Add Run operation.

spec/drupol/collection/CollectionSpec.php

@@ -685,12 +685,48 @@ static function ($carry, $item) {
 
     public function it_can_run_an_operation(Operation $operation): void
     {
-        $operation
-            ->run($this)
-            ->shouldBeCalledOnce();
+        $square = new class() extends \drupol\collection\Operation\Operation {
+            public function run(CollectionInterface $collection)
+            {
+                return Collection::with(
+                    static function () use ($collection) {
+                        foreach ($collection as $item) {
+                            yield $item ** 2;
+                        }
+                    }
+                );
+            }
+        };
 
-        $this
-            ->run($operation);
+        $sqrt = new class() extends \drupol\collection\Operation\Operation {
+            public function run(CollectionInterface $collection)
+            {
+                return Collection::with(
+                    static function () use ($collection) {
+                        foreach ($collection as $item) {
+                            yield $item ** .5;
+                        }
+                    }
+                );
+            }
+        };
+
+        $map = new class() extends \drupol\collection\Operation\Operation {
+            public function run(CollectionInterface $collection)
+            {
+                return Collection::with(
+                    static function () use ($collection) {
+                        foreach ($collection as $item) {
+                            yield (int) $item;
+                        }
+                    }
+                );
+            }
+        };
+
+        $this::with(\range(1, 5))
+            ->run($square, $sqrt, $map)
+            ->shouldIterateAs(\range(1, 5));
     }
 
     public function it_can_skip(): void

src/Collection.php

@@ -34,6 +34,7 @@
 use drupol\collection\Operation\Range;
 use drupol\collection\Operation\Rebase;
 use drupol\collection\Operation\Reduce;
+use drupol\collection\Operation\Run;
 use drupol\collection\Operation\Skip;
 use drupol\collection\Operation\Slice;
 use drupol\collection\Operation\Walk;
@@ -301,7 +302,7 @@ public function reduce(callable $callback, $initial = null)
      */
     public function run(Operation ...$operations)
     {
-        return \array_reduce($operations, [$this, 'doRun'], $this);
+        return Run::with($operations)->run($this);
     }
 
     /**
@@ -377,22 +378,6 @@ public function zip(...$items): CollectionInterface
         return $this->run(Zip::with($items));
     }
 
-    /**
-     * Run an operation on the collection.
-     *
-     * @param \drupol\collection\Contract\Collection $collection
-     *   The collection.
-     * @param \drupol\collection\Contract\Operation $operation
-     *   The operation.
-     *
-     * @return mixed
-     *   The operation result.
-     */
-    private function doRun(CollectionInterface $collection, Operation $operation)
-    {
-        return $operation->run($collection);
-    }
-
     /**
      * Get items as an array.
      *

src/Operation/Run.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace drupol\collection\Operation;
+
+use drupol\collection\Contract\Collection as CollectionInterface;
+
+/**
+ * Class Run.
+ */
+final class Run extends Operation
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function run(CollectionInterface $collection)
+    {
+        [$operations] = $this->parameters;
+
+        return \array_reduce($operations, [$this, 'doRun'], $collection);
+    }
+
+    /**
+     * Run an operation on the collection.
+     *
+     * @param \drupol\collection\Contract\Collection $collection
+     *   The collection.
+     * @param \drupol\collection\Operation\Operation $operation
+     *   The operation.
+     *
+     * @return mixed
+     *   The operation result.
+     */
+    private function doRun(CollectionInterface $collection, Operation $operation)
+    {
+        return $operation->run($collection);
+    }
+}