Remove Deref from MapMut

PiperOrigin-RevId: 599329208

rust/map.rs

@@ -11,7 +11,6 @@ use crate::{
     __runtime::InnerMapMut,
 };
 use std::marker::PhantomData;
-use std::ops::Deref;
 
 #[repr(transparent)]
 pub struct MapView<'msg, K: ?Sized, V: ?Sized> {
@@ -27,15 +26,6 @@ impl<'msg, K: ?Sized, V: ?Sized> Clone for MapView<'msg, K, V> {
     }
 }
 
-impl<'msg, K: ?Sized, V: ?Sized> Deref for MapMut<'msg, K, V> {
-    type Target = MapView<'msg, K, V>;
-    fn deref(&self) -> &Self::Target {
-        // SAFETY:
-        //   - `MapView<'msg, K, V>` is `#[repr(transparent)]` over `RawMap`.
-        unsafe { &*(&self.inner.raw as *const RawMap as *const MapView<'msg, K, V>) }
-    }
-}
-
 unsafe impl<'msg, K: ?Sized, V: ?Sized> Sync for MapView<'msg, K, V> {}
 unsafe impl<'msg, K: ?Sized, V: ?Sized> Send for MapView<'msg, K, V> {}
 
@@ -233,6 +223,14 @@ where
         Self { inner, _phantom_key: PhantomData, _phantom_value: PhantomData }
     }
 
+    pub fn len(self) -> usize {
+        self.as_view().len()
+    }
+
+    pub fn is_empty(self) -> bool {
+        self.len() == 0
+    }
+
     pub fn insert<'a, 'b>(
         &mut self,
         key: impl Into<View<'a, K>>,