Fix: ErasablePtr::with()

* remove references of the unerased value
* fix memory leaks in tests by unerase/drop the erased values

Author: cehteh

crates/erasable/src/lib.rs

@@ -201,6 +201,7 @@ pub unsafe trait ErasablePtr {
     /// };
     ///
     /// assert_eq!(*cloned, 123);
+    /// # unsafe {<Rc<i32> as ErasablePtr>::unerase(erased)}; // drop it
     /// ```
     ///
     /// The main purpose of this function is to be able implement recursive types that would
@@ -215,7 +216,7 @@ pub unsafe trait ErasablePtr {
         Self: Sized,
         F: FnOnce(&Self) -> T,
     {
-        f(&ManuallyDrop::new(&Self::unerase(*this)))
+        f(&ManuallyDrop::new(Self::unerase(*this)))
     }
 
     /// Run a closure on a mutable borrow of the real pointer.  Unlike the `Thin<T>` wrapper

crates/erasable/tests/smoke.rs

@@ -34,7 +34,7 @@ fn thinning() {
 }
 
 #[test]
-fn withfn() {
+fn with_fn() {
     let boxed: Box<Big> = Default::default();
 
     let erased: ErasedPtr = ErasablePtr::erase(boxed);
@@ -44,6 +44,9 @@ fn withfn() {
             assert_eq!(*bigbox, Default::default());
         })
     }
+
+    // drop it, otherwise we would leak memory here
+    unsafe { <Box<Big> as ErasablePtr>::unerase(erased) };
 }
 
 #[test]