Make order by and select keyword rules use column aliases

See #34

src/Options/SearchStringOptions.php

@@ -99,6 +99,13 @@ public function getColumnRule($key): ?ColumnRule
         });
     }
 
+    public function getColumnNameFromAlias($alias): string
+    {
+        $columnRule = $this->getColumnRule($alias);
+
+        return $columnRule ? $columnRule->column : $alias;
+    }
+
     public function getRule($key): ?Rule
     {
         if ($rule = $this->getKeywordRule($key)) {

src/Visitors/BuildKeywordsVisitor.php

@@ -83,14 +83,17 @@ protected function buildOrderBy($values)
         Collection::wrap($values)->each(function ($value) {
             $desc = Str::startsWith($value, '-') ? 'desc' : 'asc';
             $column = Str::startsWith($value, '-') ? Str::after($value, '-') : $value;
+            $column = $this->manager->getColumnNameFromAlias($column);
             $qualifiedColumn = SearchStringManager::qualifyColumn($this->builder, $column);
             $this->builder->orderBy($qualifiedColumn, $desc);
         });
     }
 
     protected function buildSelect($values, bool $negated)
     {
-        $columns = Arr::wrap($values);
+        $columns = Collection::wrap($values)->map(function ($value) {
+            return $this->manager->getColumnNameFromAlias($value);
+        });
 
         $columns = $negated
             ? $this->manager->getColumns()->diff($columns)

tests/VisitorBuildKeywordsTest.php

@@ -60,6 +60,15 @@ public function it_uses_only_the_last_select_that_matches()
         $this->assertEquals(['products.description'], $builder->getQuery()->columns);
     }
 
+    /** @test */
+    public function it_uses_the_alias_of_select_columns()
+    {
+        $model = $this->getModelWithColumns(['created_at' => 'date']);
+        $builder = $this->getBuilder('fields:date', $model);
+
+        $this->assertEquals(['models.created_at'], $builder->getQuery()->columns);
+    }
+
     /*
      * OrderBy
      */
@@ -106,6 +115,17 @@ public function it_uses_only_the_last_order_by_that_matches()
         ], $builder->getQuery()->orders);
     }
 
+    /** @test */
+    public function it_uses_the_alias_of_order_by_columns()
+    {
+        $model = $this->getModelWithColumns(['created_at' => 'date']);
+        $builder = $this->getBuilder('sort:date', $model);
+
+        $this->assertEquals([
+            [ 'column' => 'models.created_at', 'direction' => 'asc' ],
+        ], $builder->getQuery()->orders);
+    }
+
     /*
      * Limit
      */