diff --git a/core/modules/migrate/tests/src/Kernel/MigrateSourceTestBase.php b/core/modules/migrate/tests/src/Kernel/MigrateSourceTestBase.php
new file mode 100644
index 0000000..54c9135
--- /dev/null
+++ b/core/modules/migrate/tests/src/Kernel/MigrateSourceTestBase.php
@@ -0,0 +1,177 @@
+<?php
+
+namespace Drupal\Tests\migrate\Kernel;
+
+use Drupal\KernelTests\KernelTestBase;
+use Drupal\migrate\Plugin\MigrateIdMapInterface;
+use Drupal\migrate\Plugin\MigrationInterface;
+use Drupal\migrate\Row;
+
+/**
+ * Base class for unit tests of Migrate source plugins.
+ */
+abstract class MigrateSourceTestBase extends KernelTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['migrate'];
+
+  /**
+   * The mocked migration.
+   *
+   * @var MigrationInterface|\Prophecy\Prophecy\ObjectProphecy
+   */
+  protected $migration;
+
+  /**
+   * The source plugin under test.
+   *
+   * @var \Drupal\migrate\Plugin\MigrateSourceInterface
+   */
+  protected $plugin;
+
+  /**
+   * The data provider.
+   *
+   * @see testSource for the elements that should be included in each data set
+   * returned by this method.
+   *
+   * @return array
+   */
+  abstract public function providerSource();
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    /** @var MigrationInterface|\Prophecy\Prophecy\ObjectProphecy $migration */
+    $this->migration = $this->prophesize(MigrationInterface::class);
+
+    $this->migration->id()->willReturn(
+      $this->randomMachineName(16)
+    );
+    // Prophesize a useless ID map plugin, an empty high water property, and
+    // an empty set of destination IDs. Calling code can override these
+    // prophecies later and set up different behaviors.
+    $this->migration->getIdMap()->willReturn(
+      $this->prophesize(MigrateIdMapInterface::class)->reveal()
+    );
+    $this->migration->getHighWaterProperty()->willReturn([]);
+    $this->migration->getDestinationIds()->willReturn([]);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function tearDown() {
+    parent::tearDown();
+    $this->plugin = NULL;
+  }
+
+  /**
+   * Determines the plugin to be tested by reading the class @covers annotation.
+   *
+   * @return string
+   */
+  protected function getPluginClass() {
+    $annotations = $this->getAnnotations();
+
+    if (isset($annotations['class']['covers'])) {
+      return $annotations['class']['covers'][0];
+    }
+    else {
+      $this->fail('No plugin class was specified.');
+    }
+  }
+
+  /**
+   * Instantiates the source plugin under test.
+   *
+   * @param array $configuration
+   *   The plugin configuration.
+   *
+   * @return \Drupal\migrate\Plugin\MigrateSourceInterface|object
+   *   The fully configured source plugin.
+   */
+  protected function getPlugin(array $configuration) {
+    // Only create the plugin once per test.
+    if ($this->plugin) {
+      return $this->plugin;
+    }
+
+    $class = ltrim($this->getPluginClass(), '\\');
+
+    /** @var \Drupal\migrate\Plugin\MigratePluginManager $plugin_manager */
+    $plugin_manager = $this->container->get('plugin.manager.migrate.source');
+
+    foreach ($plugin_manager->getDefinitions() as $id => $definition) {
+      if (ltrim($definition['class'], '\\') == $class) {
+        $this->plugin = $plugin_manager
+          ->createInstance($id, $configuration, $this->migration->reveal());
+
+        $this->migration
+          ->getSourcePlugin()
+          ->willReturn($this->plugin);
+
+        return $this->plugin;
+      }
+    }
+    $this->fail('No plugin found for class ' . $class);
+  }
+
+  /**
+   * Tests the source plugin against a particular data set.
+   *
+   * @param array $source_data
+   *   The source data that the plugin will read.
+   * @param array $expected_data
+   *   The result rows the plugin is expected to return.
+   * @param int $expected_count
+   *   (optional) How many rows the source plugin is expected to return.
+   * @param array $configuration
+   *   (optional) Configuration for the source plugin.
+   */
+  public function testSource(array $source_data, array $expected_data, $expected_count = NULL, array $configuration = []) {
+    $plugin = $this->getPlugin($configuration);
+
+    // All source plugins must define IDs.
+    $this->assertNotEmpty($plugin->getIds());
+
+    // If an expected count was given, assert it only if the plugin is
+    // countable.
+    if (is_numeric($expected_count)) {
+      if ($plugin instanceof \Countable) {
+        $this->assertCount($expected_count, $plugin);
+      }
+      else {
+        $this->fail('Plugin is not countable.');
+      }
+    }
+
+    $i = 0;
+    /** @var Row $row */
+    foreach ($plugin as $row) {
+      $this->assertInstanceOf(Row::class, $row);
+
+      $expected = $expected_data[$i++];
+      $actual = $row->getSource();
+
+      foreach ($expected as $key => $value) {
+        $this->assertArrayHasKey($key, $actual);
+
+        if (is_array($value)) {
+          ksort($value);
+          ksort($actual[$key]);
+          $this->assertEquals($value, $actual[$key]);
+        }
+        else {
+          $this->assertSame((string) $value, (string) $actual[$key]);
+        }
+      }
+    }
+  }
+
+}
diff --git a/core/modules/migrate/tests/src/Kernel/MigrateSqlSourceTestBase.php b/core/modules/migrate/tests/src/Kernel/MigrateSqlSourceTestBase.php
new file mode 100644
index 0000000..08be8c1
--- /dev/null
+++ b/core/modules/migrate/tests/src/Kernel/MigrateSqlSourceTestBase.php
@@ -0,0 +1,83 @@
+<?php
+
+namespace Drupal\Tests\migrate\Kernel;
+
+use Drupal\Core\Database\Driver\sqlite\Connection;
+
+abstract class MigrateSqlSourceTestBase extends MigrateSourceTestBase {
+
+  /**
+   * Builds an in-memory SQLite database from a set of source data.
