fix exception in collection if model use soft delete

src/PostgresEngine.php

@@ -217,7 +217,10 @@ protected function performSearch(Builder $builder, $perPage = 0, $page = 1)
             ->whereRaw("$indexColumn @@ query")
             ->orderBy('rank', 'desc')
             ->orderBy($builder->model->getKeyName());
-
+        //if model use soft delete - without trashed
+        if (method_exists($builder->model, 'getDeletedAtColumn')) {
+            $query->where($builder->model->getDeletedAtColumn(), null);
+        }
         if ($perPage > 0) {
             $query->skip(($page - 1) * $perPage)
                 ->limit($perPage);

tests/PostgresEngineTest.php

@@ -37,6 +37,7 @@ public function test_update_adds_object_to_index()
         $table->shouldReceive('where')
             ->with('id', '=', 1)
             ->andReturnSelf();
+
         $table->shouldReceive('update')
             ->with(['searchable' => 'foo']);
 
@@ -98,6 +99,25 @@ public function test_search()
         $engine->search($builder);
     }
 
+    public function test_search_with_soft_delete()
+    {
+        list($engine, $db) = $this->getEngine();
+
+        $table = $this->setDbExpectations($db);
+
+        $table->shouldReceive('skip')->with(0)->andReturnSelf()
+            ->shouldReceive('limit')->with(5)->andReturnSelf()
+            ->shouldReceive('where')->with('bar', 1)->andReturnSelf()
+            ->shouldReceive('where')->with('deleted_at', null);
+
+        $db->shouldReceive('select')->with(null, ['foo', 1]);
+
+        $builder = new Builder(new TestWithSoftDeleteModel(), 'foo');
+        $builder->where('bar', 1)->take(5);
+
+        $engine->search($builder);
+    }
+
     public function test_map_correctly_maps_results_to_models()
     {
         list($engine) = $this->getEngine();
@@ -227,3 +247,59 @@ public function searchableAdditionalArray()
         return $this->searchableAdditionalArray;
     }
 }
+
+class TestWithSoftDeleteModel extends Model
+{
+    use \Illuminate\Database\Eloquent\SoftDeletes;
+    public $id = 1;
+
+    public $text = 'Foo';
+
+    protected $searchableOptions = [
+        'rank' => [
+            'fields' => [
+                'nullable' => 'B',
+            ],
+        ],
+    ];
+
+    protected $searchableAdditionalArray = [];
+
+    public function searchableAs()
+    {
+        return 'searchable';
+    }
+
+    public function getKeyName()
+    {
+        return 'id';
+    }
+
+    public function getKey()
+    {
+        return $this->id;
+    }
+
+    public function getTable()
+    {
+        return 'table';
+    }
+
+    public function toSearchableArray()
+    {
+        return [
+            'text' => $this->text,
+            'nullable' => null,
+        ];
+    }
+
+    public function searchableOptions()
+    {
+        return $this->searchableOptions;
+    }
+
+    public function searchableAdditionalArray()
+    {
+        return $this->searchableAdditionalArray;
+    }
+}