Introduce UnionBuilder

Author: simPod

src/Builder/UnionBuilder.php

@@ -0,0 +1,63 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SimPod\GraphQLUtils\Builder;
+
+use GraphQL\Type\Definition\ObjectType;
+use GraphQL\Type\Definition\ResolveInfo;
+
+class UnionBuilder extends TypeBuilder
+{
+    /** @var callable(object, mixed, ResolveInfo)|null */
+    private $resolveType;
+
+    /** @var ObjectType[] */
+    private $types;
+
+    /**
+     * @return static
+     */
+    public static function create(string $name) : self
+    {
+        return new static($name);
+    }
+
+    /**
+     * @see ResolveInfo Force Jetbrains IDE use
+     *
+     * @param callable(mixed):ObjectType $resolveType
+     *
+     * @return static
+     */
+    public function setResolveType(callable $resolveType) : self
+    {
+        $this->resolveType = $resolveType;
+
+        return $this;
+    }
+
+    /**
+     * @param ObjectType[] $types
+     *
+     * @return static
+     */
+    public function setTypes(array $types) : self
+    {
+        $this->types = $types;
+
+        return $this;
+    }
+
+    /**
+     * @return mixed[]
+     */
+    public function build() : array
+    {
+        $parameters                = parent::build();
+        $parameters['types']       = $this->types;
+        $parameters['resolveType'] = $this->resolveType;
+
+        return $parameters;
+    }
+}

tests/Builder/UnionBuilderTest.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SimPod\GraphQLUtils\Tests\Builder;
+
+use GraphQL\Type\Definition\ObjectType;
+use PHPUnit\Framework\TestCase;
+use SimPod\GraphQLUtils\Builder\ObjectBuilder;
+use SimPod\GraphQLUtils\Builder\UnionBuilder;
+
+final class UnionBuilderTest extends TestCase
+{
+    public function testCreate() : void
+    {
+        $name = 'InterfaceA';
+
+        $builder     = UnionBuilder::create($name);
+        $description = 'Description';
+
+        $typeA = new ObjectType(ObjectBuilder::create('TypeA')->build());
+        $typeB = new ObjectType(ObjectBuilder::create('TypeB')->build());
+
+        $union = $builder
+            ->setDescription($description)
+            ->setTypes(
+                [$typeA, $typeB]
+            )
+            ->setResolveType(
+                static function (bool $value) use ($typeA, $typeB) : ObjectType {
+                    return $value ? $typeA : $typeB;
+                }
+            )
+            ->build();
+
+        self::assertSame($name, $union['name']);
+        self::assertSame($description, $union['description']);
+
+        self::assertArrayHasKey('types', $union);
+        self::assertIsArray($union['types']);
+        self::assertCount(2, $union['types']);
+
+        self::assertArrayHasKey('resolveType', $union);
+        self::assertSame($typeA, $union['resolveType'](true));
+        self::assertSame($typeB, $union['resolveType'](false));
+    }
+}