Merge pull request #8 from plank/fix-newest-id-attribute

fix: revisionable_id on null

README.md

@@ -171,6 +171,43 @@ withoutRevisions()
 
 This query scope is used to query the models without taking revisioning into consideration.
 
+### Dynamic Relationships
+
+Inspired by https://reinink.ca/articles/dynamic-relationships-in-laravel-using-subqueries, this package supplies a few
+dynamic relationships as a convenience for navigating through a model's revision history. The following scopes will run
+subqueries to get the additional columns and eagerload the corresponding relations, saving you the hassle of caching 
+them on each of the tables for your revisionable models. As a fallback when these scopes are not applied, we use get 
+mutators to run queries and fetch the same columns, making sure the relations are always available but at the expense 
+of running a bit more queries. *NOTE: when applying these scopes, you will have extra columns in your models attributes, 
+**any update or insert operations will not work.***
+
+#### withNewestAt($until, $since)
+```php
+/**
+ * @param $until Checkpoint|Carbon|string
+ * @param $since Checkpoint|Carbon|string
+ */
+withNewestAt($until = null, $since = null)
+```
+This scope will retrieve the id of the newest model given the until / since constraints. Stored in the newest_id
+attribute, this allows you to use `->newest()` relation as a quick way to navigate to that model. Defaults to the 
+newest model in the revision history.
+
+#### withNewest()
+This scope is a shortcut of `withNewestAt` with the default parameters. Uses the same attribute, mutator and relation.
+
+#### withInitial()
+This scope will retrieve the id of the initial model from its revision history. Stored in the initial_id attribute, 
+this allows you to use `->initial()` relation as a quick way to navigate to that first item in the revision history. 
+
+#### withPrevious()
+This scope will retrieve the id of the previous model from its revision history. Stored in the previous_id attribute, 
+this allows you to use `->previous()` relation as a quick way to navigate to that previous item in the revision history. 
+
+#### withNext()
+This scope will retrieve the id of the next model from its revision history. Stored in the next_id attribute, 
+this allows you to use `->next()` relation as a quick way to navigate to that next item in the revision history. 
+
 ### Revision Metadata & Uniqueness
 As a workaround to some package compatibility issues, this package offers a convenient way to store the values of some
 columns as ```metadata``` on the ```revisions``` table. The primary use-case for this feature is to deal with columns or 

src/Concerns/HasRevisions.php

@@ -247,8 +247,8 @@ public function getNewestIdAttribute($value)
         if ($value !== null || array_key_exists('newest_id', $this->attributes)) {
             return $value;
         }
-        // dependency on latest boolean column, alternative to using max id
-        return $this->revisions()->where('latest', true)->first()->revisionable_id;
+        // when value isn't set by extra subselect scope, fetch from relations
+        return $this->revision->newest->revisionable_id ?? null;
     }
 
 
@@ -413,9 +413,7 @@ public function performRevision()
     protected function replicateRelationsTo(Model $copy)
     {
         $relationHelper = resolve(RelationHelper::class);
-
-        $excluded = $this->getExcludedRelations();
-        $relations = collect($relationHelper::getModelRelations($this))->map->type->except($excluded);
+        $relations = collect($relationHelper::getModelRelations($this))->map->type;
 
         foreach ($relations as $relation => $type) {
             $shortType = substr($type, strrpos($type, '\\') + 1);

src/Helpers/RelationHelper.php

@@ -161,11 +161,12 @@ public static function isChildMultiple(string $relation): bool
      * Not just the eager loaded ones present in the $relations Eloquent property.
      *
      * @param Model|class-string $model
+     * @param array $except
      * @param bool $refresh
      * @return array
      * @throws ReflectionException
      */
-    public static function getModelRelations($model, bool $refresh = false): array
+    public static function getModelRelations($model, array $except = [], bool $refresh = false): array
     {
         /** @var class-string $class */
         $class = ($model instanceof Model) ? get_class($model) : $model;
@@ -176,6 +177,10 @@ public static function getModelRelations($model, bool $refresh = false): array
             return static::$relations[$class];
         }
 
+        if (method_exists($model, 'getExcludedRelations')) {
+            $except = array_merge($except, $model->getExcludedRelations());
+        }
+
         static::$relations[$class] = [];
 
         foreach (get_class_methods($model) as $method) {
@@ -199,7 +204,7 @@ public static function getModelRelations($model, bool $refresh = false): array
             $code = substr($code, $begin, strrpos($code, '}') - $begin + 1);
 
             foreach (static::$relationTypes as $type) {
-                if (stripos($code, '$this->'.$type.'(')) {
+                if (stripos($code, '$this->'.$type.'(') && !in_array($method, $except, true)) {
                     $relation = $model->$method();
 
                     if ($relation instanceof Relation) {

src/Models/Revision.php

@@ -26,6 +26,7 @@
  * @property-read int|null $all_revisions_count
  * @property-read \Illuminate\Database\Eloquent\Collection|Revision[] $otherRevisions
  * @property-read int|null $other_revisions_count
+ * @property-read Revision|null $newest
  * @property-read Revision|null $next
  * @property-read Revision|null $previous
  * @property-read Checkpoint|null $checkpoint
@@ -234,6 +235,18 @@ public function next(): HasOne
         return $this->hasOne(static::class, 'previous_revision_id', $this->getKeyName());
     }
 
+    /**
+     * Return latest revision
+     *
+     * @return HasOne
+     */
+    public function newest(): HasOne
+    {
+        return $this->hasOne(static::class, 'revisionable_type', 'revisionable_type')
+            ->where('original_revisionable_id', $this->original_revisionable_id)
+            ->where('latest', true)->latest();
+    }
+
     /**
      * Returns true if this is the most current revision for an item
      *

tests/Feature/RevisionObservablesTest.php

@@ -141,8 +141,14 @@ public function force_deleted_posts_preserves_revision_history(): void
         $r1->refresh();
         $this->assertEquals(0, $r1->next()->count());
         $this->assertNull($r1->previous_revision_id);
-        $this->assertCount(1, Post::withoutRevisions()->get());
+        $posts = Post::withoutRevisions()->get();
+        $this->assertCount(1, $posts);
         $this->assertCount(1, Revision::all());
+        $post = $posts->first();
+        $post->forceDelete();
+        $this->assertCount(0, $r1->otherRevisions()->get());
+        $this->assertNull(null, $post->newest()->get());
+        $this->assertCount(0, Post::withoutRevisions()->get());
     }
 
     /**