Rollup merge of rust-lang#67873 - Dylan-DPC:feature/change-remove-to-partial, r=Amanieu

change remove to have a PartialEq bound

Addresses [comment](rust-lang#67727 (comment)).

References rust-lang#40062

r? @Amanieu

Author: Dylan-DPC

src/liballoc/tests/lib.rs

@@ -11,6 +11,7 @@
 #![feature(associated_type_bounds)]
 #![feature(binary_heap_into_iter_sorted)]
 #![feature(binary_heap_drain_sorted)]
+#![feature(vec_remove_item)]
 
 use std::collections::hash_map::DefaultHasher;
 use std::hash::{Hash, Hasher};

src/liballoc/tests/vec.rs

@@ -131,6 +131,21 @@ fn test_extend_ref() {
     assert_eq!(v, [1, 2, 3, 4, 5, 6, 7]);
 }
 
+#[test]
+fn test_remove_item() {
+    let mut v = vec![1, 2, 3];
+    v.remove_item(&1);
+
+    assert_eq!(v.len(), 2);
+    assert_eq!(v, [2, 3]);
+
+    let mut w = vec![1, 2, 3];
+    w.remove_item(&4);
+
+    assert_eq!(w.len(), 3);
+    w.remove_item(&4);
+}
+
 #[test]
 fn test_slice_from_mut() {
     let mut values = vec![1, 2, 3, 4, 5];

src/liballoc/vec.rs

@@ -1688,7 +1688,9 @@ impl<T: PartialEq> Vec<T> {
     pub fn dedup(&mut self) {
         self.dedup_by(|a, b| a == b)
     }
+}
 
+impl<T> Vec<T> {
     /// Removes the first instance of `item` from the vector if the item exists.
     ///
     /// # Examples
@@ -1702,7 +1704,10 @@ impl<T: PartialEq> Vec<T> {
     /// assert_eq!(vec, vec![2, 3, 1]);
     /// ```
     #[unstable(feature = "vec_remove_item", reason = "recently added", issue = "40062")]
-    pub fn remove_item(&mut self, item: &T) -> Option<T> {
+    pub fn remove_item<V>(&mut self, item: &V) -> Option<T>
+    where
+        T: PartialEq<V>,
+    {
         let pos = self.iter().position(|x| *x == *item)?;
         Some(self.remove(pos))
     }