[5.2] Add "Generated Columns" support to MySQL schema grammar

src/Illuminate/Database/Schema/Grammars/MySqlGrammar.php

@@ -13,7 +13,7 @@ class MySqlGrammar extends Grammar
      *
      * @var array
      */
-    protected $modifiers = ['Unsigned', 'Charset', 'Collate', 'Nullable', 'Default', 'Increment', 'Comment', 'After', 'First'];
+    protected $modifiers = ['VirtualAs', 'StoredAs', 'Unsigned', 'Charset', 'Collate', 'Nullable', 'Default', 'Increment', 'Comment', 'After', 'First'];
 
     /**
      * The possible column serials.
@@ -624,6 +624,34 @@ protected function typeMacAddress(Fluent $column)
         return 'varchar(17)';
     }
 
+    /**
+     * Get the SQL for a generated virtual column modifier.
+     *
+     * @param  \Illuminate\Database\Schema\Blueprint  $blueprint
+     * @param  \Illuminate\Support\Fluent  $column
+     * @return string|null
+     */
+    protected function modifyVirtualAs(Blueprint $blueprint, Fluent $column)
+    {
+        if (! is_null($column->virtualAs)) {
+            return " as ({$column->virtualAs})";
+        }
+    }
+
+    /**
+     * Get the SQL for a generated stored column modifier.
+     *
+     * @param  \Illuminate\Database\Schema\Blueprint  $blueprint
+     * @param  \Illuminate\Support\Fluent  $column
+     * @return string|null
+     */
+    protected function modifyStoredAs(Blueprint $blueprint, Fluent $column)
+    {
+        if (! is_null($column->storedAs)) {
+            return " as ({$column->storedAs}) stored";
+        }
+    }
+
     /**
      * Get the SQL for an unsigned column modifier.
      *

tests/Database/DatabaseMySqlSchemaGrammarTest.php

@@ -328,6 +328,18 @@ public function testAddingColumnAfterAnotherColumn()
         $this->assertEquals('alter table `users` add `name` varchar(255) not null after `foo`', $statements[0]);
     }
 
+    public function testAddingGeneratedColumn()
+    {
+        $blueprint = new Blueprint('products');
+        $blueprint->integer('price');
+        $blueprint->integer('discounted_virtual')->virtualAs('price - 5');
+        $blueprint->integer('discounted_stored')->storedAs('price - 5');
+        $statements = $blueprint->toSql($this->getConnection(), $this->getGrammar());
+
+        $this->assertEquals(1, count($statements));
+        $this->assertEquals('alter table `products` add `price` int not null, add `discounted_virtual` int as (price - 5) not null, add `discounted_stored` int as (price - 5) stored not null', $statements[0]);
+    }
+
     public function testAddingString()
     {
         $blueprint = new Blueprint('users');