Add add() method

Author: Jarek Jakubowski

src/JarJak/Collection/Collection.php

@@ -70,6 +70,15 @@ public function filter(?\Closure $callback = null)
         return static::from(array_filter($this->toArray(), $callback, ARRAY_FILTER_USE_BOTH));
     }
 
+    public function add($item): self
+    {
+        $newIndex = $this->count();
+
+        return static::from($this->toArray() + [
+            $newIndex => $item,
+        ]);
+    }
+
     public function remove($element)
     {
         $array = $this->toArray();

tests/CollectionTest.php

@@ -106,4 +106,15 @@ public function testFirst(): void
         $this->assertSame($collection->first(), 1);
         $this->assertSame(55, $sum);
     }
+
+    public function testAdd(): void
+    {
+        $collection = Collection::from(range(1, 3));
+        $collection = $collection->add(5);
+        $collection = $collection->add(5);
+        $collection = $collection->add(3);
+
+        $this->assertSame($collection->count(), 6);
+        $this->assertSame($collection->toArray(), [1, 2, 3, 5, 5, 3]);
+    }
 }