Add distinct() dans rsample() methods.

spec/drupol/collection/CollectionSpec.php

@@ -308,6 +308,18 @@ public function it_can_count_its_items(): void
             ->shouldReturn(3);
     }
 
+    public function it_can_distinct(): void
+    {
+        $stdclass = new \stdClass();
+
+        $this
+            ->beConstructedWith([1, 1, 2, 2, 3, 3, $stdclass, $stdclass]);
+
+        $this
+            ->distinct()
+            ->shouldIterateAs([0 => 1, 2 => 2, 4 => 3, 6 => $stdclass]);
+    }
+
     public function it_can_filter_its_element(): void
     {
         $input = \array_merge([0, false], \range(1, 10));
@@ -803,6 +815,20 @@ static function ($carry, $item) {
             ->shouldIterateAs([0, 1, 3, 6, 10, 15]);
     }
 
+    public function it_can_rsample(): void
+    {
+        $this
+            ->beConstructedThrough('with', [\range(1, 10)]);
+
+        $this
+            ->rsample(1)
+            ->shouldHaveCount(10);
+
+        $this
+            ->rsample(.5)
+            ->shouldNotHaveCount(10);
+    }
+
     public function it_can_run_an_operation(Operation $operation): void
     {
         $square = new class() implements Operation {

src/Collection.php

@@ -14,6 +14,7 @@
 use drupol\collection\Operation\Combine;
 use drupol\collection\Operation\Contains;
 use drupol\collection\Operation\Count;
+use drupol\collection\Operation\Distinct;
 use drupol\collection\Operation\Filter;
 use drupol\collection\Operation\First;
 use drupol\collection\Operation\Flatten;
@@ -114,6 +115,18 @@ public function count(): int
 
     /**
      * {@inheritdoc}
+     *
+     * @return \drupol\collection\Contract\Collection
+     */
+    public function distinct(): BaseInterface
+    {
+        return new Collection($this->run(new Distinct()));
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @return \drupol\collection\Contract\Collection
      */
     public static function empty(): CollectionInterface
     {
@@ -320,6 +333,20 @@ public function reduction(callable $callback, $initial = null): BaseInterface
         return new Collection($this->run(new Reduction($callback, $initial)));
     }
 
+    /**
+     * {@inheritdoc}
+     *
+     * @return \drupol\collection\Contract\Collection
+     */
+    public function rsample($probability): BaseInterface
+    {
+        $callback = static function ($item) use ($probability) {
+            return (\mt_rand() / \mt_getrandmax()) < $probability;
+        };
+
+        return new Collection($this->run(new Filter($callback)));
+    }
+
     /**
      * {@inheritdoc}
      */

src/Contract/Collection.php

@@ -16,6 +16,7 @@ interface Collection extends
     Collapseable,
     Combineable,
     Containsable,
+    Distinctable,
     Filterable,
     Firstable,
     Flattenable,
@@ -38,6 +39,7 @@ interface Collection extends
     Rebaseable,
     Reduceable,
     Reductionable,
+    RSampleable,
     Skipable,
     Sliceable,
     Sortable,

src/Contract/Distinctable.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+namespace drupol\collection\Contract;
+
+/**
+ * Interface Distinctable.
+ */
+interface Distinctable
+{
+    /**
+     * @return \drupol\collection\Contract\Base
+     */
+    public function distinct(): Base;
+}

src/Contract/RSampleable.php

@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace drupol\collection\Contract;
+
+/**
+ * Interface RSampleable.
+ */
+interface RSampleable
+{
+    /**
+     * @param float $probability
+     *
+     * @return \drupol\collection\Contract\Base
+     */
+    public function rsample($probability): Base;
+}

src/Operation/Distinct.php

@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace drupol\collection\Operation;
+
+use drupol\collection\Collection;
+use drupol\collection\Contract\Operation;
+
+/**
+ * Class Distinct.
+ */
+final class Distinct implements Operation
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function on(iterable $collection)
+    {
+        return static function () use ($collection) {
+            $seen = new Collection([]);
+
+            foreach ($collection as $key => $value) {
+                if (true === $seen->contains($value)) {
+                    continue;
+                }
+
+                $seen = $seen
+                    ->append($value)
+                    ->rebase();
+
+                yield $key => $value;
+            }
+        };
+    }
+}