Add withDefault to MorphOne relations.

src/Illuminate/Database/Eloquent/Relations/BelongsTo.php

@@ -5,17 +5,11 @@
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Collection;
+use Illuminate\Database\Eloquent\Relations\Concerns\HasDefault;
 
 class BelongsTo extends Relation
 {
-    /**
-     * Indicates if a default model instance should be used.
-     *
-     * Alternatively, may be a Closure or array.
-     *
-     * @var \Closure|array|bool
-     */
-    protected $withDefault;
+    use HasDefault;
 
     /**
      * The child model instance of the relation.
@@ -164,31 +158,6 @@ public function initRelation(array $models, $relation)
         return $models;
     }
 
-    /**
-     * Get the default value for this relation.
-     *
-     * @param  \Illuminate\Database\Eloquent\Model  $model
-     * @return \Illuminate\Database\Eloquent\Model|null
-     */
-    protected function getDefaultFor(Model $model)
-    {
-        if (! $this->withDefault) {
-            return;
-        }
-
-        $instance = $this->related->newInstance();
-
-        if (is_callable($this->withDefault)) {
-            return call_user_func($this->withDefault, $instance) ?: $instance;
-        }
-
-        if (is_array($this->withDefault)) {
-            $instance->forceFill($this->withDefault);
-        }
-
-        return $instance;
-    }
-
     /**
      * Match the eagerly loaded results to their parents.
      *
@@ -327,19 +296,6 @@ protected function relationHasIncrementingId()
                                 $this->related->getKeyType() === 'int';
     }
 
-    /**
-     * Return a new model instance in case the relationship does not exist.
-     *
-     * @param  \Closure|array|bool  $callback
-     * @return $this
-     */
-    public function withDefault($callback = true)
-    {
-        $this->withDefault = $callback;
-
-        return $this;
-    }
-
     /**
      * Get the foreign key of the relationship.
      *
@@ -389,4 +345,15 @@ public function getRelation()
     {
         return $this->relation;
     }
+
+    /**
+     * Make a new related instance for the given model.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $parent
+     * @return \Illuminate\Database\Eloquent\Model
+     */
+    protected function newRelatedInstanceFor(Model $parent)
+    {
+        return $this->related->newInstance();
+    }
 }

src/Illuminate/Database/Eloquent/Relations/Concerns/HasDefault.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace Illuminate\Database\Eloquent\Relations\Concerns;
+
+use Illuminate\Database\Eloquent\Model;
+
+trait HasDefault
+{
+    /**
+     * Indicates if a default model instance should be used.
+     *
+     * Alternatively, may be a Closure or array.
+     *
+     * @var \Closure|array|bool
+     */
+    protected $withDefault;
+
+    /**
+     * Return a new model instance in case the relationship does not exist.
+     *
+     * @param  \Closure|array|bool  $callback
+     * @return $this
+     */
+    public function withDefault($callback = true)
+    {
+        $this->withDefault = $callback;
+
+        return $this;
+    }
+
+    /**
+     * Get the default value for this relation.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $parent
+     * @return \Illuminate\Database\Eloquent\Model|null
+     */
+    protected function getDefaultFor(Model $parent)
+    {
+        if (! $this->withDefault) {
+            return;
+        }
+
+        $instance = $this->newRelatedInstanceFor($parent);
+
+        if (is_callable($this->withDefault)) {
+            return call_user_func($this->withDefault, $instance) ?: $instance;
+        }
+
+        if (is_array($this->withDefault)) {
+            $instance->forceFill($this->withDefault);
+        }
+
+        return $instance;
+    }
+
+    /**
+     * Make a new related instance for the given model.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $parent
+     * @return \Illuminate\Database\Eloquent\Model
+     */
+    abstract protected function newRelatedInstanceFor(Model $parent);
+}

src/Illuminate/Database/Eloquent/Relations/HasOne.php

@@ -4,17 +4,11 @@
 
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Collection;
+use Illuminate\Database\Eloquent\Relations\Concerns\HasDefault;
 
 class HasOne extends HasOneOrMany
 {
-    /**
-     * Indicates if a default model instance should be used.
-     *
-     * Alternatively, may be a Closure or array.
-     *
-     * @var \Closure|array|bool
-     */
-    protected $withDefault;
+    use HasDefault;
 
     /**
      * Get the results of the relationship.
@@ -42,33 +36,6 @@ public function initRelation(array $models, $relation)
         return $models;
     }
 
-    /**
-     * Get the default value for this relation.
-     *
-     * @param  \Illuminate\Database\Eloquent\Model  $model
-     * @return \Illuminate\Database\Eloquent\Model|null
-     */
-    protected function getDefaultFor(Model $model)
-    {
-        if (! $this->withDefault) {
-            return;
-        }
-
-        $instance = $this->related->newInstance()->setAttribute(
-            $this->getForeignKeyName(), $model->getAttribute($this->localKey)
-        );
-
-        if (is_callable($this->withDefault)) {
-            return call_user_func($this->withDefault, $instance) ?: $instance;
-        }
-
-        if (is_array($this->withDefault)) {
-            $instance->forceFill($this->withDefault);
-        }
-
-        return $instance;
-    }
-
     /**
      * Match the eagerly loaded results to their parents.
      *
@@ -83,15 +50,14 @@ public function match(array $models, Collection $results, $relation)
     }
 
     /**
-     * Return a new model instance in case the relationship does not exist.
+     * Make a new related instance for the given model.
      *
-     * @param  \Closure|array|bool  $callback
-     * @return $this
+     * @param  \Illuminate\Database\Eloquent\Model  $parent
+     * @return \Illuminate\Database\Eloquent\Model
      */
-    public function withDefault($callback = true)
+    public function newRelatedInstanceFor(Model $parent)
     {
-        $this->withDefault = $callback;
-
-        return $this;
+        return $this->related->newInstance()
+            ->setAttribute($this->getForeignKeyName(), $parent->{$this->localKey});
     }
 }

src/Illuminate/Database/Eloquent/Relations/MorphOne.php

@@ -2,18 +2,22 @@
 
 namespace Illuminate\Database\Eloquent\Relations;
 
+use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Collection;
+use Illuminate\Database\Eloquent\Relations\Concerns\HasDefault;
 
 class MorphOne extends MorphOneOrMany
 {
+    use HasDefault;
+
     /**
      * Get the results of the relationship.
      *
      * @return mixed
      */
     public function getResults()
     {
-        return $this->query->first();
+        return $this->query->first() ?: $this->getDefaultFor($this->parent);
     }
 
     /**
@@ -26,7 +30,7 @@ public function getResults()
     public function initRelation(array $models, $relation)
     {
         foreach ($models as $model) {
-            $model->setRelation($relation, null);
+            $model->setRelation($relation, $this->getDefaultFor($model));
         }
 
         return $models;
@@ -44,4 +48,17 @@ public function match(array $models, Collection $results, $relation)
     {
         return $this->matchOne($models, $results, $relation);
     }
+
+    /**
+     * Make a new related instance for the given model.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $parent
+     * @return \Illuminate\Database\Eloquent\Model
+     */
+    public function newRelatedInstanceFor(Model $parent)
+    {
+        return $this->related->newInstance()
+            ->setAttribute($this->getForeignKeyName(), $parent->{$this->localKey})
+            ->setAttribute($this->getMorphType(), $this->morphClass);
+    }
 }