diff -u b/core/modules/migrate/src/Plugin/migrate/source/SqlBase.php b/core/modules/migrate/src/Plugin/migrate/source/SqlBase.php
--- b/core/modules/migrate/src/Plugin/migrate/source/SqlBase.php
+++ b/core/modules/migrate/src/Plugin/migrate/source/SqlBase.php
@@ -60,7 +60,7 @@
       $plugin_id,
       $plugin_definition,
       $migration,
-      \Drupal::state()
+      $container->get('state')
     );
   }
 
@@ -98,24 +98,29 @@
    * Get a connection to the referenced database, adding the connection if
    * necessary.
    *
-   * @param $database_info
+   * @param array $database_info
+   *   Configuration for the source database connection. The keys are:
+   *    'key' - The database connection key.
+   *    'target' - The database connection target.
+   *    'database' - Database configuration array as accepted by
+   *      Database::addConnectionInfo.
    *
    * @return \Drupal\Core\Database\Connection
    *   The connection to use for this plugin's queries.
    */
-  protected function setUpDatabase($database_info) {
-    if (isset($database_info['target'])) {
-      $target = $database_info['target'];
-    }
-    else {
-      $target = 'default';
-    }
+  protected function setUpDatabase(array $database_info) {
     if (isset($database_info['key'])) {
       $key = $database_info['key'];
     }
     else {
       $key = 'migrate';
     }
+    if (isset($database_info['target'])) {
+      $target = $database_info['target'];
+    }
+    else {
+      $target = 'default';
+    }
     if (isset($database_info['database'])) {
       Database::addConnectionInfo($key, $target, $database_info['database']);
     }
diff -u b/core/modules/migrate/src/Tests/SqlBaseTest.php b/core/modules/migrate/src/Tests/SqlBaseTest.php
--- b/core/modules/migrate/src/Tests/SqlBaseTest.php
+++ b/core/modules/migrate/src/Tests/SqlBaseTest.php
@@ -24,6 +24,7 @@
     $sql_base = new TestSqlBase();
 
     // Check the default values.
+    $sql_base->setConfiguration([]);
     $this->assertIdentical($sql_base->getDatabase()->getTarget(), 'default');
     $this->assertIdentical($sql_base->getDatabase()->getKey(), 'migrate');
 
diff -u b/core/modules/migrate_drupal/src/Plugin/migrate/source/DrupalSqlBase.php b/core/modules/migrate_drupal/src/Plugin/migrate/source/DrupalSqlBase.php
--- b/core/modules/migrate_drupal/src/Plugin/migrate/source/DrupalSqlBase.php
+++ b/core/modules/migrate_drupal/src/Plugin/migrate/source/DrupalSqlBase.php
@@ -90,7 +90,7 @@
       $plugin_id,
       $plugin_definition,
       $migration,
-      \Drupal::state(),
+      $container->get('state'),
       $container->get('entity.manager')
     );
   }
diff -u b/core/modules/migrate_drupal/tests/src/Unit/source/d6/Drupal6SqlBaseTest.php b/core/modules/migrate_drupal/tests/src/Unit/source/d6/Drupal6SqlBaseTest.php
--- b/core/modules/migrate_drupal/tests/src/Unit/source/d6/Drupal6SqlBaseTest.php
+++ b/core/modules/migrate_drupal/tests/src/Unit/source/d6/Drupal6SqlBaseTest.php
@@ -68,8 +68,10 @@
    */
   protected function setUp() {
     $plugin = 'placeholder_id';
-    $state = $this->getmock('Drupal\Core\State\StateInterface');
-    $entity_manager = $this->getmock('Drupal\Core\Entity\EntityManagerInterface');
+    /** @var \Drupal\Core\State\StateInterface $state */
+    $state = $this->getMock('Drupal\Core\State\StateInterface');
+    /** @var \Drupal\Core\Entity\EntityManagerInterface $entity_manager */
+    $entity_manager = $this->getMock('Drupal\Core\Entity\EntityManagerInterface');
     $this->base = new TestDrupal6SqlBase($this->migrationConfiguration, $plugin, array(), $this->getMigration(), $state, $entity_manager);
     $this->base->setDatabase($this->getDatabase($this->databaseContents));
   }