From e8c40352c49ea63f6a1f0fa5487ff92030782f9b Mon Sep 17 00:00:00 2001
From: Jan Iwanow <iwanow.jan@gmail.com>
Date: Mon, 5 Oct 2020 20:13:58 +0700
Subject: [PATCH 1/3] bumped PHP version to 7.0

---
 docker-compose.yaml.example | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docker-compose.yaml.example b/docker-compose.yaml.example
index 81f84d1..8edf255 100644
--- a/docker-compose.yaml.example
+++ b/docker-compose.yaml.example
@@ -23,7 +23,7 @@ services:
       POSTGRES_USER: user
       POSTGRES_PASSWORD: userpass
   php:
-    image: php:5.6-cli
+    image: php:7.0-cli
     tty: true
     command: /bin/sh
     volumes:

From 66a7af5f25eeb8636ad98d186732423cb5b33e14 Mon Sep 17 00:00:00 2001
From: Jan Iwanow <iwanow.jan@gmail.com>
Date: Mon, 5 Oct 2020 20:14:41 +0700
Subject: [PATCH 2/3] small tweaks for readability

---
 src/Models/Entity.php | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/Models/Entity.php b/src/Models/Entity.php
index df423c6..f0abb02 100644
--- a/src/Models/Entity.php
+++ b/src/Models/Entity.php
@@ -166,7 +166,7 @@ public function setParentIdAttribute($value)
         }
 
         $parentId = $this->getParentIdColumn();
-        $this->previousParentId = isset($this->original[$parentId]) ? $this->original[$parentId] : null;
+        $this->previousParentId = $this->original[$parentId] ?? null;
         $this->attributes[$parentId] = $value;
     }
 
@@ -212,7 +212,7 @@ public function setPositionAttribute($value)
         }
 
         $position = $this->getPositionColumn();
-        $this->previousPosition = isset($this->original[$position]) ? $this->original[$position] : null;
+        $this->previousPosition = $this->original[$position] ?? null;
         $this->attributes[$position] = max(0, (int) $value);
     }
 
@@ -298,7 +298,7 @@ public static function boot()
             $entity->previousPosition = null;
 
             $descendant = $entity->getKey();
-            $ancestor = isset($entity->parent_id) ? $entity->parent_id : $descendant;
+            $ancestor = $entity->parent_id ?? $descendant;
 
             $entity->closure->insertNode($ancestor, $descendant);
         });
@@ -883,7 +883,7 @@ public function getChildrenRange($from, $to = null, array $columns = ['*'])
     public function addChild(EntityInterface $child, $position = null, $returnChild = false)
     {
         if ($this->exists) {
-            $position = $position !== null ? $position : $this->getLatestChildPosition();
+            $position = $position ?? $this->getLatestChildPosition();
 
             $child->moveTo($position, $this);
         }
@@ -1596,7 +1596,7 @@ private function buildSiblingQuery(Builder $builder, $id, callable $positionCall
     public function addSibling(EntityInterface $sibling, $position = null, $returnSibling = false)
     {
         if ($this->exists) {
-            $position = $position === null ? static::getLatestPosition($this) : $position;
+            $position = $position ?? static::getLatestPosition($this);
 
             $sibling->moveTo($position, $this->parent_id);
 
@@ -1623,7 +1623,7 @@ public function addSiblings(array $siblings, $from = null)
             return $this;
         }
 
-        $from = $from === null ? static::getLatestPosition($this) : $from;
+        $from = $from ?? static::getLatestPosition($this);
 
         $this->transactional(function () use ($siblings, &$from) {
             foreach ($siblings as $sibling) {
@@ -1876,7 +1876,7 @@ public function deleteSubtree($withSelf = false, $forceDelete = false)
      * @param  array $models
      * @return \Illuminate\Database\Eloquent\Collection
      */
-    public function newCollection(array $models = array())
+    public function newCollection(array $models = [])
     {
         return new Collection($models);
     }

From c4f53b95f2924c6d41e9d70b6c32a0e1bf240a94 Mon Sep 17 00:00:00 2001
From: Jan Iwanow <iwanow.jan@gmail.com>
Date: Mon, 5 Oct 2020 20:18:31 +0700
Subject: [PATCH 3/3] introduced the "parent" relationship

---
 src/Models/Entity.php | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/Models/Entity.php b/src/Models/Entity.php
index f0abb02..9f4435a 100644
--- a/src/Models/Entity.php
+++ b/src/Models/Entity.php
@@ -5,6 +5,7 @@
 use Illuminate\Database\Eloquent\Model as Eloquent;
 use Franzose\ClosureTable\Contracts\EntityInterface;
 use Franzose\ClosureTable\Extensions\Collection;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Support\Arr;
 use InvalidArgumentException;
@@ -354,6 +355,16 @@ public function getParent(array $columns = ['*'])
         return $this->exists ? $this->find($this->parent_id, $columns) : null;
     }
 
+    /**
+     * Returns many-to-one relationship to the direct ancestor.
+     *
+     * @return BelongsTo
+     */
+    public function parent()
+    {
+        return $this->belongsTo(get_class($this), $this->getParentIdColumn());
+    }
+
     /**
      * Returns query builder for ancestors.
      *