[DBAL-255] Fix dropping columns with default contraints in SQLSrv

lib/Doctrine/DBAL/Schema/SQLServerSchemaManager.php

@@ -213,4 +213,35 @@ class SQLServerSchemaManager extends AbstractSchemaManager
 
         return $this->_getPortableTableIndexesList($tableIndexes, $table);
     }
+
+    /**
+     * @override
+     */
+    public function alterTable(TableDiff $tableDiff)
+    {
+        if(count($tableDiff->removedColumns) > 0) {
+            foreach($tableDiff->removedColumns as $col){
+                $columnConstraintSql = $this->getColumnConstraintSQL($tableDiff->name, $col->getName());
+                foreach ($this->_conn->fetchAll($columnConstraintSql) as $constraint) {
+                    $this->_conn->exec("ALTER TABLE $tableDiff->name DROP CONSTRAINT " . $constraint['Name']);
+                }
+            }
+        }
+
+        return parent::alterTable($tableDiff);
+    }
+
+    /**
+     * This function retrieves the constraints for a given column.
+     */
+    private function getColumnConstraintSQL($table, $column)
+    {
+        return "SELECT SysObjects.[Name]
+            FROM SysObjects INNER JOIN (SELECT [Name],[ID] FROM SysObjects WHERE XType = 'U') AS Tab
+            ON Tab.[ID] = Sysobjects.[Parent_Obj]
+            INNER JOIN sys.default_constraints DefCons ON DefCons.[object_id] = Sysobjects.[ID]
+            INNER JOIN SysColumns Col ON Col.[ColID] = DefCons.[parent_column_id] AND Col.[ID] = Tab.[ID]
+            WHERE Col.[Name] = " . $this->_conn->quote($column) ." AND Tab.[Name] = " . $this->_conn->quote($table) . "
+            ORDER BY Col.[Name]";
+    }
 }

doctrine-common @ 17e77400

-Subproject commit 14eb4d62b6e0a87cd99200078c38644bbd216e42
+Subproject commit 17e774007b98beb2e253e645260e0f9c32f4c936

tests/Doctrine/Tests/DBAL/Functional/Schema/SQLServerSchemaManagerTest.php

@@ -2,7 +2,11 @@
 
 namespace Doctrine\Tests\DBAL\Functional\Schema;
 
-use Doctrine\DBAL\Schema;
+use Doctrine\DBAL\Schema\Table;
+use Doctrine\DBAL\Schema\TableDiff;
+use Doctrine\DBAL\Schema\ColumnDiff;
+use Doctrine\DBAL\Schema\Column;
+use Doctrine\DBAL\Types\Type;
 
 class SQLServerSchemaManagerTest extends SchemaManagerFunctionalTestCase
 {
@@ -10,4 +14,24 @@ class SQLServerSchemaManagerTest extends SchemaManagerFunctionalTestCase
 	{
 		return "mssql";
 	}
+
+    /**
+     * @group DBAL-255
+     */
+    public function testDropColumnConstraints()
+    {
+        $table = new Table('sqlsrv_drop_column');
+        $table->addColumn('id', 'integer');
+        $table->addColumn('todrop', 'decimal', array('default' => 10.2));
+
+        $this->_sm->createTable($table);
+
+        $diff = new TableDiff('sqlsrv_drop_column', array(), array(), array(
+            new Column('todrop', Type::getType('decimal'))
+        ));
+        $this->_sm->alterTable($diff);
+
+        $columns = $this->_sm->listTableColumns('sqlsrv_drop_column');
+        $this->assertEquals(1, count($columns));
+    }
 }