Iterators: add ReverseArray

src/Iterators/README.md

@@ -88,3 +88,20 @@ $wait = new ActiveWait(0.3); // wait 0.3s = 300ms
 
 $wait->run(fn(): bool => random_int(1, 5) === 4);
 ```
+
+# ReverseArray
+
+Run array from end to begin.
+
+```php
+use h4kuna\DataType\Iterators\ReverseArray;
+
+$iterator = new ReverseArray([1, 2, 3]);
+
+foreach ($iterator as $item) {
+    echo $item;
+}
+// 3
+// 2
+// 1
+```

src/Iterators/ReverseArray.php

@@ -0,0 +1,49 @@
+<?php declare(strict_types=1);
+
+namespace h4kuna\DataType\Iterators;
+
+use Iterator;
+
+/**
+ * @implements Iterator<mixed, mixed>
+ */
+final class ReverseArray implements Iterator
+{
+	/**
+	 * @param array<mixed, mixed> $array
+	 */
+	public function __construct(private array $array)
+	{
+	}
+
+
+	public function current(): mixed
+	{
+		return current($this->array);
+	}
+
+
+	public function next(): void
+	{
+		prev($this->array);
+	}
+
+
+	public function key(): mixed
+	{
+		return key($this->array);
+	}
+
+
+	public function valid(): bool
+	{
+		return key($this->array) !== null;
+	}
+
+
+	public function rewind(): void
+	{
+		end($this->array);
+	}
+
+}

tests/src/Unit/Iterators/ReverseArrayTest.php

@@ -0,0 +1,49 @@
+<?php declare(strict_types=1);
+
+namespace h4kuna\DataType\Tests\Unit\Iterators;
+
+use h4kuna\DataType\Iterators\ReverseArray;
+use Tester\Assert;
+use Tester\TestCase;
+
+require_once __DIR__ . '/bootstrap.php';
+
+/**
+ * @testCase
+ */
+final class ReverseArrayTest extends TestCase
+{
+	/**
+	 * @return array<mixed>
+	 */
+	protected function basicProvider(): array
+	{
+		return [
+			[
+				[1, 2, 3],
+				[2 => 3, 1 => 2, 0 => 1],
+			],
+			[
+				[],
+				[],
+			],
+		];
+	}
+
+
+	/**
+	 * @dataProvider basicProvider
+	 * @param array<mixed> $source
+	 * @param array<mixed> $expected
+	 */
+	public function testBasic(array $source, array $expected): void
+	{
+		$actual = [];
+		foreach (new ReverseArray($source) as $k => $v) {
+			$actual[$k] = $v;
+		}
+		Assert::same($expected, $actual);
+	}
+}
+
+(new ReverseArrayTest())->run();