+   *
+   * @param array $source_data
+   *   The source data, keyed by table name. Each table is an array containing
+   *   the rows in that table.
+   *
+   * @return \Drupal\Core\Database\Driver\sqlite\Connection
+   *   The SQLite database connection.
+   */
+  protected function getDatabase(array $source_data) {
+    if (extension_loaded('pdo_sqlite') == FALSE) {
+      $this->markTestSkipped('The pdo_sqlite extension is unavailable.');
+    }
+
+    // Create an in-memory SQLite database. Plugins can interact with it like
+    // any other database, and it will cease to exist when the connection is
+    // closed.
+    $connection_options = ['database' => ':memory:'];
+    $pdo = Connection::open($connection_options);
+    $connection = new Connection($pdo, $connection_options);
+
+    // Create the tables and fill them with data.
+    foreach ($source_data as $table => $rows) {
+      // Use the biggest row to build the table schema.
+      $counts = array_map('count', $rows);
+      asort($counts);
+      end($counts);
+      $pilot = $rows[key($counts)];
+
+      $connection->schema()
+        ->createTable($table, [
+          // SQLite uses loose affinity typing, so it's OK for every field to
+          // be a text field.
+          'fields' => array_map(function() { return ['type' => 'text']; }, $pilot),
+        ]);
+
+      $fields = array_keys($pilot);
+      $insert = $connection->insert($table)->fields($fields);
+      array_walk($rows, [$insert, 'values']);
+      $insert->execute();
+    }
+
+    return $connection;
+  }
+
+  /**
+   * Tests the source plugin against a particular data set.
+   *
+   * @param array $source_data
+   *   The source data that the plugin will read. See getDatabase() for the
+   *   expected format.
+   * @param array $expected_data
+   *   The result rows the plugin is expected to return.
+   * @param int $expected_count
+   *   (optional) How many rows the source plugin is expected to return.
+   * @param array $configuration
+   *   (optional) Configuration for the source plugin.
+   *
+   * @dataProvider providerSource
+   */
+  public function testSource(array $source_data, array $expected_data, $expected_count = NULL, array $configuration = []) {
+    $plugin = $this->getPlugin($configuration);
+
+    // Since we don't yet inject the database connection, we need to use a
+    // reflection hack to set it in the plugin instance.
+    $reflector = new \ReflectionObject($plugin);
+    $property = $reflector->getProperty('database');
+    $property->setAccessible(TRUE);
+    $property->setValue($plugin, $this->getDatabase($source_data));
+
+    parent::testSource($source_data, $expected_data, $expected_count, $configuration);
+  }
+
+}
diff --git a/core/modules/user/tests/src/Kernel/Plugin/migrate/source/d7/RoleTest.php b/core/modules/user/tests/src/Kernel/Plugin/migrate/source/d7/RoleTest.php
new file mode 100644
index 0000000..88ce0bf
--- /dev/null
+++ b/core/modules/user/tests/src/Kernel/Plugin/migrate/source/d7/RoleTest.php
@@ -0,0 +1,72 @@
+<?php
+
+namespace Drupal\Tests\user\Kernel\Plugin\migrate\source\d7;
+
+use Drupal\Tests\migrate\Kernel\MigrateSqlSourceTestBase;
+
+/**
+ * Tests the d7_user_role source plugin.
+ *
+ * @covers \Drupal\user\Plugin\migrate\source\d7\Role
+ * @group user
+ */
+class RoleTest extends MigrateSqlSourceTestBase  {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['user'];
+
+  /**
+   * {@inheritdoc}
+   */
+  public function providerSource() {
+    $expected = [
+      [
+        'rid' => 1,
+        'name' => 'anonymous user',
+        'permissions' => [
+          'access content',
+        ],
+      ],
+      [
+        'rid' => 2,
+        'name' => 'authenticated user',
+        'permissions' => [
+          'access comments',
+          'access content',
+          'post comments',
+          'post comments without approval',
+        ],
+      ],
+      [
+        'rid' => 3,
+        'name' => 'administrator',
+        'permissions' => [
+          'access comments',
+          'administer comments',
+          'post comments',
+          'post comments without approval',
+          'access content',
+          'administer content types',
+          'administer nodes',
+        ],
+      ],
+    ];
+    $data = [
+      [[], $expected],
+    ];
+    foreach ($expected as $row) {
+      foreach ($row['permissions'] as $permission) {
+        $data[0][0]['role_permission'][] = [
+          'permission' => $permission,
+          'rid' => $row['rid'],
+        ];
+      }
+      unset($row['permissions']);
+      $data[0][0]['role'][] = $row;
+    }
+    return $data;
+  }
+
+}