An entity without relation to other entity must not have joins

In our case `JoinOnNoInversedBy` cannot have a `joins` field because the
entity NoInversedBy has no relation to any other entity.

Fixes #23

Author: popovserhii

src/Factory/Type/JoinOnTypeFactory.php

@@ -46,15 +46,21 @@ public function create(string $className, string $typeName): Type
         $type = new InputObjectType([
             'name' => $typeName,
             'fields' => function () use ($className): array {
-                return [
+                $fields = [
                     [
                         'name' => 'type',
                         'type' => $this->types->get('JoinType'),
                         'defaultValue' => 'innerJoin',
                     ],
-                    $this->filterGroupJoinTypeFactory->getField($className),
                     $this->filterGroupConditionTypeFactory->getField($className),
                 ];
+
+                // Only create join type, if there is anything to join on
+                if ($this->filterGroupJoinTypeFactory->canCreate($className)) {
+                    $fields[] = $this->filterGroupJoinTypeFactory->getField($className);
+                }
+
+                return $fields;
             },
         ]);
 

tests/Blog/Model/Post.php

@@ -7,6 +7,7 @@
 use DateTime;
 use Doctrine\ORM\Mapping as ORM;
 use GraphQL\Doctrine\Annotation as API;
+use GraphQLTests\Doctrine\Blog\Model\Special\NoInversedBy;
 
 /**
  * A blog post with title and body
@@ -57,6 +58,13 @@ final class Post extends AbstractModel
      */
     private $user;
 
+    /**
+     * @var NoInversedBy
+     *
+     * @ORM\ManyToOne(targetEntity="GraphQLTests\Doctrine\Blog\Model\Special\NoInversedBy")
+     */
+    private $noInversedBy;
+
     /**
      * Set title
      *

tests/Blog/Model/Special/NoInversedBy.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GraphQLTests\Doctrine\Blog\Model\Special;
+
+use Doctrine\ORM\Mapping as ORM;
+use GraphQLTests\Doctrine\Blog\Model\AbstractModel;
+
+/**
+ * @ORM\Entity
+ */
+final class NoInversedBy extends AbstractModel
+{
+}

tests/data/PostFilter.graphqls

@@ -169,28 +169,35 @@ input InOperatorString {
   not: Boolean = false
 }
 
+input JoinOnNoInversedBy {
+  type: JoinType = innerJoin
+
+  """Conditions to be applied on fields"""
+  conditions: [NoInversedByFilterGroupCondition!]
+}
+
 input JoinOnPost {
   type: JoinType = innerJoin
 
+  """Conditions to be applied on fields"""
+  conditions: [PostFilterGroupCondition!]
+
   """
   Optional joins to either filter the query or fetch related objects from DB in a single query
   """
   joins: PostFilterGroupJoin
-
-  """Conditions to be applied on fields"""
-  conditions: [PostFilterGroupCondition!]
 }
 
 input JoinOnUser {
   type: JoinType = innerJoin
 
+  """Conditions to be applied on fields"""
+  conditions: [UserFilterGroupCondition!]
+
   """
   Optional joins to either filter the query or fetch related objects from DB in a single query
   """
   joins: UserFilterGroupJoin
-
-  """Conditions to be applied on fields"""
-  conditions: [UserFilterGroupCondition!]
 }
 
 """Join types to be used in DQL"""
@@ -269,6 +276,41 @@ input ModuloOperatorInt {
   value: Int!
 }
 
+"""Type to specify conditions on fields"""
+input NoInversedByFilterGroupCondition {
+  creationDate: NoInversedByFilterGroupConditionCreationDate
+  id: NoInversedByFilterGroupConditionId
+}
+
+"""Type to specify a condition on a specific field"""
+input NoInversedByFilterGroupConditionCreationDate {
+  between: BetweenOperatorDateTime
+  equal: EqualOperatorDateTime
+  greater: GreaterOperatorDateTime
+  greaterOrEqual: GreaterOrEqualOperatorDateTime
+  in: InOperatorDateTime
+  less: LessOperatorDateTime
+  lessOrEqual: LessOrEqualOperatorDateTime
+  like: LikeOperatorDateTime
+  null: NullOperatorDateTime
+  group: GroupOperatorDateTime
+}
+
+"""Type to specify a condition on a specific field"""
+input NoInversedByFilterGroupConditionId {
+  between: BetweenOperatorID
+  equal: EqualOperatorID
+  greater: GreaterOperatorID
+  greaterOrEqual: GreaterOrEqualOperatorID
+  in: InOperatorID
+  less: LessOperatorID
+  lessOrEqual: LessOrEqualOperatorID
+  like: LikeOperatorID
+  null: NullOperatorID
+  group: GroupOperatorID
+  modulo: ModuloOperatorInt
+}
+
 input NullOperatorBoolean {
   not: Boolean = false
 }
@@ -316,6 +358,7 @@ input PostFilterGroupCondition {
   status: PostFilterGroupConditionStatus
   id: PostFilterGroupConditionId
   user: PostFilterGroupConditionUser
+  noInversedBy: PostFilterGroupConditionNoInversedBy
   custom: PostFilterGroupConditionCustom
 }
 
@@ -367,6 +410,22 @@ input PostFilterGroupConditionId {
   modulo: ModuloOperatorInt
 }
 
+"""Type to specify a condition on a specific field"""
+input PostFilterGroupConditionNoInversedBy {
+  have: HaveOperatorID
+  empty: EmptyOperatorID
+  between: BetweenOperatorID
+  equal: EqualOperatorID
+  greater: GreaterOperatorID
+  greaterOrEqual: GreaterOrEqualOperatorID
+  in: InOperatorID
+  less: LessOperatorID
+  lessOrEqual: LessOrEqualOperatorID
+  like: LikeOperatorID
+  null: NullOperatorID
+  group: GroupOperatorID
+}
+
 """Type to specify a condition on a specific field"""
 input PostFilterGroupConditionPublicationDate {
   between: BetweenOperatorDateTime
@@ -428,6 +487,7 @@ input PostFilterGroupConditionUser {
 """Type to specify join tables in a filter"""
 input PostFilterGroupJoin {
   user: JoinOnUser
+  noInversedBy: JoinOnNoInversedBy
 }
 
 input SearchOperatorString {