InlineFragment: read selectionset from QueryBuilderInterface

src/FieldTrait.php

@@ -67,5 +67,9 @@ protected function constructSelectionSet(): string
 
         return $attributesString;
     }
-}
 
+    public function getSelectionSet()
+    {
+        return $this->selectionSet;
+    }
+}

src/InlineFragment.php

@@ -2,6 +2,8 @@
 
 namespace GraphQL;
 
+use GraphQL\QueryBuilder\QueryBuilderInterface;
+
 /**
  * Class InlineFragment
  *
@@ -23,21 +25,32 @@ class InlineFragment extends NestableObject
      */
     protected $typeName;
 
+    /**
+     * @var QueryBuilderInterface|null
+     */
+    protected $queryBuilder;
+
     /**
      * InlineFragment constructor.
      *
      * @param string $typeName
+     * @param QueryBuilderInterface|null $queryBuilder
      */
-    public function __construct(string $typeName)
+    public function __construct(string $typeName, ?QueryBuilderInterface $queryBuilder = null)
     {
         $this->typeName = $typeName;
+        $this->queryBuilder = $queryBuilder;
     }
 
     /**
      *
      */
     public function __toString()
     {
+        if ($this->queryBuilder !== null) {
+            $this->setSelectionSet($this->queryBuilder->getQuery()->getSelectionSet());
+        }
+
         return sprintf(static::FORMAT, $this->typeName, $this->constructSelectionSet());
     }
 
@@ -50,4 +63,4 @@ protected function setAsNested()
     {
         // TODO: Remove this method, it's purely tech debt
     }
-}
+}

tests/InlineFragmentTest.php

@@ -4,6 +4,7 @@
 
 use GraphQL\InlineFragment;
 use GraphQL\Query;
+use GraphQL\QueryBuilder\QueryBuilder;
 use PHPUnit\Framework\TestCase;
 
 /**
@@ -37,6 +38,7 @@ public function testConvertToString()
             (string) $fragment
         );
     }
+
     /**
      * @covers \GraphQL\InlineFragment::__construct
      * @covers \GraphQL\InlineFragment::setSelectionSet
@@ -84,4 +86,28 @@ public function testConvertNestedFragmentToString()
             (string) $fragment
         );
     }
-}
+
+    /**
+     * @covers \GraphQL\InlineFragment::__construct
+     * @covers \GraphQL\InlineFragment::setSelectionSet
+     * @covers \GraphQL\InlineFragment::getSelectionSet
+     * @covers \GraphQL\InlineFragment::constructSelectionSet
+     * @covers \GraphQL\InlineFragment::__toString
+     */
+    public function testConvertQueryBuilderToString()
+    {
+        $queryBuilder = new QueryBuilder();
+
+        $fragment = new InlineFragment('Test', $queryBuilder);
+        $queryBuilder->selectField('field1');
+        $queryBuilder->selectField('field2');
+
+        $this->assertEquals(
+            '... on Test {
+field1
+field2
+}',
+            (string) $fragment
+        );
+    }
+}