Merge pull request #952 from goetas/default-down-migration

Make the down() migration optional

UPGRADE.md

@@ -205,6 +205,7 @@ Here is a list of the most important changes:
          use `Doctrine\Migrations\DependencyFactory` instead
  - Namespace `Doctrine\Migrations\AbstractMigration`       
      - CHANGED: The method `Doctrine\Migrations\AbstractMigration#__construct()` changed signature into `(Doctrine\DBAL\Connection $conn, PSR\Log\LoggerInterface $logger)`
+     - CHANGED: The method `Doctrine\Migrations\AbstractMigration#down()` is not abstract anymore, the default implementation will abort the migration process
      - REMOVED: Property `Doctrine\Migrations\AbstractMigration#$version` was removed 
  - Namespace `Doctrine\Migrations\Provider`
      - REMOVED: Class `Doctrine\Migrations\Provider\SchemaProviderInterface` has been deleted

lib/Doctrine/Migrations/AbstractMigration.php

@@ -15,6 +15,7 @@
 use Doctrine\Migrations\Exception\SkipMigration;
 use Doctrine\Migrations\Query\Query;
 use Psr\Log\LoggerInterface;
+use function sprintf;
 
 /**
  * The AbstractMigration class is for end users to extend from when creating migrations. Extend this class
@@ -129,7 +130,10 @@ abstract public function up(Schema $schema) : void;
     /**
      * @throws MigrationException|DBALException
      */
-    abstract public function down(Schema $schema) : void;
+    public function down(Schema $schema) : void
+    {
+        $this->abortIf(true, sprintf('No down() migration implemented for "%s"', static::class));
+    }
 
     /**
      * @param mixed[] $params

tests/Doctrine/Migrations/Tests/AbstractMigrationTest.php

@@ -4,11 +4,13 @@
 
 namespace Doctrine\Migrations\Tests;
 
+use Doctrine\DBAL\Schema\Schema;
 use Doctrine\Migrations\Exception\AbortMigration;
 use Doctrine\Migrations\Exception\IrreversibleMigration;
 use Doctrine\Migrations\Exception\SkipMigration;
 use Doctrine\Migrations\Query\Query;
 use Doctrine\Migrations\Tests\Stub\AbstractMigrationStub;
+use Doctrine\Migrations\Tests\Stub\AbstractMigrationWithoutDownStub;
 
 class AbstractMigrationTest extends MigrationTestCase
 {
@@ -25,6 +27,16 @@ protected function setUp() : void
         $this->migration = new AbstractMigrationStub($this->getSqliteConnection(), $this->logger);
     }
 
+    public function testDownMigrationIsOptional() : void
+    {
+        $this->expectException(AbortMigration::class);
+        $this->expectExceptionMessage('No down() migration implemented for "Doctrine\Migrations\Tests\Stub\AbstractMigrationWithoutDownStub"');
+
+        $migration = new AbstractMigrationWithoutDownStub($this->getSqliteConnection(), $this->logger);
+        $schema    = $this->createStub(Schema::class);
+        $migration->down($schema);
+    }
+
     public function testGetDescriptionReturnsEmptyString() : void
     {
         self::assertSame('', $this->migration->getDescription());

tests/Doctrine/Migrations/Tests/Stub/AbstractMigrationWithoutDownStub.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\Migrations\Tests\Stub;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+class AbstractMigrationWithoutDownStub extends AbstractMigration
+{
+    public function up(Schema $schema) : void
+    {
+    }
+}