StatusValue: Allow passing arbitrary data to augment result

This allows extensions and hooks to pass around additional data
about the operation result arbitrarily to supplement value and errors.

When two StatusValue instances are to be merged, it's responsibility
of the caller to ensure either only one has this extra data or none,
but never both (since the type is unrestricted). If necessary, the
caller should merge them before invoking StatusValue::merge.

Bug: T326479
Change-Id: Ibe3f1f8b81bcfcb18551d3ca4cda464e4bdbcbce

RELEASE-NOTES-1.42

@@ -107,6 +107,9 @@ because of Phabricator reports.
   in the future without further notice.
 * MediaWikiIntegrationTestCase::$tablesUsed has been deprecated. The framework
   now detects these automatically.
+* Support for setting dynamic property on StatusValue object has been removed.
+  To pass your arbitrary data along the object, use StatusValue::statusData
+  property (which is always declared).
 * …
 
 === Deprecations in 1.42 ===

includes/Status/Status.php

@@ -83,6 +83,7 @@ class Status extends StatusValue {
 		$result->successCount =& $sv->successCount;
 		$result->failCount =& $sv->failCount;
 		$result->success =& $sv->success;
+		$result->statusData =& $sv->statusData;
 
 		return $result;
 	}
@@ -116,9 +117,6 @@ class Status extends StatusValue {
 	public function __set( $name, $value ) {
 		if ( $name === 'ok' ) {
 			$this->setOK( $value );
-		} elseif ( !property_exists( $this, $name ) ) {
-			// Caller is using undeclared ad-hoc properties
-			$this->$name = $value;
 		} else {
 			throw new RuntimeException( "Cannot set '$name' property." );
 		}

includes/api/ApiEditPage.php

@@ -539,8 +539,8 @@ class ApiEditPage extends ApiBase {
 		switch ( $statusValue ) {
 			case EditPage::AS_HOOK_ERROR:
 			case EditPage::AS_HOOK_ERROR_EXPECTED:
-				if ( isset( $status->apiHookResult ) ) {
-					$r = $status->apiHookResult;
+				if ( $status->statusData !== null ) {
+					$r = $status->statusData;
 					$r['result'] = 'Failure';
 					$apiResult->addValue( null, $this->getModuleName(), $r );
 					return;

includes/libs/StatusValue.php

@@ -63,6 +63,9 @@ class StatusValue {
 	/** @var int Counter for batch operations */
 	public $failCount = 0;
 
+	/** @var mixed arbitrary extra data about the operation */
+	public $statusData;
+
 	/**
 	 * Factory function for fatal errors
 	 *
@@ -285,6 +288,12 @@ class StatusValue {
 	 * @return $this
 	 */
 	public function merge( $other, $overwriteValue = false ) {
+		if ( $this->statusData !== null && $other->statusData !== null ) {
+			throw new RuntimeException( "Status cannot be merged, because they both have \$statusData" );
+		} else {
+			$this->statusData ??= $other->statusData;
+		}
+
 		foreach ( $other->errors as $error ) {
 			$this->addError( $error );
 		}
@@ -294,6 +303,7 @@ class StatusValue {
 		}
 		$this->successCount += $other->successCount;
 		$this->failCount += $other->failCount;
+
 		return $this;
 	}
 

tests/phpunit/includes/api/ApiEditPageTest.php

@@ -1558,7 +1558,7 @@ class ApiEditPageTest extends ApiTestCase {
 
 		$this->setTemporaryHook( 'EditFilterMergedContent',
 			static function ( $unused1, $unused2, Status $status ) {
-				$status->apiHookResult = [ 'msg' => 'A message for you!' ];
+				$status->statusData = [ 'msg' => 'A message for you!' ];
 				return false;
 			} );