Support creating collections directly from Doctrine Collections

CHANGELOG.md

@@ -7,6 +7,7 @@ Change Log
 - Added the factory methods `Collection::from()` and `Collection::empty()`.
 - Added helper methods `Collection::isEmpty()` and `Collection::isNotEmpty()`.
 - Added `Collection::reverse()` helper to reverse the order of the collection.
+- Support creating collections from Doctrine Collections using `Collection::fromDoctrine()`.
 
 # 0.2.0
 - Minimum PHP version bumped to 8.1.

composer.json

@@ -9,7 +9,8 @@
     "issues": "https://github.com/headsnet/collections/issues"
   },
   "require": {
-    "php": ">=8.1"
+    "php": ">=8.1",
+    "doctrine/collections": ">1"
   },
   "require-dev": {
     "phpunit/phpunit": "^10.5",

src/AbstractImmutableCollection.php

@@ -4,6 +4,7 @@
 namespace Headsnet\Collections;
 
 use ArrayIterator;
+use Doctrine\Common\Collections\Collection as DoctrineCollection;
 use Headsnet\Collections\Exception\InvalidTypeException;
 use Headsnet\Collections\Exception\ItemNotFoundException;
 use Headsnet\Collections\Exception\OutOfRangeException;
@@ -55,6 +56,16 @@ public static function from(array $items): static
         return new $class($items);
     }
 
+    /**
+     * @param DoctrineCollection<int, TValue> $items
+     */
+    public static function fromDoctrine(DoctrineCollection $items): static
+    {
+        $class = static::class;
+
+        return new $class($items->toArray());
+    }
+
     public static function empty(): static
     {
         $class = static::class;

tests/unit/ImmutableCollectionTest.php

@@ -3,13 +3,14 @@
 
 namespace Headsnet\Collections\Test;
 
+use Doctrine\Common\Collections\ArrayCollection;
 use Headsnet\Collections\Exception\InvalidTypeException;
 use Headsnet\Collections\Exception\ItemNotFoundException;
 use Headsnet\Collections\Test\Fixtures\AugmentedImmutableCollection;
+use Headsnet\Collections\Test\Fixtures\CompanionObject;
 use Headsnet\Collections\Test\Fixtures\DummyCollectionItem;
 use Headsnet\Collections\Test\Fixtures\DummyImmutableCollection;
 use Headsnet\Collections\Test\Fixtures\OtherCollectionItem;
-use Headsnet\Collections\Test\Fixtures\CompanionObject;
 use PHPUnit\Framework\TestCase;
 
 /**
@@ -68,6 +69,18 @@ public function test_can_create_collection_with_extra_properties(): void
         $this->assertEquals($someValueObject1, $sut->companionObject);
     }
 
+    public function test_can_create_collection_from_doctrine_collection(): void
+    {
+        $collectionItem1 = new DummyCollectionItem();
+        $collectionItem2 = new DummyCollectionItem();
+        $doctrineCollection = new ArrayCollection([$collectionItem1, $collectionItem2]);
+
+        $sut = DummyImmutableCollection::fromDoctrine($doctrineCollection);
+
+        $this->assertEquals($collectionItem1, $sut->firstOrFail());
+        $this->assertEquals($collectionItem2, $sut->lastOrFail());
+    }
+
     public function test_is_empty_check_is_correct(): void
     {
         $sut = DummyImmutableCollection::empty();