Fix FieldtypePage for empty value and derefAsPageOrFalse setting.

Author: dadish

src/Type/Fieldtype/FieldtypePage.php

@@ -2,6 +2,7 @@
 
 use GraphQL\Deferred;
 use ProcessWire\Page;
+use ProcessWire\PageArray;
 use ProcessWire\FieldtypePage as PWFieldtypePage;
 use ProcessWire\GraphQL\Cache;
 use ProcessWire\GraphQL\Type\Inputfield\InputfieldPage;
@@ -37,17 +38,24 @@ public static function field($field)
         'description' => $desc,
         'type' => self::type($field),
         'resolve' => function ($value, $args, $context, $info) use ($field) {
+          $field->derefAsPage = PWFieldtypePage::derefAsPageArray;
           $data = $value->getArray();
           if (isset($data[$field->name])) {
-            PagesBuffer::add($field->name, $data[$field->name]);
+            $data = $data[$field->name];
+            if (!empty($data)) {
+              PagesBuffer::add($field->name, $data);
+            }
           }
           return new Deferred(function () use ($value, $field, $info) {
             $finderOptions = PageArrayType::getFinderOptions($info);
             PagesBuffer::loadPages($field->name, $finderOptions);
             $fieldName = $field->name;
             $field = \ProcessWire\wire('fields')->get($fieldName);
-            $field->derefAsPage = PWFieldtypePage::derefAsPageArray;
-            return $value->$fieldName->find(SelectorType::parseValue(""));
+            $value = $value->$fieldName;
+            if (!$value instanceof PageArray) {
+              return new PageArray();
+            }
+            return $value->find(SelectorType::parseValue(""));
           });
         }
       ];

test/Field/Page/Fieldtype/FieldtypePage/FieldtypePageCaseThreeTest.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace ProcessWire\GraphQL\Test\Field\Page\Fieldtype;
+
+/**
+ * Test the case when FieldtypePage:derefAsPageOrFalse is set
+ * and the value is empty.
+ */
+
+use ProcessWire\FieldtypePage;
+use \ProcessWire\GraphQL\Test\GraphQLTestCase;
+use \ProcessWire\GraphQL\Utils;
+
+class FieldtypePageCaseThreeTest extends GraphQLTestCase {
+
+  const settings = [
+    'login' => 'admin',
+    'legalTemplates' => ['skyscraper', 'architect'],
+    'legalFields' => ['architects'],
+    'access' => [
+      'fields' => [
+        [
+          'name' => 'architects',
+          'derefAsPage' => FieldtypePage::derefAsPageOrFalse,
+        ]
+      ]
+    ]
+  ];
+
+  public function testValue()
+  {
+		$skyscraper = Utils::pages()->get("template=skyscraper, architects.count=0");
+
+		// wake up the architects value
+		// which will set it to false
+		$skyscraper->architects;
+
+		$query = "{
+  		skyscraper (s: \"id=$skyscraper->id\") {
+  			list {
+  				architects {
+  					list {
+  						id
+  						name
+  					}
+  				}
+  			}
+  		}
+  	}";
+  	$res = self::execute($query);
+  	assertEquals(
+  		0,
+  		count($res->data->skyscraper->list[0]->architects->list),
+  		'Returns empty architect page array.'
+  	);
+
+    assertObjectNotHasAttribute('errors', $res, 'There are errors.');
+  }
+
+}

test/Field/Page/Fieldtype/FieldtypePage/FieldtypePageCaseTwoTest.php

@@ -8,7 +8,6 @@
  */
 
 use \ProcessWire\GraphQL\Test\GraphQLTestCase;
-use \ProcessWire\GraphQL\Test\Field\Page\Fieldtype\Traits\FieldtypeTestTrait;
 use \ProcessWire\GraphQL\Utils;
 
 class FieldtypePageCaseTwoTest extends GraphQLTestCase {
@@ -18,10 +17,6 @@ class FieldtypePageCaseTwoTest extends GraphQLTestCase {
     'legalTemplates' => ['skyscraper', 'architect'],
     'legalFields' => ['architects'],
   ];
-  const FIELD_NAME = 'architects';
-  const FIELD_TYPE = 'FieldtypePage';
-
-  use FieldtypeTestTrait;
 
   public function testValue()
   {