
     /// let cell_slice: &Cell<[i32]> = Cell::from_mut(slice);
     /// assert_eq!(cell_slice.len(), 3);
-    /// let slice_cell : &[Cell<i32>] = &cell_slice[..];
+    ///
+    /// let slice_cell: &[Cell<i32>] = &cell_slice[..];
     /// assert_eq!(slice_cell.len(), 3);
     /// ```
     #[inline]

src/test/run-pass/rfc-1789-as-cell/from-mut.rs

@@ -13,9 +13,10 @@
 use std::cell::Cell;
 
 fn main() {
-    let slice: &mut [i32] = &mut [1,2,3];
+    let slice: &mut [i32] = &mut [1, 2, 3];
     let cell_slice: &Cell<[i32]> = Cell::from_mut(slice);
     assert_eq!(cell_slice.len(), 3);
-    let sub_slice : &[Cell<i32>] = &cell_slice[1..];
+
+    let sub_slice: &[Cell<i32>] = &cell_slice[1..];
     assert_eq!(sub_slice.len(), 2);
 }