#1760 #1759 - ENH: Add ForTests.rollbackAll(closure) and ForTests.createRollbackAll()

src/main/java/io/ebean/ForTests.java

@@ -0,0 +1,113 @@
+package io.ebean;
+
+import io.ebeaninternal.api.HelpScopeTrans;
+
+/**
+ * Helper methods for testing.
+ */
+public class ForTests {
+
+  /**
+   * Enable or disable <code>@Transactional</code> methods.
+   * <p>
+   * This is intended for testing purposes such that tests
+   * on code with {@code @Transactional} methods don't actually
+   * start or complete transactions.
+   * </p>
+   *
+   * @param enable Set false to disable {@code @Transactional} methods
+   */
+  public static void enableTransactional(boolean enable) {
+    HelpScopeTrans.setEnabled(enable);
+  }
+
+  /**
+   * Run the closure with <code>@Transactional</code> methods
+   * effectively disabled (they won't create/commit transactions).
+   */
+  public static void noTransactional(Runnable run) {
+    try {
+      enableTransactional(false);
+      run.run();
+    } finally {
+      enableTransactional(true);
+    }
+  }
+
+  /**
+   * All transactions started in the closure are effectively rolled back.
+   * <p>
+   * This creates a wrapping transaction that uses {@link Transaction#setNestedUseSavepoint()}.
+   * All nested transactions are created as savepoints. On completion the wrapping
+   * transaction is rolled back.
+   * </p>
+   *
+   * @param run Closure that runs such that all the transactions are rolled back.
+   */
+  public static void rollbackAll(Runnable run) {
+
+    try (Transaction transaction = DB.beginTransaction()) {
+      transaction.setNestedUseSavepoint();
+      run.run();
+
+      transaction.rollback();
+    }
+  }
+
+  /**
+   * Create and return a RollbackAll which should be closed at the end of the test(s).
+   * <p>
+   * In tests for <code>@Before</code> we create the rollbackAll and on
+   * <code>@After</code> we <code>close()</code> it effectively rolling
+   * back all changes made during test execution.
+   * </p>
+   *
+   * <pre>{@code
+   *
+   *   private ForTests.RollbackAll rollbackAll;
+   *
+   *   @Before
+   *   public void before() {
+   *     rollbackAll = ForTests.createRollbackAll();
+   *   }
+   *
+   *   @After
+   *   public void after() {
+   *     rollbackAll.close();
+   *   }
+   *
+   *   ... tests execute and everything is rolled back
+   *
+   *
+   * }</pre>
+   */
+  public static RollbackAll createRollbackAll() {
+
+    final Transaction transaction = DB.beginTransaction();
+    transaction.setNestedUseSavepoint();
+    return new RollbackAll(transaction);
+  }
+
+  /**
+   * A wrapping transaction used in test code to rollback all changes.
+   * <p>
+   * We must ensure that <code>close()</code> is called.
+   * </p>
+   */
+  public static class RollbackAll implements AutoCloseable {
+
+    private final Transaction transaction;
+
+    private RollbackAll(Transaction transaction) {
+      this.transaction = transaction;
+    }
+
+    /**
+     * Rollback the wrapping transaction.
+     */
+    @Override
+    public void close() {
+      transaction.rollback();
+    }
+  }
+}