From e1f5f26e8a76836bcb3af2e16818e2b6a8f7477f Mon Sep 17 00:00:00 2001
From: Josh Stone <cuviper@gmail.com>
Date: Mon, 26 Aug 2024 18:52:20 -0700
Subject: [PATCH 1/2] Add `first_entry` and `last_entry` similar to `BTreeMap`

---
 src/map.rs       | 14 ++++++++++++++
 src/map/tests.rs | 14 ++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/src/map.rs b/src/map.rs
index 85310934..956812e4 100644
--- a/src/map.rs
+++ b/src/map.rs
@@ -1098,6 +1098,13 @@ impl<K, V, S> IndexMap<K, V, S> {
         self.as_entries_mut().first_mut().map(Bucket::ref_mut)
     }
 
+    /// Get the first entry in the map for in-place manipulation.
+    ///
+    /// Computes in **O(1)** time.
+    pub fn first_entry(&mut self) -> Option<IndexedEntry<'_, K, V>> {
+        self.get_index_entry(0)
+    }
+
     /// Get the last key-value pair
     ///
     /// Computes in **O(1)** time.
@@ -1112,6 +1119,13 @@ impl<K, V, S> IndexMap<K, V, S> {
         self.as_entries_mut().last_mut().map(Bucket::ref_mut)
     }
 
+    /// Get the last entry in the map for in-place manipulation.
+    ///
+    /// Computes in **O(1)** time.
+    pub fn last_entry(&mut self) -> Option<IndexedEntry<'_, K, V>> {
+        self.get_index_entry(self.len().checked_sub(1)?)
+    }
+
     /// Remove the key-value pair by index
     ///
     /// Valid indices are *0 <= index < self.len()*
diff --git a/src/map/tests.rs b/src/map/tests.rs
index 49541181..fd62904d 100644
--- a/src/map/tests.rs
+++ b/src/map/tests.rs
@@ -391,6 +391,8 @@ fn get_index_entry() {
     let mut map = IndexMap::new();
 
     assert!(map.get_index_entry(0).is_none());
+    assert!(map.first_entry().is_none());
+    assert!(map.last_entry().is_none());
 
     map.insert(0, "0");
     map.insert(1, "1");
@@ -414,6 +416,18 @@ fn get_index_entry() {
     }
 
     assert_eq!(*map.get(&3).unwrap(), "4");
+
+    {
+        let e = map.first_entry().unwrap();
+        assert_eq!(*e.key(), 0);
+        assert_eq!(*e.get(), "0");
+    }
+
+    {
+        let e = map.last_entry().unwrap();
+        assert_eq!(*e.key(), 2);
+        assert_eq!(*e.get(), "2");
+    }
 }
 
 #[test]

From 264e5b73045b1f28d36f80c7e3d0bac63af5e887 Mon Sep 17 00:00:00 2001
From: Josh Stone <cuviper@gmail.com>
Date: Tue, 27 Aug 2024 08:50:05 -0700
Subject: [PATCH 2/2] Add doc aliases like `BTreeMap`/`BTreeSet`

---
 src/map.rs | 3 +++
 src/set.rs | 1 +
 2 files changed, 4 insertions(+)

diff --git a/src/map.rs b/src/map.rs
index 956812e4..b224aace 100644
--- a/src/map.rs
+++ b/src/map.rs
@@ -821,6 +821,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// This preserves the order of the remaining elements.
     ///
     /// Computes in **O(1)** time (average).
+    #[doc(alias = "pop_last")] // like `BTreeMap`
     pub fn pop(&mut self) -> Option<(K, V)> {
         self.core.pop()
     }
@@ -1087,6 +1088,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Get the first key-value pair
     ///
     /// Computes in **O(1)** time.
+    #[doc(alias = "first_key_value")] // like `BTreeMap`
     pub fn first(&self) -> Option<(&K, &V)> {
         self.as_entries().first().map(Bucket::refs)
     }
@@ -1108,6 +1110,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Get the last key-value pair
     ///
     /// Computes in **O(1)** time.
+    #[doc(alias = "last_key_value")] // like `BTreeMap`
     pub fn last(&self) -> Option<(&K, &V)> {
         self.as_entries().last().map(Bucket::refs)
     }
diff --git a/src/set.rs b/src/set.rs
index 835ccf02..7a8ac4df 100644
--- a/src/set.rs
+++ b/src/set.rs
@@ -708,6 +708,7 @@ impl<T, S> IndexSet<T, S> {
     /// This preserves the order of the remaining elements.
     ///
     /// Computes in **O(1)** time (average).
+    #[doc(alias = "pop_last")] // like `BTreeSet`
     pub fn pop(&mut self) -> Option<T> {
         self.map.pop().map(|(x, ())| x)
     }