Issue #3130973 by daffie, plach, Charlie ChX Negyesi: Make the backend...

Issue #3130973 by daffie, plach, Charlie ChX Negyesi: Make the backend overridable service discovery also check the database type for an overridden service

core/lib/Drupal/Core/DependencyInjection/Compiler/BackendCompilerPass.php

@@ -37,6 +37,7 @@ class BackendCompilerPass implements CompilerPassInterface {
    * {@inheritdoc}
    */
   public function process(ContainerBuilder $container) {
+    $driver_backend = NULL;
     if ($container->hasParameter('default_backend')) {
       $default_backend = $container->getParameter('default_backend');
       // Opt out from the default backend.
@@ -46,7 +47,8 @@ public function process(ContainerBuilder $container) {
     }
     else {
       try {
-        $default_backend = $container->get('database')->driver();
+        $driver_backend = $container->get('database')->driver();
+        $default_backend = $container->get('database')->databaseType();
         $container->set('database', NULL);
       }
       catch (\Exception $e) {
@@ -62,7 +64,10 @@ public function process(ContainerBuilder $container) {
       if ($container->hasAlias($id)) {
         continue;
       }
-      if ($container->hasDefinition("$default_backend.$id") || $container->hasAlias("$default_backend.$id")) {
+      if ($container->hasDefinition("$driver_backend.$id") || $container->hasAlias("$driver_backend.$id")) {
+        $container->setAlias($id, new Alias("$driver_backend.$id"));
+      }
+      elseif ($container->hasDefinition("$default_backend.$id") || $container->hasAlias("$default_backend.$id")) {
         $container->setAlias($id, new Alias("$default_backend.$id"));
       }
     }

core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/BackendCompilerPassTest.php

@@ -87,6 +87,25 @@ public function providerTestProcess() {
     $container->setParameter('default_backend', '');
     $data[] = [$prefix . 'Default', $container];
 
+    // Set the mysql and the DrivertestMysql service, now the DrivertestMysql
+    // service, as it is the driver override, should be used.
+    $container = $this->getDrivertestMysqlContainer($service);
+    $container->setDefinition('mysql.service', new Definition(__NAMESPACE__ . '\\ServiceClassMysql'));
+    $container->setDefinition('DrivertestMysql.service', new Definition(__NAMESPACE__ . '\\ServiceClassDrivertestMysql'));
+    $data[] = [$prefix . 'DrivertestMysql', $container];
+
+    // Set the mysql service, now the mysql service, as it is the database_type
+    // override, should be used.
+    $container = $this->getDrivertestMysqlContainer($service);
+    $container->setDefinition('mysql.service', new Definition(__NAMESPACE__ . '\\ServiceClassMysql'));
+    $data[] = [$prefix . 'Mysql', $container];
+
+    // Set the DrivertestMysql service, now the DrivertestMysql service, as it
+    // is the driver override, should be used.
+    $container = $this->getDrivertestMysqlContainer($service);
+    $container->setDefinition('DrivertestMysql.service', new Definition(__NAMESPACE__ . '\\ServiceClassDrivertestMysql'));
+    $data[] = [$prefix . 'DrivertestMysql', $container];
+
     return $data;
   }
 
@@ -126,6 +145,24 @@ protected function getMysqlContainer($service) {
     return $container;
   }
 
+  /**
+   * Creates a container with a DrivertestMysql database mock definition in it.
+   *
+   * This is necessary because the container clone does not clone the parameter
+   * bag so the setParameter() call effects the parent container as well.
+   *
+   * @param $service
+   *
+   * @return \Symfony\Component\DependencyInjection\ContainerBuilder
+   */
+  protected function getDrivertestMysqlContainer($service) {
+    $container = new ContainerBuilder();
+    $container->setDefinition('service', $service);
+    $mock = $this->getMockBuilder('Drupal\driver_test\Driver\Database\DrivertestMysql\Connection')->setMethods(NULL)->disableOriginalConstructor()->getMock();
+    $container->set('database', $mock);
+    return $container;
+  }
+
 }
 
 class ServiceClassDefault {
@@ -139,3 +176,6 @@ class ServiceClassMariaDb extends ServiceClassMysql {
 
 class ServiceClassSqlite extends ServiceClassDefault {
 }
+
+class ServiceClassDrivertestMysql extends ServiceClassDefault {
+}