[ticket/14742] Avoid loop while reverting data

This combines reverted updata_data and revert_data into a single array.

PHPBB3-14742

phpBB/phpbb/db/migration/helper.php

@@ -81,4 +81,36 @@ class helper
 
 		return $steps;
 	}
+
+	/**
+	 * Reverse the update steps from an array of data changes
+	 *
+	 * 'If' statements and custom methods will be skipped, for all
+	 * other calls the reverse method of the tool class will be called
+	 *
+	 * @param array $steps Update changes from migration
+	 *
+	 * @return array
+	 */
+	public function reverse_update_data($steps)
+	{
+		$reversed_array = array();
+
+		foreach ($steps as $step)
+		{
+			$parts = explode('.', $step[0]);
+			$parameters = $step[1];
+
+			$class = $parts[0];
+			$method = isset($parts[1]) ? $parts[1] : false;
+
+			if ($class !== 'if' && $class !== 'custom')
+			{
+				array_unshift($parameters, $method);
+				$reversed_array[] = array($class . '.reverse', $parameters);
+			}
+		}
+
+		return array_reverse($reversed_array);
+	}
 }

phpBB/phpbb/db/migration/tool/config.php

@@ -150,6 +150,11 @@ class config implements \phpbb\db\migration\tool\tool_interface
 					$arguments[0],
 				);
 			break;
+
+			case 'reverse':
+				// It's like double negative
+				$call = array_shift($arguments);
+			break;
 		}
 
 		if ($call)

phpBB/phpbb/db/migration/tool/config_text.php

@@ -115,6 +115,11 @@ class config_text implements \phpbb\db\migration\tool\tool_interface
 					$arguments[] = '';
 				}
 			break;
+
+			case 'reverse':
+				// It's like double negative
+				$call = array_shift($arguments);
+			break;
 		}
 
 		if ($call)

phpBB/phpbb/db/migration/tool/module.php

@@ -454,6 +454,11 @@ class module implements \phpbb\db\migration\tool\tool_interface
 			case 'remove':
 				$call = 'add';
 			break;
+
+			case 'reverse':
+				// It's like double negative
+				$call = array_shift($arguments);
+			break;
 		}
 
 		if ($call)

phpBB/phpbb/db/migration/tool/permission.php

@@ -637,6 +637,11 @@ class permission implements \phpbb\db\migration\tool\tool_interface
 					$arguments[0],
 				);
 			break;
+
+			case 'reverse':
+				// It's like double negative
+				$call = array_shift($arguments);
+			break;
 		}
 
 		if ($call)

phpBB/phpbb/db/migrator.php

@@ -423,19 +423,11 @@ class migrator
 
 		if ($state['migration_data_done'])
 		{
-			if ($state['migration_data_state'] !== 'revert_data')
+			$steps = array_merge($this->helper->reverse_update_data($migration->update_data()), $migration->revert_data());
-			{
+			$result = $this->process_data_step($steps, $state['migration_data_state']);
-				$result = $this->process_data_step($migration->update_data(), $state['migration_data_state'], true);
-
-				$state['migration_data_state'] = ($result === true) ? 'revert_data' : $result;
-			}
-			else
-			{
-				$result = $this->process_data_step($migration->revert_data(), '', false);
 
 			$state['migration_data_state'] = ($result === true) ? '' : $result;
 			$state['migration_data_done'] = ($result === true) ? false : true;
-			}
 
 			$this->set_migration_state($name, $state);
 		}
@@ -596,6 +588,13 @@ class migrator
 					throw new \phpbb\db\migration\exception('MIGRATION_INVALID_DATA_MISSING_STEP', $step);
 				}
 
+				if ($reverse)
+				{
+					// We might get unexpected results when trying
+					// to revert this, so just avoid it
+					return false;
+				}
+
 				$condition = $parameters[0];
 
 				if (!$condition)