Fix typo in expandIndexed (#160)

* Fix typo in expandIndex
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 088e838..1958535 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.15.0-nullsafety.5
+
+* Fix typo in extension method `expandIndexed`.
+
 ## 1.15.0-nullsafety.4
 
 * Allow prerelease versions of the `2.12.x` sdk.
diff --git a/lib/src/list_extensions.dart b/lib/src/list_extensions.dart
index c1f4af0..f61d610 100644
--- a/lib/src/list_extensions.dart
+++ b/lib/src/list_extensions.dart
@@ -165,7 +165,7 @@
   ///
   /// Like [Iterable.expand] except that the callback function is supplied with
   /// both the index and the element.
-  Iterable<R> expendIndexed<R>(
+  Iterable<R> expandIndexed<R>(
       Iterable<R> Function(int index, E element) expand) sync* {
     for (var index = 0; index < length; index++) {
       yield* expand(index, this[index]);
diff --git a/pubspec.yaml b/pubspec.yaml
index 74c7f1c..cd30d3d 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: collection
-version: 1.15.0-nullsafety.4
+version: 1.15.0-nullsafety.5
 
 description: Collections and utilities functions and classes related to collections.
 homepage: https://www.github.com/dart-lang/collection