feat: Add MapIterableAggregate and FilterIterableAggregate.

README.md

@@ -21,9 +21,11 @@ The missing PHP iterators.
 * `ClosureIterator`: `ClosureIterator(callable $callable, array $arguments = [])`
 * `ClosureIteratorAggregate`: `ClosureIteratorAggregate(callable $callable, array $arguments = [])`
 * `ConcatIterableAggregate`
+* `FilterIterableAggregate`
 * `InterruptableIterableAggregate`: `InterruptableIterableAggregate(iterable $iterable)`
 * `IterableIterator`: `IterableIterator(iterable $iterable)`
 * `IterableIteratorAggregate`: `IterableIteratorAggregate(iterable $iterable)`
+* `MapIterableAggregate`
 * `MersenneTwisterRNGIteratorAggregate`
 * `MultipleIterableAggregate`
 * `PackIterableAggregate`
@@ -72,6 +74,20 @@ foreach ($iterator as $key => $value); // This will work.
 foreach ($iterator as $key => $value); // This will also work.
 ```
 
+### FilterIterableAggregate
+
+```php
+<?php
+
+$iterator = (new FilterIterableAggregate(
+    range(0, 5),
+    static fn (int $v, int $key, iterable $iterable): bool =>
+        0 === (($v + 2 * $key + count($iterable)) % 2)
+));
+
+foreach ($iterator as $filteredValue) {} // 0, 2, 4
+```
+
 ### InterruptableIterableAggregate
 
 Let you break the iterator at anytime.
@@ -101,6 +117,25 @@ foreach ($iterator as $generator => [$key, $value]) {
 }
 ```
 
+### MapIterableAggregate
+
+```php
+<?php
+
+$iterator = (new MapIterableAggregate(
+    range('a', 'c'),
+    static fn (string $letter, int $key, iterable $iterable): string =>
+        sprintf(
+            '%s::%s::%s',
+            $key,
+            $letter,
+            gettype($iterable)
+        )
+));
+
+foreach ($iterator as $tranformedValue) {}
+```
+
 ### MersenneTwisterRNGIteratorAggregate
 
 ```php

src/FilterIterableAggregate.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace loophp\iterators;
+
+use Closure;
+use Generator;
+use IteratorAggregate;
+
+/**
+ * @template TKey
+ * @template T
+ *
+ * @implements IteratorAggregate<TKey, T>
+ */
+final class FilterIterableAggregate implements IteratorAggregate
+{
+    /**
+     * @var iterable<TKey, T>
+     */
+    private iterable $iterable;
+
+    /**
+     * @var Closure(T, TKey, iterable<TKey, T>): bool
+     */
+    private Closure $predicate;
+
+    /**
+     * @param iterable<TKey, T> $iterable
+     * @param (Closure(T, TKey, iterable<TKey, T>): bool) $predicate
+     */
+    public function __construct(iterable $iterable, Closure $predicate)
+    {
+        $this->iterable = $iterable;
+        $this->predicate = $predicate;
+    }
+
+    /**
+     * @return Generator<TKey, T>
+     */
+    public function getIterator(): Generator
+    {
+        foreach ($this->iterable as $key => $value) {
+            if (($this->predicate)($value, $key, $this->iterable)) {
+                yield $key => $value;
+            }
+        }
+    }
+}

src/MapIterableAggregate.php

@@ -0,0 +1,54 @@
+<?php
+
+/**
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace loophp\iterators;
+
+use Closure;
+use Generator;
+use IteratorAggregate;
+
+/**
+ * @template TKey
+ * @template T
+ * @template W
+ *
+ * @implements IteratorAggregate<TKey, W>
+ */
+final class MapIterableAggregate implements IteratorAggregate
+{
+    /**
+     * @var Closure(T, TKey, iterable<TKey, T>): W
+     */
+    private Closure $closure;
+
+    /**
+     * @var iterable<TKey, T>
+     */
+    private iterable $iterable;
+
+    /**
+     * @param iterable<TKey, T> $iterable
+     * @param (Closure(T, TKey, iterable<TKey, T>): W) $closure
+     */
+    public function __construct(iterable $iterable, Closure $closure)
+    {
+        $this->iterable = $iterable;
+        $this->closure = $closure;
+    }
+
+    /**
+     * @return Generator<TKey, W>
+     */
+    public function getIterator(): Generator
+    {
+        foreach ($this->iterable as $key => $value) {
+            yield $key => ($this->closure)($value, $key, $this->iterable);
+        }
+    }
+}

tests/unit/FilterIterableAggregateTest.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace tests\loophp\iterators;
+
+use loophp\iterators\FilterIterableAggregate;
+use PHPUnit\Framework\TestCase;
+use function count;
+
+/**
+ * @internal
+ * @coversDefaultClass \loophp\iterators
+ */
+final class FilterIterableAggregateTest extends TestCase
+{
+    public function testBasic(): void
+    {
+        $iterator = (new FilterIterableAggregate(
+            range(0, 5),
+            static fn (int $v, int $key, iterable $iterable): bool => 0 === (($v + 2 * $key + count($iterable)) % 2)
+        ));
+
+        $expected = [
+            0 => 0,
+            2 => 2,
+            4 => 4,
+        ];
+
+        self::assertSame($expected, iterator_to_array($iterator));
+    }
+}

tests/unit/MapIterableAggregateTest.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace tests\loophp\iterators;
+
+use loophp\iterators\MapIterableAggregate;
+use PHPUnit\Framework\TestCase;
+use function gettype;
+
+/**
+ * @internal
+ * @coversDefaultClass \loophp\iterators
+ */
+final class MapIterableAggregateTest extends TestCase
+{
+    public function testBasic(): void
+    {
+        $iterator = (new MapIterableAggregate(
+            range('a', 'c'),
+            static fn (string $letter, int $key, iterable $iterable): string => sprintf('%s::%s::%s', $key, $letter, gettype($iterable))
+        ));
+
+        $expected = [
+            '0::a::array',
+            '1::b::array',
+            '2::c::array',
+        ];
+
+        self::assertSame($expected, iterator_to_array($iterator));
+    }
+}