2 files changed, 55 insertions, 6 deletions
diff --git a/modules/field/modules/field_sql_storage/field_sql_storage.module b/modules/field/modules/field_sql_storage/field_sql_storage.module
index 695561624..2ed783507 100644
--- a/modules/field/modules/field_sql_storage/field_sql_storage.module
+++ b/modules/field/modules/field_sql_storage/field_sql_storage.module
@@ -236,13 +236,37 @@ function field_sql_storage_field_update_forbid($field, $prior_field, $has_data)
 function field_sql_storage_field_storage_update_field($field, $prior_field, $has_data) {
   if (! $has_data) {
     // There is no data. Re-create the tables completely.
-    $prior_schema = _field_sql_storage_schema($prior_field);
-    foreach ($prior_schema as $name => $table) {
-      db_drop_table($name, $table);
+
+    if (Database::getConnection()->supportsTransactionalDDL()) {
+      // If the database supports transactional DDL, we can go ahead and rely
+      // on it. If not, we will have to rollback manually if something fails.
+      $transaction = db_transaction();
+    }
+
+    try {
+      $prior_schema = _field_sql_storage_schema($prior_field);
+      foreach ($prior_schema as $name => $table) {
+        db_drop_table($name, $table);
+      }
+      $schema = _field_sql_storage_schema($field);
+      foreach ($schema as $name => $table) {
+        db_create_table($name, $table);
+      }
     }
-    $schema = _field_sql_storage_schema($field);
-    foreach ($schema as $name => $table) {
-      db_create_table($name, $table);
+    catch (Exception $e) {
+      if (Database::getConnection()->supportsTransactionalDDL()) {
+        $transaction->rollback();
+      }
+      else {
+        // Recreate tables.
+        $prior_schema = _field_sql_storage_schema($prior_field);
+        foreach ($prior_schema as $name => $table) {
+          if (!db_table_exists($name)) {
+            db_create_table($name, $table);
+          }
+        }
+      }
+      throw $e;
     }
   }
   else {
diff --git a/modules/field/modules/field_sql_storage/field_sql_storage.test b/modules/field/modules/field_sql_storage/field_sql_storage.test
index f94344fa2..773de3d07 100644
--- a/modules/field/modules/field_sql_storage/field_sql_storage.test
+++ b/modules/field/modules/field_sql_storage/field_sql_storage.test
@@ -306,6 +306,31 @@ class FieldSqlStorageTestCase extends DrupalWebTestCase {
   }
 
   /**
+   * Test that failure to create fields is handled gracefully.
+   */
+  function testFieldUpdateFailure() {
+    // Create a text field.
+    $field = array('field_name' => 'test_text', 'type' => 'text', 'settings' => array('max_length' => 255));
+    $field = field_create_field($field);
+
+    // Attempt to update the field in a way that would break the storage.
+    $prior_field = $field;
+    $field['settings']['max_length'] = -1;
+    try {
+      field_update_field($field);
+      $this->fail(t('Update succeeded.'));
+    }
+    catch (Exception $e) {
+      $this->pass(t('Update properly failed.'));
+    }
+
+    // Ensure that the field tables are still there.
+    foreach (_field_sql_storage_schema($prior_field) as $table_name => $table_info) {
+      $this->assertTrue(db_table_exists($table_name), t('Table %table exists.', array('%table' => $table_name)));
+    }
+  }
+
+  /**
    * Test adding and removing indexes while data is present.
    */
   function testFieldUpdateIndexesWithData() {